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Features
* Monolithic Field Programmable System Level Integrated Circuit (FPSLICTM) *
- AT40K SRAM-based FPGA with Embedded High-performance RISC AVR(R) Core, Extensive Data and Instruction SRAM and JTAG ICE 5,000 to 40,000 Gates of Patented SRAM-based AT40K FPGA with FreeRAMTM - 2 - 18.4 Kbits of Distributed Single/Dual Port FPGA User SRAM - High-performance DSP Optimized FPGA Core Cell - Dynamically Reconfigurable In-System - FPGA Configuration Access Available On-chip from AVR Microcontroller Core to Support Cache Logic(R) Designs - Very Low Static and Dynamic Power Consumption - Ideal for Portable and Handheld Applications Patented AVR Enhanced RISC Architecture - 120+ Powerful Instructions - Most Single Clock Cycle Execution - High-performance Hardware Multiplier for DSP-based Systems - Approaching 1 MIPS per MHz Performance - C Code Optimized Architecture with 32 x 8 General-purpose Internal Registers - Low-power Idle, Power-save and Power-down Modes - 100 A Standby and Typical 2-3 mA per MHz Active Up to 36 Kbytes of Dynamically Allocated Instruction and Data SRAM - Up to 16 Kbytes x 16 Internal 15 ns Instructions SRAM - Up to 16 Kbytes x 8 Internal 15 ns Data SRAM JTAG (IEEE std. 1149.1 Compliant) Interface - Extensive On-chip Debug Support - Limited Boundary-scan Capabilities According to the JTAG Standard (AVR Ports) AVR Fixed Peripherals - Industry-standard 2-wire Serial Interface - Two Programmable Serial UARTs - Two 8-bit Timer/Counters with Separate Prescaler and PWM - One 16-bit Timer/Counter with Separate Prescaler, Compare, Capture Modes and Dual 8-, 9- or 10-bit PWM Support for FPGA Custom Peripherals - AVR Peripheral Control - 16 Decoded AVR Address Lines Directly Accessible to FPGA - FPGA Macro Library of Custom Peripherals 16 FPGA Supplied Internal Interrupts to AVR Up to Four External Interrupts to AVR 8 Global FPGA Clocks - Two FPGA Clocks Driven from AVR Logic - FPGA Global Clock Access Available from FPGA Core Multiple Oscillator Circuits - Programmable Watchdog Timer with On-chip Oscillator - Oscillator to AVR Internal Clock Circuit - Software-selectable Clock Frequency - Oscillator to Timer/Counter for Real-time Clock VCC: 3.0V - 3.6V 3.3V 33 MHz PCI-compliant FPGA I/O - 20 mA Sink/Source High-performance I/O Structures - All FPGA I/O Individually Programmable High-performance, Low-power 0.35 CMOS Five-layer Metal Process State-of-the-art Integrated PC-based Software Suite including Co-verification 5V I/O Tolerant
*
* * *
5K - 40K Gates of AT40K FPGA with 8-bit Microcontroller, up to 36K Bytes of SRAM and On-chip JTAG ICE AT94K Series Field Programmable System Level Integrated Circuit
*
* * * *
* * * * *
Rev. 1138F-FPSLI-06/02
1
Description
The AT94K Series FPSLIC family shown in Table 1 is a combination of the popular Atmel AT40K Series SRAM FPGAs and the high-performance Atmel AVR 8-bit RISC microcontroller with standard peripherals. Extensive data and instruction SRAM as well as device control and management logic are included on this monolithic device, fabricated on Atmel's 0.35 fivelayer metal CMOS process. The AT40K FPGA core is a fully 3.3V PCI-compliant, SRAM-based FPGA with distributed 10 ns programmable synchronous/asynchronous, dual-port/single-port SRAM, 8 global clocks, Cache Logic ability (partially or fully reconfigurable without loss of data) and 5,000 to 40,000 usable gates. Table 1. The AT94K Series Characteristics
Device FPGA Gates FPGA Core Cells FPGA SRAM Bits FPGA Registers (Total) Maximum FPGA User I/O AVR Programmable I/O Lines Program SRAM Data SRAM Hardware Multiplier (8-bit) 2-wire Serial Interface UARTs Watchdog Timer Timer/Counters Real-time Clock JTAG ICE Typical AVR throughput Operating Voltage(2) @ 25 MHz @ 40 MHz AT94K05AL/AX 5K 256 2048 436 96 8 4 Kbytes - 16 Kbytes 4 Kbytes - 16 Kbytes Yes Yes 2 Yes 3 Yes Yes
(1)
AT94K10AL/AX 10K 576 4096 846 144 16 20 Kbytes - 32 Kbytes 4 Kbytes- 16 Kbytes Yes Yes 2 Yes 3 Yes Yes
(1)
AT94K40AL/AX 40K 2304 18432 2862 288 16 20 Kbytes - 32 Kbytes 4 Kbytes - 16 Kbytes Yes Yes 2 Yes 3 Yes Yes(1) 19 MIPS 30 MIPS 3.0 - 3.6V(2) 1.6 - 2.0V(2)
19 MIPS 30 MIPS 3.0 - 3.6V
(2)
19 MIPS 30 MIPS 3.0 - 3.6V
(2)
AL AX
1.6 - 2.0V (2)
1.6 - 2.0V(2)
Notes:
1. FPSLIC parts with JTAG ICE support can be identified by the letter "J" after the device date code, e.g., 4201 (no ICE support) and 4201J (with ICE support), see Figure 1. 2. FPSLIC devices should be laid out during PCB design to support a split power supply. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note, available on the Atmel web site at http://www.atmel.com/atmel/acrobat/doc2308.pdf.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 1. FPSLIC Device Date Code with JTAG ICE Support
(R)
AT94K40AL-25DQC
0H1230 4201J
Date Code "J" indicates JTAG ICE support
The AT94K series architecture is shown in Figure 2. Figure 2. AT94K Series Architecture
PROGRAMMABLE I/O
5 - 40K Gates FPGA
Up to 16 Addr Decoder
Up to 16K x 16 Program SRAM Memory
Up to 16 Interrupt Lines
4 Interrupt Lines 2-wire Serial Unit
I/O
I/O with Multiply
Two 8-bit Timer/Counters
JTAG ICE
Up to 16K x 8 Data SRAM
16 Prog. I/O Lines
I/O
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Rev. 1138F-FPSLI-06/02
The embedded AVR core achieves throughputs approaching 1 MIPS per MHz by executing powerful instructions in a single-clock cycle, and allows system designers to optimize power consumption versus processing speed. The AVR core is based on an enhanced RISC architecture that combines a rich instruction set with 32 general-purpose working registers. All 32 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent registers to be accessed in one single instruction executed in one clock cycle. The resulting architecture is more code-efficient while achieving throughputs up to ten times faster than conventional CISC microcontrollers at the same clock frequency. The AVR executes out of onchip SRAM. Both the FPGA configuration SRAM and the AVR instruction code SRAM can be automatically loaded at system power-up using Atmel's in-system programmable (ISP) AT17 Series EEPROM Configuration Memories. State-of-the-art FPSLIC design tools, System Designer TM, were developed in conjunction with the FPSLIC architecture to help reduce overall time-to-market by integrating microcontroller development and debug, FPGA development and Place and Route, and complete system co-verification in one easy-to-use software tool.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
FPGA Core
The AT40K core can be used for high-performance designs, by implementing a variety of compute-intensive arithmetic functions. These include adaptive finite impulse response (FIR) filters, fast Fourier transforms (FFT), convolvers, interpolators, and discrete-cosine transforms (DCT) that are required for video compression and decompression, encryption, convolution and other multimedia applications.
Fast, Flexible and Efficient SRAM
The AT40K core offers a patented distributed 10 ns SRAM capability where the RAM can be used without losing logic resources. Multiple independent, synchronous or asynchronous, dual-port or single-port RAM functions (FIFO, scratch pad, etc.) can be created using Atmel's macro generator tool. The AT40K cores patented 8-sided core cell with direct horizontal, vertical and diagonal cellto-cell connections implements ultra-fast array multipliers without using any busing resources. The AT40K core's Cache Logic capability enables a large number of design coefficients and variables to be implemented in a very small amount of silicon, enabling vast improvement in system speed. The AT40K FPGA core is capable of implementing Cache Logic (dynamic full/partial logic reconfiguration, without loss of data, on-the-fly) for building adaptive logic and systems. As new logic functions are required, they can be loaded into the logic cache without losing the data already there or disrupting the operation of the rest of the chip; replacing or complementing the active logic. The AT40K FPGA core can act as a reconfigurable resource within the FPSLIC environment. The AT40K is capable of implementing user-defined, automatically generated, macros; speed and functionality are unaffected by the macro orientation or density of the target device. This enables the fastest, most predictable and efficient FPGA design approach and minimizes design risk by reusing already proven functions. The Automatic Component Generators work seamlessly with industry-standard schematic and synthesis tools to create fast, efficient designs. The patented AT40K architecture employs a symmetrical grid of small yet powerful cells connected to a flexible busing network. Independently controlled clocks and resets govern every column of four cells. The FPSLIC device is surrounded on three sides by programmable I/Os. Core usable gate counts range from 5,000 to 40,000 gates and 436 to 2,864 registers. Pin locations are consistent throughout the FPSLIC family for easy design migration in the same package footprint. The Atmel AT40K FPGA core architecture was developed to provide the highest levels of performance, functional density and design flexibility. The cells in the FPGA core array are small, efficient and can implement any pair of Boolean functions of (the same) three inputs or any single Boolean function of four inputs. The cell's small size leads to arrays with large numbers of cells. A simple, high-speed busing network provides fast, efficient communication over medium and long distances.
Fast, Efficient Array and Vector Multipliers
Cache Logic Design
Automatic Component Generators
The Symmetrical Array
At the heart of the Atmel FPSLIC architecture is a symmetrical array of identical cells. The array is continuous from one edge to the other, except for bus repeaters spaced every four cells, see Figure 3. At the intersection of each repeater row and column is a 32 x 4 RAM block accessible by adjacent buses. The RAM can be configured as either a single-ported or dualported RAM, with either synchronous or asynchronous operation.
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Rev. 1138F-FPSLI-06/02
The Busing Network
Figure 3. Busing Network
= I/O Pad = AT40K Cell = Repeater Row = Repeater = RAM Block
Interface to AVR
Figure 4 depicts one of five identical FPGA busing planes. Each plane has three bus resources: a local-bus resource (the middle bus) and two express-bus resources. Bus resources are connected via repeaters. Each repeater has connections to two adjacent localbus segments and two express-bus segments. Each local-bus segment spans four cells and connects to consecutive repeaters. Each express-bus segment spans eight cells and bypasses a repeater. Repeaters regenerate signals and can connect any bus to any other bus (all pathways are legal) on the same plane. Although not shown, a local bus can bypass a repeater via a programmable pass gate, allowing long on-chip tri-state buses to be created. Lo ca l/loc al tu r ns ar e im ple me nte d th ro ug h p as s g a tes in the c ell-b us int er fac e. Express/express turns are implemented through separate pass gates distributed throughout the array.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 4. Busing Plane (One of Five)
= AT40K Core Cell
= Local/local or Express/express Turn Point
= Row Repeater
= Column
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Rev. 1138F-FPSLI-06/02
Cell Connections
Figure 5(a) depicts direct connections between an FPGA cell and its eight nearest neighbors. Figure 5(b) shows the connections between a cell five horizontal local buses (one per busing plane) and five vertical local buses (one per busing plane). Figure 5. Cell Connections
CELL
CELL
CELL
Y X X
WXYZL
CELL
Y X
CELL
X Y
Y
CELL
W X Y Z L
CELL
CELL
CELL
CELL
(a) Cell-to-Cell Connections
(b) Cell-to-Bus Connections
The Cell
Figure 6 depicts the AT40K FPGA embedded core logic cell. Configuration bits for separate muxes and pass gates are independent. All permutations of programmable muxes and pass gates are legal. Vn is connected to the vertical local bus in plane n. Hn is connected to the horizontal local bus in plane n. A local/local turn in plane n is achieved by turning on the two pass gates connected to Vn and Hn. Up to five simultaneous local/local turns are possible. The logic cell can be configured in several "modes". The logic cell flexibility makes the FPGA architecture well suited to all digital design application areas, see Figure 7. The IDS layout tool automatically optimizes designs to utilize the cell flexibility.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 6. The Cell
"1" NW NE SE SW "1" "1" N E S W
X
W
Y
Z FB
X
W
Y
8 X 1 LUT
8 X 1 LUT
OUT "0" "1"
OUT "1" V1 H1 V2 H2 V3 H3 V4 H4 V5 H5
10
Z D Q CLOCK RESET/SET "1" OEH OEV L
X
Y
NW NE SE SW
N
E
S
W
X Y W Z FB
= = = = =
Diagonal Direct Connect or Bus Orthogonal Direct Connect or Bus Bus Connection Bus Connection Internal Feedback
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Rev. 1138F-FPSLI-06/02
Figure 7. Some Single Cell Modes
A B C D 4 LUT
Synthesis Mode
DQ
Q (Registered) and/or Q
3 LUT
SUM or DQ SUM (Registered) and/or CARRY
Arithmetic Mode
3 LUT
3 LUT
A B C
DQ
DSP/Multiplier Mode
3 LUT
A B C D
PRODUCT (Registered) or PRODUCT and/or CARRY
3 LUT
DQ
Q and/or
Counter Mode
CARRY IN 3 LUT
CARRY
Tri-State/Mux Mode
A B C EN
2:1 MUX
Q
RAM
There are two types of RAM in the FPSLIC device: the FreeRAM distributed through the FPGA Core and the SRAM shared by the AVR and FPGA. The SRAM is described in "FPGA/AVR Interface and System Control" on page 21. The 32 x 4 dual-ported FPGA FreeRAM blocks are dispersed throughout the array and are connected in each sector as shown in Figure 8. A four-bit Input Data bus connects to four horizontal local buses (Plane 1) distributed over four sector rows. A four-bit Output Data bus connects to four horizontal local buses (Plane 2) distributed over four sector rows. A five-bit Input-address bus connects to five vertical express buses in the same sector column (column 3). A five-bit Output-address bus connects to five vertical express buses in the same column. WAddr (Write Address) and RAddr (Read Address) alternate positions in horizontally aligned RAM blocks. For the left-
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
most RAM blocks, RAddr is on the left and WAddr is on the right. For the right-most RAM blocks, WAddr is on the left and RAddr is tied off. For single-ported RAM, WAddr is the READ/WRITE address port and Din is the (bi-directional) data port. The right-most RAM blocks can be used only for single-ported memories. WE and OE connect to the vertical express buses in the same column on Plane V1 and V2, respectively. WAddr, RAddr, WE and OE connect to express buses that are full length at array edge. Reading and writing the 32 x 4 dual-port RAM are independent of each other. Reading the 32 x 4 dual-port RAM is completely asynchronous. Latches are transparent; when Load is logic 1, data flows through; when Load is logic 0, data is latched. Each bit in the 32 x 4 dual-port RAM is also a transparent latch. The front-end latch and the memory latch together and form an edge-triggered flip-flop. When a bit nibble is (Write) addressed and LOAD is logic 1 and WE is logic 0, DATA flows through the bit. When a nibble is not (Write) addressed or LOAD is logic 0 or WE is logic 1, DATA is latched in the nibble. The two CLOCK muxes are controlled together; they both select CLOCK or they both select "1". CLOCK is obtained from the clock for the sector-column immediately to the left and immediately above the RAM block. Writing any value to the RAM Clear Byte during configuration clears the RAM, see Figure 5 and Figure 6. Figure 8. FPGA RAM Connections (One RAM Block)
Sector Clock Mux
CLK
CLK
CLK
CLK
CLK Din
Dout
WAddr RAddr 32X4 RAM WE OE
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Rev. 1138F-FPSLI-06/02
Figure 9. FreeRAM Logic(1)
CLOCK "1" "1"
READ ADDR
5
Load Read
WRITE ADDR
5
Load Latch
Write
32 x 4 Dual-port RAM "1" OE
WE
Load Latch 4
Write
DATA IN
Load Latch
4 Data Clear Data DATA
RAM-Clear
Note: 1. For dual port, the switches on READ ADDR and DATA OUT would be on. The other two would be off. The reverse is true for single port.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
Rev. 1138F-FPSLI-06/02
Note: 1. These layouts can be generated automatically using the Macro Generators.
WE Write Address
2-to-4 Decoder
Figure 10. FreeRAM Example: 128 x 8 Dual-ported RAM (Asynchronous)(1)
2-to-4 Decoder
Read Address Dout(0) Dout(1) Dout(2) Dout(3)
Din(0) Din(1) Din(2) Din(3)
Din RAddr WE OE Dout WAddr Din Dout Din Dout Din Dout WAddr RAddr WE OE RAddr WAddr WE OE WAddr RAddr WE OE
AT94K Series FPSLIC
Din(4) Din(5) Din(6) Din(7)
Din RAddr WE OE Dout WAddr Din WAddr WE OE Dout RAddr Din Dout Din Dout RAddr WAddr WE OE WAddr RAddr WE OE
Dout(4) Dout(5) Dout(6) Dout(7)
Local Buses Express Buses
Dedicated Connections
13
Clocking and Set/Reset
Six of the eight dedicated Global Clock buses (1, 2, 3, 4, 7 and 8) are connected to a dual-use Global Clock pin. In addition, two Global Clock buses (5 and 6) are driven from clock signals generated within the AVR microcontroller core, see Figure 11. An FPGA core internal signal can be placed on any Global Clock bus by routing that signal to a Global Clock access point in the corners of the embedded core. Each column of the array has a Column Clock selected from one of the eight Global Clock buses. The left edge Column Clock mux has two additional inputs from dual-use pins FCK1, see Figure 8, and FCK2 to provide fast clocking to left-side I/O. Each sector column of four cells can be clocked from a (Plane 4) express bus or from the Column Clock. Clocking to the 4 cells of a sector can be disabled. The Plane 4 express bus used for clocking is half length at the array edge. The clock provided to each sector column of four cells can be either inverted or not inverted. The register in each cell is triggered on a rising clock edge. On power-up, constant "0" is provided to each register's clock pins. A dedicated Global Set/Reset bus, see Figure 9, can be driven by any USER I/O pad, except those used for clocking, Global or Fast. An internal signal can be placed on the Global Set/Reset bus by routing that signal to the pad programmed as the Global Set/Reset input. Global Set/Reset is distributed to each column of the array. Each sector column of four cells can be Set/Reset by a (Plane 5) express bus or by the Global Set/Reset. The Plane 5 express bus used for Set/Reset is half length at array edge. The Set/Reset provided to each sector column of four cells can be either inverted or not inverted. The function of the Set/Reset input of a register (either Set or Reset) is determined by a configuration bit for each cell. The Set/Reset input of a register is Active Low (logic 0). Setting or resetting of a register is asynchronous. On power-up, a logic 1 (High) is provided by each register, i.e., all registers are set at power-up. Figure 11. FPGA Clocks from AVR
TO FPGA CORE GCK5 AVR SYSTEM CLOCK (AVR CLK)
AVR SYSTEM CLOCK (AVR CLK) TO FPGA CORE GCK6 GCK6 TIMER OSC TOSC1 (AS2 SET IN ASSR) WATCHDOG CLOCK "1"
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
The FPGA clocks from the AVR are effected differently in the various sleep modes of the AVR, see Table 2. The source clock into the FPGA GCK5 and GCK6 will determine what happens during the various power-down modes of the AVR. If the XTAL clock input is used as an FPGA clock (GCK5 or GCK6) in Idle mode, it will still be running. In Power-down/save mode the XTAL clock input will be off. If the TOSC clock input is used as an FPGA clock (GCK6) in Idle mode, it will still be running in Power-save mode but will be off in Power-down mode. If the Watchdog Timer is used as an FPGA clock (GCK6) and was enabled in the AVR, it will be running in all sleep modes. Table 2. Clock Activity in Various Modes
Mode Clock Source XTAL Idle TOSC WDT XTAL Power-save TOSC WDT XTAL Power-down TOSC WDT GCK5 Active Not Available Not Available Inactive Not Available Not Available Inactive Not Available Not Available GCK6 Active Active Active Inactive Active Active Inactive Inactive Active
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Rev. 1138F-FPSLI-06/02
Figure 12. Clocking (for One Column of Cells)
} FCK(1)
} GCK1 - GCK8
"1"
Global Clock Line (Buried)
Express Bus (Plane 4; Half Length at Edge)
"1" Repeater
"1"
"1"
Note:
1. Two on left edge column of the embedded FPGA array only.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 13. Set/Reset (for One Column of Cells)
Each Cell has a Programmable Set or Reset
Repeater
"1"
Global Set/Reset Line (Buried)
"1"
Express Bus (Plane 5; Half Length at Edge)
"1"
"1"
Any User I/O can Drive Global Set/Reset Line
Some of the bus resources on the embedded FPGA core are used as dual-function resources. Table 3 shows which buses are used in a dual-function mode and which bus plane is used. The FPGA software tools are designed to automatically accommodate dual-function buses in an efficient manner.
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Rev. 1138F-FPSLI-06/02
Table 3. Dual-function Buses
Function Cell Output Enable Type Local Plane(s) 5 Direction Horizontal and Vertical Vertical Vertical Vertical Bus full length at array edge bus in first column to left of RAM block Bus full length at array edge bus in first column to left of RAM block Buses full length at array edge buses in second column to left of RAM block Comments
FreeRAM Output Enable FreeRAM Write Enable FreeRAM Address
Express Express Express
2 1 1-5
FreeRAM Data In FreeRAM Data Out Clocking Set/Reset
Local Local Express Express
1 2 4 5
Horizontal Horizontal Vertical Vertical Bus full length at array edge Bus full length at array edge
Figure 14. Primary I/O
CELL
TRI-STATE
"0" "1"
VCC
PULL-UP
DRIVE
"0"
PAD
"1" CELL
RST TTL/CMOS GND SCHMITT DELAY CLK
PULL-DOWN
RST
CLK
CELL
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 15. Secondary I/O
TRI-STATE
"0" "1"
VCC
PULL-UP "0"
DRIVE
CELL
"1" PAD
RST
PULL-DOWN
TTL/CMOS
GND
SCHMITT DELAY
CLK
RST
CLK
CELL
Figure 16. Primary and Secondary I/Os
p cell s s
p cell s
p cell s
p cell s
p
p cell s s
p cell s
p cell s
p cell s
s = secondary I/O p = primary I/O
p cell
p cell
p cell
p cell
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Rev. 1138F-FPSLI-06/02
Figure 17. Corner I/Os
PULL-DOWN PULL-DOWN PULL-UP PULL-UP
PAD
PAD
VCC
GND TTL/CMOS SCHMITT DELAY
CLK RST
VCC
GND TTL/CMOS SCHMITT DELAY
CLK RST
DRIVE TRI-ST ATE
DRIVE TRI-ST ATE
RST CLK
RST CLK
"0" "1"
"0" "1"
"0"
TRI-STATE
VCC
PULL-UP
DRIVE
PAD
RST CLK
"0" "1"
"0" "1"
"0"
"1" CELL CELL
PULL-DOWN
TTL/CMOS SCHMITT DELAY
CLK RST
GND
"1"
CELL
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
FPGA/AVR Interface and System Control
The FPGA and AVR share a flexible interface which allows for many methods of system integration. * * Both FPGA and AVR share access to the 15 ns dual-port SRAM. The AVR data bus interfaces directly into the FPGA busing resources, effectively treating the FPGA as a large I/O device. Users have complete flexibility on the types of additional peripherals which are placed and routed inside the FPGA user logic. Up to 16 decoded address lines are provided into the FPGA. Up to 16 interrupts are available from the FPGA to the AVR. The AVR can reprogram the FPGA during operation to create a dynamic reconfigurable system (Cache Logic).
* * *
FPGA/AVR Interface- Memory-mapped Peripherals
The FPGA core can be directly accessed by the AVR core, see Figure 18. Four memory locations in the AVR memory map are decoded into 16 select lines (8 for AT94K05) and are presented to the FPGA along with the AVR 8-bit data bus. The FPGA can be used to create additional custom peripherals for the AVR microcontroller through this interface. In addition there are 16 interrupt lines (8 for AT94K05) from the FPGA back into the AVR interrupt controller. Programmable peripherals or regular logic can use these interrupt lines. Full support for programmable peripherals is available within the System Designer tool suite. Figure 18. FPGA/AVR Interface: Interrupts and Addressing
Up to 16 Memory-mapped Decoded Address Lines from 4 I/O Memory ADDRESS Space Addresses DECODER 4:16 DECODE 8-bit Data Out
I/O Memory Address Bus
FPGAIORE EMBEDDED AVR CORE
EMBEDDED FPGA CORE
8-bit Bi-directional Data Bus 8-bit Data In FPGAIOWE
Up to 16 Interrupt Lines from FPGA to AVR - Various Priority Levels
The FPGA I/O selection is controlled by the AVR. This is described in detail beginning on page 53. The FPGA I/O interrupts are described beginning on page 57.
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Rev. 1138F-FPSLI-06/02
Program and Data SRAM
Up to 36 Kbytes of 15 ns dual-port SRAM reside between the FPGA and the AVR. This SRAM is used by the AVR for program instruction and general-purpose data storage. The AVR is connected to one side of this SRAM; the FPGA is connected to the other side. The port connected to the FPGA is used to store data without using up bandwidth on the AVR system data bus. The FPGA core communicates directly with the data SRAM(1) block, viewing all SRAM memory space as 8-bit memory.
Note: 1. The unused bits for the FPGA-SRAM address must tie to `0' because there is no pull-down circuitry.
For the AT94K10 and AT94K40, the internal program and data SRAM is divided into three blocks: 10 Kbytes x 16 dedicated program SRAM, 4 Kbytes x 8 dedicated data SRAM and 6 Kbytes x 16 or 12 Kbytes x 8 configurable SRAM, which may be swapped between program and data memory spaces in 2 Kbytes x 16 or 4 Kbytes x 8 partitions. For the AT94K05, the internal program and data SRAM is divided into three blocks: 4 Kbytes 16 dedicated program SRAM, 4 Kbytes x 8 dedicated data SRAM and 6 Kbytes x 16 or 12 Kbytes x 8 configurable SRAM, which may be swapped between program and data memory spaces in 2 Kbytes x 16 or 4 Kbytes x 8 partitions. The addressing scheme for the configurable SRAM partitions prevents program instructions from overwriting data words and vice versa. Once configured (SCR41:40 - See "System Control Register - FPGA/AVR" on page 30.), the program memory space remains isolated from the data memory space. SCR41:40 controls internal muxes. Write enable signals allow the memory to be safely segmented. Figure 19 shows the FPSLIC configurable allocation SRAM memory.
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AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Figure 19. FPSLIC Configurable Allocation SRAM Memory(1)(2)
Program SRAM Memory Memory Partition is User Defined during Development SOFT "BOOT BLOCK" FIXED 10K x 16 4 Kbytes x 16 (94K05)
(1)
$0000 $07FF
Data SRAM Memory $3FFF OPTIONAL 4 Kbytes x 8 $3000 $2FFF OPTIONAL 4 Kbytes x 8 $2000 $1FFF OPTIONAL 4 Kbytes x 8 $1000 $0FFF FIXED 4 Kbytes x 8 $005F DATA SRAM FPGA ACCESS ONLY AVR MEMORY MAPPED I/O AVR REG. SPACE (2)
$27FF $2800
OPTIONAL 2 Kbytes x 16 $2FFF $3000 OPTIONAL 2 Kbytes x 16 $37FF $3800 OPTIONAL 2 Kbytes x 16 $3FFF
$001F $0000
Notes:
1. The Soft "BOOT BLOCK" is an area of memory that is first loaded when the part is powered up and configured. The remainder of the memory can be reprogrammed while the device is in operation for switching functions in and out of memory. The Soft "BOOT BLOCK" can only be programmed by a full device configuration on power-up. 2. The lower portion of the Data memory is not shared between the AVR and FPGA. The AVR uses addresses $0000 - $001F for the AVR CPU general working registers. $001F - $005F are the addresses used for Memory Mapped I/O and store the information in dedicated registers. Therefore, on the FPGA side $0000 - $005F are available for data that is only needed by the FPGA.
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Rev. 1138F-FPSLI-06/02
Data SRAM Access by FPGA - FPGAFrame Mode
The FPGA user logic has access to the data SRAM directly through the FPGA side of the dual-port memory, see Figure 20. A single bit in the configuration control register (SCR63 - see "System Control Register - FPGA/AVR" on page 30) enables this interface. The interface is disabled during configuration downloads. Express buses on the East edge of the array are used to interface the memory. Full read and write access is available. To allow easy implementation, the interface itself is dedicated in routing resources, and is controlled in the System Designer software suite using the AVR FPGA interface dialog. Figure 20. Internal SRAM Access - Normal Use
16 Address Lines: FPGA Edge Express Buses
16-bit Data Address Bus
WE FPGA EMBEDDED FPGA CORE CLK FPGA SCR38 8-bit Data Read 4 Kbytes x 8 UP TO 16 Kbytes x 8 DATA SRAM
WE AVR RE AVR CLK AVR EMBEDDED AVR CORE
8-bit Data Read/Write
8-bit Data Write
B Side A Side
Once the SCR63 bit is set there is no additional read enable from the FPGA side. This means that the read is always enabled. You can also perform a read or write from the AVR at the same time as an FPGA read or write. If there is a possibility of a write address being accessed by both devices at the same time, the designer should add arbitration to the FPGA Logic to control who has priority. In most cases the AVR would be used to restrict access by the FPGA using the FMXOR bit, see "Software Control Register - SFTCR" on page 51. You can read from the same location from both sides simultaneously. SCR bit 38 controls the polarity of the clock to the SRAM from the AT40K FPGA.
SRAM Access by FPGA/AVR
Accessing and Modifying the Program Memory from the AVR
This option is used to allow for code (Program Memory) changes.
The FPSLIC SRAM is up to 36 x 8 Kbytes of dual port, see Figure 19): * * * The A side (port) is accessed by the AVR. The B side (port) is accessed by the FPGA/Configuration Logic. The B side (port) can be accessed by the AVR with ST and LD instructions in DBG mode for code self-modify.
Structurally, the [(n * 2) Kbytes 8] memory is built from (n)2 Kbytes 8 blocks, numbered SRAM0 through SRAM(n).
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AT94K Series FPSLIC
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AT94K Series FPSLIC
A Side The A side is partitioned into Program memory and Data memory: * * Program memory is 16-bit words. Program memory address $0000 always starts in the highest two SRAMs (n - 1, n) [SRAMn - 1 (low byte) and SRAMn (high byte)] (SRAM labels are for layout, the addressing scheme is transparent to the AVR PC). System configuration determines the higher addresses for program memory: - SCR bits 41 = 0 : 40 = 0, program memory extended from $2800 - $3FFF - SCR bits 41 = 0 : 40 = 1, program memory extended from $2800 - $37FF - SCR bits 41 = 1 : 40 = 0, program memory extended from $2800 - $2FFF - SCR bits 41 = 1 : 40 = 1, no extra program memory * Extended program memory is always lost to extended data memory from SRAM2/3 down to SRAM6/7, see Table 4.
*
Table 4. AVR Program Decode for SRAM 2:7 (16K16)
Address Range $3FFF - $3800 $3FFF - $3800 $37FF - $3000 $37FF - $3000 $2FFF - $2800 $2FFF - $2800 $27FF - $2000 $27FF - $2000 $1FFF - $1800 $1FFF - $1800 $17FF - $1000 $17FF - $1000 $0FFF - $0800 $0FFF - $0800 $07FF - $0000 $07FF - $0000 SRAM 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 n = 17 Comments CR41:40 = 00 CR41:40 = 00,01 CR41:40 = 00,01,10 AVR AVR AVR AVR AVR AVR AVR AVR AVR AVR Program Program Program Program Program Program Program Program Program Program Read-only Read-only Read-only Read-only Read-only Read-only Read-only Read-only Read-only Read-only
* * *
Data memory is 8-bit words. Data memory address $0000 always starts in SRAM0 (SRAM labels are for layout, the addressing scheme is transparent to AVR data read/write). System configuration determines the higher address for data memory: - - - - SCR bits 41 = 0 : 40 = 0, no extra data memory SCR bits 41 = 0 : 40 = 1, data memory extended from $1000 - $1FFF SCR bits 41 = 1 : 40 = 0, data memory extended from $1000 - $2FFF SCR bits 41 = 1 : 40 = 1, data memory extended from $1000 - $3FFF
*
Extended data memory is always lost to extended program memory from SRAM7 up to SRAM2 in 2 x SRAM blocks, see Table 5.
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Table 5. AVR Data Decode for SRAM 0:17 (16K8)
Address Range $07FF - $0000 $0FFF - $0800 $17FF - $1000 $1FFF - $1800 $27FF - $2000 $2FFF - $2800 $37FF - $3000 $3FFF - $3800 SRAM 00 01 02 03 04 05 06 07 Comments AVR Data Read/Write AVR Data Read/Write CR41:40 = 11,10,01 CR41:40 = 11,10 CR41:40 = 11
B Side
The B side is not partitioned; the FPGA (and AVR debug mode) views the memory space as 36 x 8 Kbytes. * * The B side is accessed by the FPGA/Configuration Logic. The B side is accessed by the AVR with ST and LD instructions in DBG mode for code self-modify. To activate the debug mode and allow the AVR to access the program code space (with ST - see Figure 21 - and LD - see Figure 22 - instructions), the DBG bit (bit 1) of the SFTCR $3A ($5A) register has to be set. When this bit is set, SCR36 and SCR37 are ignored - you can overwrite anything in the AVR program memory. The FPGA memory access interface should be disabled while in debug mode. This is to ensure that there is no contention between the FPGA address and data signals and the AVR-generated address and data signals. To ensure the AVR has control over the "B side" memory interface, the FMXOR bit (bit 3) of the SFTCR $3A ($5A) register should be used in conjunction with the SCR63 system control register bit. The FMXOR bit is XORed with the System Control Register's Enable FPGA SRAM Interface bit (SCR63). The behavior when this bit is set to 1 is dependent on how the SCR was initialized. If the Enable FPGA SRAM Interface bit (SCR63) in the SCR is 0, the FMXOR bit enables the FPGA SRAM Interface when set to 1. If the Enable FPGA SRAM Interface bit in the SCR is 1, the FMXOR bit disables the FPGA SRAM Interface when set to 1. During AVR reset, the FMXOR bit is cleared by the hardware. Even though the FPGA (and AVR debug mode) views the memory space as 36 x 8 Kbytes, an awareness of the 2K x 8 partitions (or SRAM labels) is required if Frame (and AVR debug mode) read/writes are to be meaningful to the AVR. * * AVR data to FPGA addressing is 1:1 mapping. AVR program to FPGA addressing requires 16-bit to 8-bit mapping and an understanding of the partitions in Table 6.
Table 6. Summary Table for AVR and FPGA SRAM Addressing
SRAM 00 01 02(1) 03 04
(1) (1)
FPGA and AVR DBG Address Range $0000 - $07FF $0800 - $0FFF $1000 - $17FF $1800 - $1FFF $2000 - $27FF
AVR Data Address Range $0000 - $07FF $0800 - $0FFF $1000 - $17FF $1800 - $1FFF $2000 - $27FF
AVR PC Address Range
$3800 - $3FFF (LS Byte) $3800 - $3FFF (MS Byte) $3000 - $37FF (LS Byte)
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AT94K Series FPSLIC
Table 6. Summary Table for AVR and FPGA SRAM Addressing (Continued)
SRAM 05
(1)
FPGA and AVR DBG Address Range $2800 - $2FFF $3000 - $37FF $3800 - $3FFF $4000 - $47FF $4800 - $4FFF $5000 - $57FF $5800 - $5FFF $6000 - $67FF $6800 - $6FFF $7000 - $77FF $7800 - $7FFF $8000 - $87FF $8800 - $8FFF
AVR Data Address Range $2800 - $2FFF $3000 - $37FF $3800 - $3FFF
AVR PC Address Range $3000 - $37FF (MS Byte) $2800 - $2FFF (LS Byte) $2800 - $2FFF (MS Byte) $2000 - $27FF (LS Byte) $2000 - $27FF (MS Byte) $1800 - $1FFF (LS Byte) $1800 - $1FFF (MS Byte) $1000 - $17FF (LS Byte) $1000 - $17FF (MS Byte) $0800 - $0FFF (LS Byte) $0800 - $0FFF (MS Byte) $0000 - $07FF (LS Byte) $0000 - $07FF (MS Byte)
06(1) 07(1) 08 09 10 11 12 13 14 15 16 17 = n Note:
1. Whether these SRAMs are "Data" or "Program" depends on the SCR40 and SCR41 values.
Example: Frame (and AVR debug mode) write of instructions to associated AVR PC addresses, see Table 7 and Table 8. Table 7. AVR PC Addresses
AVR PC 0FFE 0FFF 1000 1001 Instruction 9B28 CFFE B300 9A39
Table 8. Frame Addresses
Frame Address 77FE 77FF 6000 6001 7FFE 7FFF 6800 6801 Frame Data 28 FE 00 39 9B CF B3 9A
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Rev. 1138F-FPSLI-06/02
Figure 21. AVR SRAM Data Memory Write Using "ST" Instruction
CLOCK
RAMWE
RAMADR
VALID
DBUS
VALID
DBUSOUT (REGISTERED) ST cycle 1
VALID ST cycle 2 next instruction
Figure 22. AVR SRAM Data Memory Read Using "LD" Instruction
CLOCK
RAMRE
RAMADR
VALID
DBUS LD cycle 1
VALID LD cycle 2 next instruction
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AT94K Series FPSLIC
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AT94K Series FPSLIC
AVR Cache Mode
The AVR has the ability to cache download the FPGA memory. The AVR has direct access to the data buses of the FPGA's configuration SRAM and is able to download bitstreams. AVR Cache access of configuration SRAM is not available during normal configuration downloads. The Cache Logic port in the AVR is located in the I/O memory map. Three registers, FPGAX, FPGAY FPGAZ, control the address written to inside the FPGA; and FPGAD in the AVR memory map controls the Data. Registers FPGAX, FPGAY and FPGAZ are write only, see Figure 23. Figure 23. Internal FPGA Configuration Access
Configuration Logic 32-BIT CONFIGURATION WORD EMBEDDED AVR CORE FPGAX [7:0] FPGAY [7:0] FPGAZ [7:0] FPGAD [7:0] Memory-mapped Location Memory-mapped Location Memory-mapped Location Memory-mapped Location
EMBEDDED FPGA CORE 8-bit Configuration Memory Write Data 24-bit Address Write
(Operation is not interrupted during Cache Logic loading)
CACHEIOWE
Configuration Clock - Each tick is generated when the Memorymapped I/O location FPGAD is written to inside the AVR.
The AVR Cache Logic access mode is write only. Transfers may be aborted at any time due to AVR program wishes or external interrupts. The FPGA CHECK function is not supported by the AVR Cache mode. A typical application for this mode is for the AVR to accept serial data through a UART for example, and port it as configuration data to the FPGA, thereby affecting a download, or allowing reconfigurable systems where the FPGA is updated algorithmically by the AVR. For more information, refer to the "AT94K Series Configuration" application note available on the Atmel web site, at: http://www.atmel.com/atmel/acrobat/doc2313.pdf.
Resets
The user must have the flexibility to issue resets and reconfiguration commands to separate portions of the device. There are two Reset pins on the FPSLIC device. The first, RESET, results in a clearing of all FPGA configuration SRAM and the System Control Register, and initiates a download if in mode 0. The AVR will stop and be reset. A second reset pin, AVRReset, is implemented to reset the AVR portion of the FPSLIC functional blocks. This is described in the "Reset Sources" on page 61.
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Rev. 1138F-FPSLI-06/02
System Control
Configuration Modes The AT94K family has four configuration modes controlled by mode pins M0 and M2, see Table 9. Table 9. Configuration Modes
M2 0 0 1 1 M0 0 1 0 1 Name Mode 0 - Master Serial Mode 1 - Slave Serial Cascade Mode 2 - Reserved Mode 3 - Reserved
Modes 2 and 3 are reserved and are used for factory test. Modes 0 and 1 are pin-compatible with the appropriate AT40K counterpart. AVR I/O will be taken over by the configuration logic for the CHECK pin during both modes. Refer to the "AT94K Series Configuration" application note for details on downloading bitstreams. System Control Register - FPGA/AVR The configuration control register in the FPSLIC consists of 8 bytes of data, which are loaded with the FPGA/Prog. Code at power-up from external nonvolatile memory. FPSLIC System Control Register values, see Table 10, can be set in the System Designer software. Recommended defaults are included in the software. Table 10. FPSLIC System Control Register
Bit SCR0 - SCR1 SCR2 Description Reserved 0 = Enable Cascading 1 = Disable Cascading SCR2 controls the operation of the dual-function I/O CSOUT. When SCR2 is set, the CSOUT pin is not used by the configuration during downloads, set this bit for configurations where two or more devices are cascaded together. This applies for configuration to another FPSLIC device or to an FPGA. 0 = Check Function Enabled 1 = Check Function Disabled SCR3 controls the operation of the CHECK pin and enables the Check Function. When SCR3 is set, the dual use AVR I/O/CHECK pin is not used by the configuration during downloads, and can be used as AVR I/O. 0 = Memory Lockout Disabled 1 = Memory Lockout Enabled SCR4 is the Security Flag and controls the writing and checking of configuration memory during any subsequent configuration download. When SCR4 is set, any subsequent configuration download initiated by the user, whether a normal download or a CHECK function download, causes the INIT pin to immediately activate. CON is released, and no further configuration activity takes place. The download sequence during which SCR4 is set is NOT affected. The Control Register write is also prohibited, so bit SCR4 may only be cleared by a power-on reset or manual reset. Reserved
SCR3
SCR4
SCR5
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Table 10. FPSLIC System Control Register
Bit SCR6 Description 0 = OTS Disabled 1 = OTS Enabled Setting SCR6 makes the OTS (output tri-state) pin an input which controls the global tri-state control for all user I/O. This junction allows the user at any time to tristate all user I/O and isolate the chip. Reserved 0 = CCLK Normal Operation 1 = CCLK Continues After Configuration. Setting bit SCR13 allows the CCLK pin to continue to run after configuration download is completed. This bit is valid for Master mode, mode 0 only. The CCLK is not available internally on the device. If it is required in the design, it must be connected to another device I/O. Reserved 0 = GCK 0:7 Always Enabled 1 = GCK 0:7 Disabled During Internal and External Configuration Download. Setting SCR16:SCR23 allows the user to disable the input buffers driving the global clocks. The clock buffers are enabled and disabled synchronously with the rising edge of the respective GCK signal, and stop in a High "1" state. Setting one of these bits disables the appropriate GCK input buffer only and has no effect on the connection from the input buffer to the FPGA array. 0 = FCK 0:1 Always Enabled 1 = FCK 0:1 Disabled During Internal and External Configuration Download. Setting SCR24:SCR25 allows the user to disable the input buffers driving the fast clocks. The clock buffers are enabled and disabled synchronously with the rising edge of the respective FCK signal, and stop in a High "1" state. Setting one of these bits disables the appropriate FCK input buffer only and has no effect on the connection from the input buffer to the FPGA array. 0 = Disable On-chip Debugger 1 = Enable On-chip Debugger. JTAG Enable, SCR27, must also be set (one) and the configuration memory lockout, SCR4, must be clear (zero) for the user to have access to internal scan chains. 0 = Disable TAP at user FPGA I/O Ports 1 = Enable TAP at user FPGA I/O Ports. Device ID scan chain and AVR I/O boundary scan chain are available. The user must set (one) the On-chip Debug Enable, SCR26, and must keep the configuration memory lockout, SCR4, clear (zero) for the user to have access to internal scan chains. Reserved 0 = Global Set/Reset Normal 1 = Global Set/Reset Active (Low) During Internal and External Configuration Download. SCR30 allows the Global set/reset to hold the core DFFs in reset during any configuration download. The Global set/reset net is released at the end of configuration download on the rising edge of CON, if set. 0 = Disable I/O Tri-state 1 = I/O Tri-state During (Internal and External) Configuration Download. SCR31 forces all user defined I/O pins to go tri-state during configuration download. Tri-state is released at the end of configuration download on the rising edge of CON, if set.
SCR7 - SCR12 SCR13
SCR14 - SCR15 SCR16 - SCR23
SCR24 - SCR25
SCR26
SCR27
SCR28 - SCR29 SCR30
SCR31
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Rev. 1138F-FPSLI-06/02
Table 10. FPSLIC System Control Register
Bit SCR32 - SCR34 SCR35 Description Reserved 0 = AVR Reset Pin Disabled 1 = AVR Reset Pin Enabled (active Low Reset) SCR35 allows the AVR Reset pin to reset the AVR only. 0 = Protect AVR Program SRAM 1 = Allow Writes to AVR Program SRAM (Excluding Boot Block) SCR36 protects AVR program code from writes by the FPGA. 0 = AVR Program SRAM Boot Block Protect 1 = AVR Program SRAM Boot Block Allows Overwrite 0 = (default) Frame Clock Inverted to AVR Data/Program SRAM 1 = Non-inverting Clock Into AVR Data/Program SRAM Reserved SCR41 = 0, SCR40 = 0 16 Kbytes x 16 Program/4 Kbytes x 8 Data SCR41 = 0, SCR40 = 1 14 Kbytes x 16 Program/8 Kbytes x 8 Data SCR41 = 1, SCR40 = 0 12 Kbytes x 16 Program/12 Kbytes x 8 Data SCR41 = 1, SCR40 = 1 10 Kbytes x 16 Program/16 Kbytes x 8 Data SCR40 : SCR41 AVR program/data SRAM partitioning (set by using the AT94K Device Options in System Designer). Reserved 0 = EXT-INT0 Driven By Port E<4> 1 = EXT-INT0 Driven By INTP0 pad SCR48 : SCR53 Defaults dependent on package selected. 0 = EXT-INT1 Driven By Port E<5> 1 = EXT-INT1 Driven By INTP1 pad SCR48 : SCR53 Defaults dependent on package selected. 0 = EXT-INT2 Driven By Port E<6> 1 = EXT-INT2 Driven By INTP2 pad SCR48 : SCR53 Defaults dependent on package selected. 0 = EXT-INT3 Driven By Port E<7> 1 = EXT-INT3 Driven By INTP3 pad SCR48 : SCR53 Defaults dependent on package selected. 0 = UART0 Pins Assigned to Port E<1:0> 1 = UART0 Pins Assigned to UART0 pads SCR48 : SCR53 Defaults dependent on package selected. 0 = UART1 Pins Assigned to Port E<3:2> 1 = UART1 Pins Assigned to UART1 pads SCR48 : SCR53 Defaults dependent on package selected. On packages less than 144-pins, there is reduced access to AVR ports. Port D is not available externally in the smallest package and Port E becomes dual-purpose I/O to maintain access to the UARTs and external interrupt pins. The Pin List (East Side) on page 177 shows exactly which pins are available in each package. 0 = AVR Port D I/O With 6 mA Drive 1 = AVR Port D I/O With 20 mA Drive 0 = AVR Port E I/O With 6 mA Drive 1 = AVR Port E I/O With 20 mA Drive
SCR36
SCR37 SCR38 SCR39 SCR40 - SCR41
SCR 42 SCR47 SCR48
SCR49
SCR50
SCR51
SCR52
SCR53
SCR54 SCR55
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Table 10. FPSLIC System Control Register
Bit SCR56 SCR57 SCR58 - SCR59 SCR60 - SCR61 Description 0 = Disable XTAL Pin (Rfeedback) 1 = Enable XTAL Pin (Rfeedback) 0 = Disable TOSC2 Pin (Rfeedback) 1 = Enable TOSC2 Pin (Rfeedback) Reserved SCR61 = 0, SCR60 = 0 "1" SCR61 = 0, SCR60 = 1 AVR System Clock SCR61 = 1, SCR60 = 0 Timer Oscillator Clock (TOSC1)(1) SCR61 = 1, SCR60 = 1 Watchdog Clock Global Clock 6 mux select (set by using the AT94K Device Options in System Designer). Note: SCR62 SCR63 1. The AS2 bit must be set in the ASSR register.
0 = Disable CacheLogic Writes to FPGA by AVR 1 = Enable CacheLogic Writes to FPGA by AVR 0 = Disable Access (Read and Write) to SRAM by FPGA 1 = Enable Access (Read and Write) to SRAM by FPGA
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Rev. 1138F-FPSLI-06/02
AVR Core and Peripherals
* * * * * * * * * * * AVR Core Watchdog Timer/On-chip Oscillator Oscillator-to-Internal Clock Circuit Oscillator-to-Timer/Counter for Real-time Clock 16-bit Timer/Counter and Two 8-bit Timer/Counters Interrupt Unit Multiplier UART (0) UART (1) I/O Port D (full 8 bits available on 144-pin or higher devices) I/O Port E
The embedded AVR core is a low-power CMOS 8-bit microcontroller based on the AVR RISC architecture. The embedded AVR core achieves throughputs approaching 1 MIPS per MHz by executing powerful instructions in a single-clock-cycle, and allows the system architect to optimize power consumption versus processing speed. The AVR core is based on an enhanced RISC architecture that combines a rich instruction set with 32 x 8 general-purpose working registers. All the 32 x 8 registers are directly connected to the Arithmetic Logic Unit (ALU), allowing two independent register bytes to be accessed in one single instruction executed in one clock cycle. The resulting architecture is more code efficient while achieving throughputs up to ten times faster than conventional CISC microcontrollers. The embedded AVR core provides the following features: 16 general-purpose I/O lines, 32 x 8 general-purpose working registers, Real-time Counter (RTC), 3 flexible timer/counters with compare modes and PWM, 2 UARTs, programmable Watchdog Timer with internal oscillator, 2-wire serial port, and three software-selectable Power-saving modes. The Idle mode stops the CPU while allowing the SRAM, timer/counters, two-wire serial port, and interrupt system to continue functioning. The Power-down mode saves the register contents but freezes the oscillator, disabling all other chip functions until the next interrupt or hardware reset. In Power-save mode, the timer oscillator continues to run, allowing the user to maintain a timer base while the rest of the device is sleeping. The embedded AVR core is supported with a full suite of program and system development tools, including C compilers, macro assemblers, program debugger/simulators and evaluation kits.
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AT94K Series FPSLIC
Instruction Set Nomenclature (Summary)
Status Register (SREG) The complete "AVR Instruction Set" document is available on the Atmel web site, at http://www.atmel.com/atmel/acrobat/doc0856.pdf.
SREG: C: Z: N: V: S: H: T: I:
Status register Carry flag in status register Zero flag in status register Negative flag in status register Two's complement overflow indicator N V, For signed tests Half-carry flag in the status register Transfer bit used by BLD and BST instructions Global interrupt enable/disable flag Destination (and source) register in the register file Source register in the register file Result after instruction is executed Constant data Constant address Bit in the register file or I/O register (0 b 7) Bit in the status register (0 s 2) Indirect address register (X = R27:R26, Y = R29:R28 and Z = R31:R30) I/O location address Displacement for direct addressing (0 q 63)
Registers and Operands
Rd: Rr: R: K: k: b: s: X,Y,Z: A: q:
I/O Registers
Stack
STACK: Stack for return address and pushed registers SP: Stack Pointer to STACK Flag affected by instruction Flag cleared by instruction Flag set by instruction Flag not affected by instruction
Flags
: 0: 1: -:
The instructions EIJMP, EICALL, ELPM, GPM, ESPM (from the megaAVR Instruction Set) are not supported in the FPSLIC device.
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Rev. 1138F-FPSLI-06/02
Conditional Branch Summary
Test Rd > Rr Rd Rr Rd = Rr Rd Rr Rd < Rr Rd > Rr Rd Rr Rd = Rr Rd Rr Rd < Rr Carry Negative Overflow Zero Boolean Z*(N V) = 0 (N V) = 0 Z=1 Z+(N V) = 1 (N V) = 1 C+Z=0 C=0 Z=1 C+Z=1 C=1 C=1 N=1 V=1 Z=1 Mnemonic BRLT BRGE BREQ BRGE BRLT BRLO BRSH/BRCC BREQ BRSH BRLO/BRCS BRCS BRMI BRVS BREQ Complementary Rd Rr Rd < Rr Rd Rr Rd > Rr Rd Rr Rd Rr Rd < Rr Rd Rr Rd > Rr Rd Rr No Carry Positive No Overflow Not Zero Boolean Z+(N V) = 1 (N V) = 1 Z=0 Z*(N V) = 0 (N V) = 0 C+Z=1 C=1 Z=0 C+Z=0 C=0 C=0 N=0 V=0 Z=0 Mnemonic BRGE BRLT BRNE BRLT BRGE BRSH BRLO/BRCS BRNE BRLO BRSH/BRCC BRCC BRPL BRVC BRNE Comment Signed Signed Signed Signed Signed Unsigned Unsigned Unsigned Unsigned Unsigned Simple Simple Simple Simple
Complete Instruction Set Summary
Instruction Set Summary
Mnemonics Operands Description Operation Arithmetic and Logic Instructions ADD ADC ADIW SUB SUBI SBC SBCI SBIW AND ANDI OR ORI EOR COM NEG SBR Rd, Rr Rd, Rr Rd, K Rd, Rr Rd, K Rd, Rr Rd, K Rd, K Rd, Rr Rd, K Rd, Rr Rd, K Rd, Rr Rd Rd Rd, K Add without Carry Add with Carry Add Immediate to Word Subtract without Carry Subtract Immediate Subtract with Carry Subtract Immediate with Carry Subtract Immediate from Word Logical AND Logical AND with Immediate Logical OR Logical OR with Immediate Exclusive OR One's Complement Two's Complement Set Bit(s) in Register Rd Rd + Rr Rd Rd + Rr + C Rd+1:Rd Rd+1:Rd + K Rd Rd - Rr Rd Rd - K Rd Rd - Rr - C Rd Rd - K - C Rd+1:Rd Rd+1:Rd - K Rd Rd * Rr Rd Rd * K Rd Rd v Rr Rd Rd v K Rd Rd Rr Rd $FF - Rd Rd $00 - Rd Rd Rd v K Z,C,N,V,S,H Z,C,N,V,S,H Z,C,N,V,S Z,C,N,V,S,H Z,C,N,V,S,H Z,C,N,V,S,H Z,C,N,V,S,H Z,C,N,V,S Z,N,V,S Z,N,V,S Z,N,V,S Z,N,V,S Z,N,V,S Z,C,N,V,S Z,C,N,V,S,H Z,N,V,S 1 1 2 1 1 1 1 2 1 1 1 1 1 1 1 1 Flags #Clock
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AT94K Series FPSLIC
Instruction Set Summary (Continued)
Mnemonics CBR INC DEC TST CLR SER MUL MULS MULSU FMUL FMULS FMULSU Operands Rd, K Rd Rd Rd Rd Rd Rd, Rr Rd, Rr Rd, Rr Rd, Rr Rd, Rr Rd, Rr Description Clear Bit(s) in Register Increment Decrement Test for Zero or Minus Clear Register Set Register Multiply Unsigned Multiply Signed Multiply Signed with Unsigned Fractional Multiply Unsigned Fractional Multiply Signed Fractional Multiply Signed with Unsigned Operation Rd Rd * ($FFh - K) Rd Rd + 1 Rd Rd - 1 Rd Rd * Rd Rd Rd Rd Rd $FF R1:R0 Rd x Rr (UU) R1:R0 Rd x Rr (SS) R1:R0 Rd x Rr (SU) R1:R0 (Rd x Rr)<<1 (UU) R1:R0 (Rd x Rr)<<1 (SS) R1:R0 (Rd x Rr)<<1 (SU) Flags Z,N,V,S Z,N,V,S Z,N,V,S Z,N,V,S Z,N,V,S None Z,C Z,C Z,C Z,C Z,C Z,C #Clock 1 1 1 1 1 1 2 2 2 2 2 2
Branch Instructions RJMP IJMP JMP RCALL ICALL CALL RET RETI CPSE CP CPC CPI SBRC SBRS SBIC SBIS BRBS BRBC BREQ BRNE BRCS BRCC Rd, Rr Rd, Rr Rd, Rr Rd, K Rr, b Rr, b A, b A, b s, k s, k k k k k k k k k Relative Jump Indirect Jump to (Z) Jump Relative Call Subroutine Indirect Call to (Z) Call Subroutine Subroutine Return Interrupt Return Compare, Skip if Equal Compare Compare with Carry Compare with Immediate Skip if Bit in Register Cleared Skip if Bit in Register Set Skip if Bit in I/O Register Cleared Skip if Bit in I/O Register Set Branch if Status Flag Set Branch if Status Flag Cleared Branch if Equal Branch if Not Equal Branch if Carry Set Branch if Carry Cleared PC PC + k + 1 PC(15:0) Z PC k PC PC + k + 1 PC(15:0) Z PC k PC STACK PC STACK if (Rd = Rr) PC PC + 2 or 3 Rd - Rr Rd - Rr - C Rd - K if (Rr(b) = 0) PC PC + 2 or 3 if (Rr(b) = 1) PC PC + 2 or 3 if(I/O(A,b) = 0) PC PC + 2 or 3 If(I/O(A,b) = 1) PC PC + 2 or 3 if (SREG(s) = 1) then PC PC+k+1 if (SREG(s) = 0) then PC PC+k+1 if (Z = 1) then PC PC + k + 1 if (Z = 0) then PC PC + k + 1 if (C = 1) then PC PC + k + 1 if (C = 0) then PC PC + k + 1 None None None None None None None I None Z,C,N,V,S,H Z,C,N,V,S,H Z,C,N,V,S,H None None None None None None None None None None 2 2 3 3 3 4 4 4 1/2/3 1 1 1 1/2/3 1/2/3 1/2/3 1/2/3 1/2 1/2 1/2 1/2 1/2 1/2
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Instruction Set Summary (Continued)
Mnemonics BRSH BRLO BRMI BRPL BRGE BRLT BRHS BRHC BRTS BRTC BRVS BRVC BRIE BRID Operands k k k k k k k k k k k k k k Description Branch if Same or Higher Branch if Lower Branch if Minus Branch if Plus Branch if Greater or Equal, Signed Branch if Less Than, Signed Branch if Half-carry Flag Set Branch if Half-carry Flag Cleared Branch if T Flag Set Branch if T Flag Cleared Branch if Overflow Flag is Set Branch if Overflow Flag is Cleared Branch if Interrupt Enabled Branch if Interrupt Disabled Operation if (C = 0) then PC PC + k + 1 if (C = 1) then PC PC + k + 1 if (N = 1) then PC PC + k + 1 if (N = 0) then PC PC + k + 1 if (N V= 0) then PC PC + k + 1 if (N V= 1) then PC PC + k + 1 if (H = 1) then PC PC + k + 1 if (H = 0) then PC PC + k + 1 if (T = 1) then PC PC + k + 1 if (T = 0) then PC PC + k + 1 if (V = 1) then PC PC + k + 1 if (V = 0) then PC PC + k + 1 if (I = 1) then PC PC + k + 1 if (I = 0) then PC PC + k + 1 Flags None None None None None None None None None None None None None None #Clock 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2
Data Transfer Instructions MOV MOVW LDI LDS LD LD LD LD LD LD LDD LD LD LD LDD STS ST ST ST ST ST Rd, Rr Rd, Rr Rd, K Rd, k Rd, X Rd, X+ Rd, -X Rd, Y Rd, Y+ Rd, -Y Rd, Y+q Rd, Z Rd, Z+ Rd, -Z Rd, Z+q k, Rr X, Rr X+, Rr -X, Rr Y, Rr Y+, Rr Copy Register Copy Register Pair Load Immediate Load Direct from Data Space Load Indirect Load Indirect and Post-Increment Load Indirect and Pre-Decrement Load Indirect Load Indirect and Post-Increment Load Indirect and Pre-Decrement Load Indirect with Displacement Load Indirect Load Indirect and Post-Increment Load Indirect and Pre-Decrement Load Indirect with Displacement Store Direct to Data Space Store Indirect Store Indirect and Post-Increment Store Indirect and Pre-Decrement Store Indirect Store Indirect and Post-Increment Rd Rr Rd+1:Rd Rr+1:Rr Rd K Rd (k) Rd (X) Rd (X), X X + 1 X X - 1, Rd (X) Rd (Y) Rd (Y), Y Y + 1 Y Y - 1, Rd (Y) Rd (Y + q) Rd (Z) Rd (Z), Z Z+1 Z Z - 1, Rd (Z) Rd (Z + q) Rd (k) (X) Rr (X) Rr, X X + 1 X X - 1, (X) Rr (Y) Rr (Y) Rr, Y Y + 1 None None None None None None None None None None None None None None None None None None None None None 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2
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AT94K Series FPSLIC
Instruction Set Summary (Continued)
Mnemonics ST STD ST ST ST STD LPM LPM LPM IN OUT PUSH POP Rd, Z Rd, Z+ Rd, A A, Rr Rr Rd Operands -Y, Rr Y+q, Rr Z, Rr Z+, Rr -Z, Rr Z+q, Rr Description Store Indirect and Pre-Decrement Store Indirect with Displacement Store Indirect Store Indirect and Post-Increment Store Indirect and Pre-Decrement Store Indirect with Displacement Load Program Memory Load Program Memory Load Program Memory and PostIncrement In From I/O Location Out To I/O Location Push Register on Stack Pop Register from Stack Operation Y Y - 1, (Y) Rr (Y + q) Rr (Z) Rr (Z) Rr, Z Z + 1 Z Z - 1, (Z) Rr (Z + q) Rr R0 (Z) Rd (Z) Rd (Z), Z Z + 1 Rd I/O(A) I/O(A) Rr STACK Rr Rd STACK Flags None None None None None None None None None None None None None #Clock 2 2 2 2 2 2 3 3 3 1 1 2 2
Bit and Bit-test Instructions LSL LSR ROL ROR ASR SWAP BSET BCLR SBI CBI BST BLD SEC CLC SEN CLN SEZ CLZ SEI CLI SES Rd Rd Rd Rd Rd Rd s s A, b A, b Rr, b Rd, b Logical Shift Left Logical Shift Right Rotate Left Through Carry Rotate Right Through Carry Arithmetic Shift Right Swap Nibbles Flag Set Flag Clear Set Bit in I/O Register Clear Bit in I/O Register Bit Store from Register to T Bit load from T to Register Set Carry Clear Carry Set Negative Flag Clear Negative Flag Set Zero Flag Clear Zero Flag Global Interrupt Enable Global Interrupt Disable Set Signed Test Flag Rd(n+1)Rd(n),Rd(0)0,CRd(7) Rd(n)Rd(n+1),Rd(7)0,CRd(0) Rd(0)C,Rd(n+1)Rd(n),CRd(7) Rd(7)C,Rd(n)Rd(n+1),CRd(0) Rd(n) Rd(n+1), n=0..6 Rd(3..0) Rd(7..4) SREG(s) 1 SREG(s) 0 I/O(A, b) 1 I/O(A, b) 0 T Rr(b) Rd(b) T C1 C0 N1 N0 Z1 Z0 I1 I0 S1 Z,C,N,V,H Z,C,N,V Z,C,N,V,H Z,C,N,V Z,C,N,V None SREG(s) SREG(s) None None T None C C N N Z Z I I S 1 1 1 1 1 1 1 1 2 2 1 1 1 1 1 1 1 1 1 1 1
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Instruction Set Summary (Continued)
Mnemonics CLS SEV CLV SET CLT SEH CLH NOP SLEEP WDR BREAK Operands Description Clear Signed Test Flag Set Two's Complement Overflow Clear Two's Complement Overflow Set T in SREG Clear T in SREG Set Half-carry Flag in SREG Clear Half-carry Flag in SREG No Operation Sleep Watchdog Reset Break (See specific description for Sleep) (See specific description for WDR) For on-chip debug only Operation S0 V1 V0 T1 T0 H1 H0 Flags S V V T T H H None None None None #Clock 1 1 1 1 1 1 1 1 1 1 N/A
Pin Descriptions
VCC GND PortD (PD7..PD0) Supply voltage Ground Port D is an 8-bit bi-directional I/O port with internal programmable pull-up resistors. The Port D output buffers can be programmed to sink/source either 6 or 20 mA (SCR54 - see "System Control Register - FPGA/AVR" on page 30). As inputs, Port D pins that are externally pulled Low will source current if the programmable pull-up resistors are activated. The Port D pins are input with pull-up when a reset condition becomes active, even if the clock is not running. On lower pin count packages Port D may not be available. Check the Pin List for details. PortE (PE7..PE0) Port E is an 8-bit bi-directional I/O port with internal programmable pull-up resistors. The Port E output buffers can be programmed to sink/source either 6 or 20 mA (SCR55 - see "System Control Register - FPGA/AVR" on page 30). As inputs, Port E pins that are externally pulled Low will source current if the pull-up resistors are activated. Port E also serves the functions of various special features. See Table 46 on page 149. The Port E pins are input with pull-up when a reset condition becomes active, even if the clock is not running RX0 TX0 RX1 TX1 XTAL1 Input (receive) to UART(0) - See SCR52 Output (transmit) from UART(0) - See SCR52 Input (receive) to UART(1) - See SCR53 Output (transmit) from UART(1) - See SCR53 Input to the inverting oscillator amplifier and input to the internal clock operating circuit.
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XTAL2 TOSC1 TOSC2 SCL SDA Output from the inverting oscillator amplifier Input to the inverting timer/counter oscillator amplifier Output from the inverting timer/counter oscillator amplifier 2-wire serial input/output clock 2-wire serial input/output data
Clock Options
Crystal Oscillator XTAL1 and XTAL2 are input and output, respectively, of an inverting amplifier, which can be configured for use as an on-chip oscillator, as shown in Figure 24. Either a quartz crystal or a ceramic resonator may be used. Figure 24. Oscillator Connections
MAX 1 HC BUFFER
HC
C2 C1
XTAL2 RBIAS XTAL1 GND
External Clock
To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 25. Figure 25. External Clock Drive Configuration
NC EXTERNAL OSCILLATOR SIGNAL XTAL2 XTAL1 GND
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No Clock/Oscillator Source
When not in use, for low static IDD, add a pull-down resistor to XTAL1. Figure 26. No Clock/Oscillator Connections
RPD = 4.7 K NC XTAL2 XTAL1 RPD GND
Timer Oscillator
For the timer oscillator pins, TOSC1 and TOSC2, the crystal is connected directly between the pins. The oscillator is optimized for use with a 32.768 kHz watch crystal. An external clock signal applied to this pin goes through the same amplifier having a bandwidth of 1 MHz. The external clock signal should therefore be in the range 0 Hz - 1 MHz. Figure 27. Time Oscillator Connections
C1 RB C2
RS TOSC2 TOSC1
C1 = 33 pF C2 = 27 pF RB = 10M RS = 200K
Architectural Overview
The AVR uses a Harvard architecture concept - with separate memories and buses for program and data. The program memory is accessed with a single level pipeline. While one instruction is being executed, the next instruction is pre-fetched from the program memory. This concept enables instructions to be executed in every clock-cycle. The program memory is in-system programmable SRAM memory. With a few exceptions, AVR instructions have a single 16-bit word format, meaning that every program memory address contains a single 16-bit instruction. During interrupts and subroutine calls, the return address program counter (PC) is stored on the stack. The stack is effectively allocated in the general data SRAM, as a consequence, the stack size is only limited by the total SRAM size and the usage of the SRAM. All user programs must initialize the Stack Pointer (SP) in the reset routine (before subroutines or interrupts are executed). The 16-bit stack pointer is read/write accessible in the I/O space. The data SRAM can be easily accessed through the five different addressing modes supported in the AVR architecture. A flexible interrupt module has its control registers in the I/O space with an additional global interrupt enable bit in the status register. All the different interrupts have a separate interrupt vector in the interrupt vector table at the beginning of the program memory. The different interrupts have priority in accordance with their interrupt vector position. The lower the interrupt vector address, the higher the priority. The memory spaces in the AVR architecture are all linear and regular memory maps.
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General-purpose Register File
Figure 28 shows the structure of the 32 x 8 general-purpose working registers in the CPU. Figure 28. AVR CPU General-purpose Working Registers
7 R0 R1 R2 ... R13 R14 General-purpose Working Registers R15 R16 R17 ... R26 R27 R28 R29 R30 R31 $1A $1B $1C $1D $1E $1F AVR X-register Low Byte AVR X-register High Byte AVR Y-register Low Byte AVR Y-register High Byte AVR Z-register Low Byte AVR Z-register High Byte $0D $0E $0F $10 $11 0 Addr. $00 $01 $02
All the register operating instructions in the instruction set have direct- and single-cycle access to all registers. The only exception is the five constant arithmetic and logic instructions SBCI, SUBI, CPI, ANDI and ORI between a constant and a register and the LDI instruction for loadimmediate constant data. These instructions apply to the second half of the registers in the register file - R16..R31. The general SBC, SUB, CP, AND and OR and all other operations between two registers or on a single-register apply to the entire register file. As shown in Figure 28 each register is also assigned a data memory address, mapping the registers directly into the first 32 locations of the user Data Space. Although not being physically implemented as SRAM locations, this memory organization provides great flexibility in access of the registers, as the X, Y and Z registers can be set to index any register in the file. The 4 to 16 Kbytes of data SRAM, as configured during FPSLIC download, are available for general data are implemented starting at address $0060 as follows:
4 Kbytes 8 Kbytes 12 Kbytes 16 Kbytes $0060 : $0FFF $0060 : $1FFF $0060 : $2FFF $0060 : $3FFF
Addresses beyond the maximum amount of data SRAM are unavailable for write or read and will return unknown data if accessed. Ghost memory is not implemented.
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X-register, Y-register and Z-register ALU - Arithmetic Logic Unit
Registers R26..R31 have some added functions to their general-purpose usage. These registers are address pointers for indirect addressing of the SRAM. The three indirect address registers X, Y and Z have functions as fixed displacement, automatic increment and decrement (see the descriptions for the different instructions). The high-performance AVR ALU operates in direct connection with all the 32 general-purpose working registers. Within a single clock cycle, ALU operations between registers in the register file are executed. The ALU operations are divided into three main categories - arithmetic, logical and bit-functions. The high-performance AVR Multiplier operates in direct connection with all the 32 general-purpose working registers. This unit performs 8 x 8 multipliers every two clock cycles. See multiplier details on page 106. External data SRAM (or program) cannot be used with the FPSLIC AT94K family. The five different addressing modes for the data memory cover: Direct, Indirect with Displacement, Indirect, Indirect with Pre-decrement and Indirect with Post-increment. In the register file, registers R26 to R31 feature the indirect addressing pointer registers. The Indirect with Displacement mode features a 63 address locations reach from the base address given by the Y- or Z-register. When using register indirect addressing modes with automatic Pre-decrement and Post-increment, the address registers X, Y and Z are decremented and incremented. The entire data address space including the 32 general-purpose working registers and the 64 I/O registers are all accessible through all these addressing modes. See the next section for a detailed description of the different addressing modes.
Multiplier Unit
SRAM Data Memory
Program and Data Addressing Modes
The embedded AVR core supports powerful and efficient addressing modes for access to the program memory (SRAM) and data memory (SRAM, Register File and I/O Memory). This section describes the different addressing modes supported by the AVR architecture.
Register Direct, Single-register Rd
The operand is contained in register d (Rd).
Register Direct, Two Registers Rd and Rr
Operands are contained in register r (Rr) and d (Rd). The result is stored in register d (Rd).
I/O Direct
Operand address is contained in 6 bits of the instruction word. n is the destination or source register address.
Data Direct
A 16-bit data address is contained in the 16 LSBs of a two-word instruction. Rd/Rr specify the destination or source register.
Data Indirect with Displacement
Operand address is the result of the Y- or Z-register contents added to the address contained in 6 bits of the instruction word.
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AT94K Series FPSLIC
Data Indirect
Operand address is the contents of the X-, Y- or the Z-register.
Data Indirect with Pre-decrement
The X-, Y- or the Z-register is decremented before the operation. Operand address is the decremented contents of the X, Y or the Z-register.
Data Indirect with Post-increment
The X-, Y- or the Z-register is incremented after the operation. The operand address is the content of the X-, Y- or the Z-register prior to incrementing.
Direct Program Address, JMP and CALL
Program execution continues at the address immediate in the instruction words.
Indirect Program Addressing, IJMP and ICALL
Program execution continues at address contained by the Z-register (i.e., the PC is loaded with the contents of the Z-register).
Relative Program Addressing, RJMP and RCALL
Program execution continues at address PC + k + 1. The relative address k is -2048 to 2047. Memory Access Times and Instruction Execution Timing This section describes the general access timing concepts for instruction execution and internal memory access. The AVR CPU is driven by the XTAL1 input directly generated from the external clock crystal for the chip. No internal clock division is used. Figure 29 shows the parallel instruction fetches and instruction executions enabled by the Harvard architecture and the fast-access register file concept. This is the basic pipelining concept to obtain up to 1 MIPS per MHz with the corresponding unique results for functions per cost, functions per clocks and functions per power-unit.
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Figure 29. The Parallel Instruction Fetches and Instruction Executions
T1 T2 T3 T4
AVR CLK 1st Instruction Fetch 1st Instruction Execute 2nd Instruction Fetch 2nd Instruction Execute 3rd Instruction Fetch 3rd Instruction Execute 4th Instruction Fetch
Figure 30 shows the internal timing concept for the register file. In a single clock cycle an ALU operation using two register operands is executed, and the result is stored back to the destination register. Figure 30. Single Cycle ALU Operation
T1 T2 T3 T4
AVR CLK Total ExecutionTime Register Operands Fetch ALU Operation Execute Result Write Back
The internal data SRAM access is performed in two system clock cycles as described in Figure 31. Figure 31. On-chip Data SRAM Access Cycles
T1 T2 T3 T4
AVR CLK Address Data WR Data RD
Prev. Address Address
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Read
Write
AT94K Series FPSLIC
Memory-mapped I/O
The I/O space definition of the embedded AVR core is shown in the following table: AT94K Register Summary
Address $3F ($5F) $3E ($5E) $3D ($5D) $3C ($5C) $3B ($5B) $3A ($5A) $39 ($59) $38 ($58) $37 ($57) $36 ($56) $35 ($55) $34 ($54) $33 ($53) $32 ($52) $31 ($51) $30 ($50) $2F ($4F) $2E ($4E) $2D ($4D) $2C ($4C) $2B ($4B) $2A ($4A) $29 ($49) $28 ($48) $27 ($47) $26 ($46) $25 ($45) $24 ($44) $23 ($43) $22 ($42) $21 ($41) $20 ($40) $1F ($3F) $1E ($3E) $1D ($3D) $1C ($3C) $1B ($3B) $1A ($3A) $19 ($39) $18 ($38) $17 ($37) Name SREG SPH SPL Reserved EIMF SFTCR TIMSK TIFR Reserved TWCR MCUR Reserved TCCR0 TCNT0 OCR0 SFIOR TCCR1A TCCR1B TCNT1H TCNT1L OCR1AH OCR1AL OCR1BH OCR1BL TCCR2 ASSR ICR1H ICR1L TCNT2 OCR2 WDTCR UBRRHI TWDR TWAR TWSR TWBR FPGAD FPGAZ FPGAY FPGAX FISUD UART1 Baud Rate High Nibble [11..8] 2-wire Serial Data Register 2-wire Serial Address Register 2-wire Serial Status Register 2-wire Serial Bit Rate Register FPGA Cache Data Register (D7 - D0) FPGA Cache Z Address Register (T3 - T0) (Z3 - Z0) FPGA Cache Y Address Register (Y7 - Y0) FPGA Cache X Address Register (X7 - X0) FPGA I/O Select, Interrupt Mask/Flag Register D (Reserved on AT94K05) Timer/Counter1 - Input Capture Register High Byte Timer/Counter1 - Input Capture Register Low Byte Timer/Counter2 (8-bit) Timer/Counter 2 Output Compare Register WDTOE WDE WDP2 WDP1 WDP0 COM1A1 ICNC1 COM1A0 ICES1 COM1B1 ICPE COM1B0 FOC1A CTC1 FOC1B CS12 FOC0 PWM0 COM01 COM00 CTC0 CS02 CS01 CS00 69 70 71 PSR2 PWM11 CS11 PSR10 PWM10 CS10 66 76 77 78 78 79 79 79 79 COM20 CTC2 AS2 CS22 TCN20B CS21 OCR2UB CS20 TCR2UB 69 73 80 80 70 71 83 105 111 112 112 109 52 53 53 53 54, 56 TWINT JTRF TWEA JTD TWSTA SE TWSTO SM1 TWWC SM0 TWEN PORF WDRF TWIE EXTRF 110 51 TOIE1 TOV1 OCIE1A OCF1A OCIE1B OCF1B TOIE2 TOV2 INTF3 INTF2 INTF1 INTF0 INT3 FMXOR TICIE1 ICF1 INT2 WDTS OCIE2 OCF2 INT1 DBG TOIE0 TOV0 INT0 SRST OCIE0 OCF0 62 51 62 63 Bit 7 I SP15 SP7 Bit 6 T SP14 SP6 Bit 5 H SP13 SP5 Bit 4 S SP12 SP4 Bit 3 V SP11 SP3 Bit 2 N SP10 SP2 Bit 1 Z SP9 SP1 Bit 0 C SP8 SP0 Reference Page 51 57 51
Timer/Counter0 (8-bit) Timer/Counter0 Output Compare Register
Timer/Counter1 - Counter Register High Byte Timer/Counter1 - Counter Register Low Byte Timer/Counter1 - Output Compare Register A High Byte Timer/Counter1 - Output Compare Register A Low Byte Timer/Counter1 - Output Compare Register B High Byte Timer/Counter1 - Output Compare Register B Low Byte FOC2 PWM2 COM21
UART0 Baud Rate Low Nibble [11..8]
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AT94K Register Summary (Continued)
Address $16 ($36) $15 ($35) $14 ($34) $13 ($33) $12 ($32) $11 ($31) $10 ($30) $0F ($2F) $0E ($2E) $0D ($2D) $0C ($2C) $0B ($2B) $0A ($2A) $09 ($29) $08 ($28) $07 ($27) $06 ($26) $05 ($25) $04 ($24) $03 ($23) $02 ($22) $01 ($21) $00 ($20) Name FISUC FISUB FISUA FISCR PORTD DDRD PIND Reserved Reserved Reserved UDR0 UCSR0A UCSR0B UBRR0 OCDR (Reserved) PORTE DDRE PINE Reserved UDR1 UCSR1A UCSR1B UBRR1 UART1 I/O Data Register RXC1 RXCIE1 TXC1 TXCIE1 UDRE1 UDRIE1 FE1 RXEN1 OR1 TXEN1 CHR91 U2X1 RXB81 MPCM1 TXB81 101 101 103 105 UART0 I/O Data Register RXC0 RXCIE0 TXC0 TXCIE0 UDRE0 UDRIE0 FE0 RXEN0 OR0 TXEN0 CHR90 U2X0 RXB80 MPCM0 TXB80 101 101 103 105 Reserved(1) PORTE6 DDRE6 PINE6 PORTE5 DDRE5 PINE5 PORTE4 DDRE4 PINE4 PORTE3 DDRE3 PINE3 PORTE2 DDRE2 PINE2 PORTE1 DDRE1 PINE1 PORTE0 DDRE0 PINE0 126 126 126 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Reference Page 54, 56 54, 56 54, 56 XFIS1 PORTD6 DDRD6 PIND6 PORTD5 DDRD5 PIND5 PORTD4 DDRD4 PIND4 PORTD3 DDRD3 PIND3 PORTD2 DDRD2 PIND2 PORTD1 DDRD1 PIND1 XFIS0 PORTD0 DDRD0 PIND0 53 124 124 124
FPGA I/O Select, Interrupt Mask/Flag Register C (Reserved on AT94K05) FPGA I/O Select, Interrupt Mask/Flag Register B FPGA I/O Select, Interrupt Mask/Flag Register A FIADR PORTD7 DDRD7 PIND7
UART0 Baud-rate Register IDRD PORTE7 DDRE7 PINE7
UART1 Baud-rate Register
Note:
1. The On-chip Debug Register (OCDR) is detailed on the "FPSLIC On-chip Debug System" distributed within Atmel and select third-party vendors only under Non-Disclosure Agreement (NDA). Contact fpslic@atmel.com for a copy of this document.
The embedded AVR core I/Os and peripherals, and all the virtual FPGA peripherals are placed in the I/O space. The different I/O locations are directly accessed by the IN and OUT instructions transferring data between the 32 x 8 generalpurpose working registers and the I/O space. I/O registers within the address range $00 - $1F are directly bit-accessible using the SBI and CBI instructions. In these registers, the value of single bits can be checked by using the SBIS and SBIC instructions. When using the I/O specific instructions IN, OUT, the I/O register address $00 - $3F are used, see Figure 32. When addressing I/O registers as SRAM, $20 must be added to this address. All I/O register addresses throughout this document are shown with the SRAM address in parentheses.
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Figure 32. Memory-mapped I/O
SRAM Space $5F
I/O Space $3F
Memory-mapped I/O
$1F Registers r0 - r31 $00 Used for In/Out Instructions Used for all Other Instructions $00
For single-cycle access (In/Out Commands) to I/O, the instruction has to be less than 16 bits:
opcode 5 bits register r0 - 31 ($1F) 5 bits address r0 - 63 ($3F) 6 bits
In the data SRAM, the registers are located at memory addresses $00 - $1F and the I/O space is located at memory addresses $20 - $5F. As there are only 6 bits available to refer to the I/O space, the address is shifted down 2 bits. This means the In/Out commands access $00 to $3F which goes directly to the I/O and maps to $20 to $5F in SRAM. All other instructions access the I/O space through the $20 - $5F addressing. For compatibility with future devices, reserved bits should be written zero if accessed. Reserved I/O memory addresses should never be written. The status flags are cleared by writing a logic 1 to them. Note that the CBI and SBI instructions will operate on all bits in the I/O register, writing a one back into any flag read as set, thus clearing the flag. The CBI and SBI instructions work with registers $00 to $1F only.
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Status Register - SREG
The AVR status register(1) - SREG - at I/O space location $3F ($5F) is defined as:
Bit $3F ($5F) Read/Write Initial Value 7 I R/W 0 6 T R/W 0 5 H R/W 0 4 S R/W 0 3 V R/W 0 2 N R/W 0 1 Z R/W 0 0 C R/W 0 SREG
Note:
1. Note that the status register is not automatically stored when entering an interrupt routine and restored when returning from an interrupt routine. This must be handled by software.
* Bit 7 - I: Global Interrupt Enable The global interrupt enable bit must be set (one) for the interrupts to be enabled. The individual interrupt enable control is then performed in separate control registers. If the global interrupt enable register is cleared (zero), none of the interrupts are enabled independent of the individual interrupt enable settings. The I-bit is cleared by the hardware after an interrupt has occurred, and is set by the RETI instruction to enable subsequent interrupts. * Bit 6 - T: Bit Copy Storage The bit copy instructions BLD (Bit LoaD) and BST (Bit STore) use the T-bit as source and destination for the operated bit. A bit from a register in the register file can be copied into T by the BST instruction, and a bit in T can be copied into a bit in a register in the register file by the BLD instruction. * Bit 5 - H: Half-carry Flag The half-carry flag H indicates a half-carry in some arithmetic operations. * Bit 4 - S: Sign Bit, S = N V The S-bit is always an exclusive or between the negative flag N and the two's complement overflow flag V. * Bit 3 - V: Two's Complement Overflow Flag The two's complement overflow flag V supports two's complement arithmetics. * Bit 2 - N: Negative Flag The negative flag N indicates a negative result from an arithmetical or logical operation. * Bit 1 - Z: Zero Flag The zero flag Z indicates a zero result from an arithmetical or logical operation. * Bit 0 - C: Carry Flag The carry flag C indicates a carry in an arithmetical or logical operation.
Stack Pointer - SP
The general AVR 16-bit Stack Pointer is effectively built up of two 8-bit registers in the I/O space locations $3E ($5E) and $3D ($5D). Future versions of FPSLIC may support up to 64K Bytes of memory; therefore, all 16 bits are used.
Bit $3E ($5E) $3D ($5D) Read/Write Initial Value 15 SP15 SP7 7 R/W R/W 0 0 14 SP14 SP6 6 R/W R/W 0 0 13 SP13 SP5 5 R/W R/W 0 0 12 SP12 SP4 4 R/W R/W 0 0 11 SP11 SP3 3 R/W R/W 0 0 10 SP10 SP2 2 R/W R/W 0 0 9 SP9 SP1 1 R/W R/W 0 0 8 SP8 SP0 0 R/W R/W 0 0 SPH SPL
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AT94K Series FPSLIC
The Stack Pointer points to the data SRAM stack area where the Subroutine and Interrupt Stacks are located. This Stack space in the data SRAM must be defined by the program before any subroutine calls are executed or interrupts are enabled. The stack pointer must be set to point above $60. The Stack Pointer is decremented by one when data is pushed onto the Stack with the PUSH instruction, and it is decremented by two when an address is pushed onto the Stack with subroutine calls and interrupts. The Stack Pointer is incremented by one when data is popped from the Stack with the POP instruction, and it is incremented by two when an address is popped from the Stack with return from subroutine RET or return from interrupt RETI.
Software Control of System Configuration
The software control register will allow the software to manage select system level configuration bits.
Software Control Register - SFTCR
Bit $3A ($5A) Read/Write Initial Value 7 R 0 6 R 0 5 R 0 4 R 0 3 FMXOR R/W 0 2 WDTS R/W 0 1 DBG R/W 0 0 SRST R/W 0 SFTCR
* Bits 7..4 - Res: Reserved Bits These bits are reserved in the AT94K and always read as zero. * Bit 3 - FMXOR: Frame Mode XOR (Enable/Disable) This bit is XORed with the System Control Register's Enable Frame Interface bit. The behavior when this bit is set to 1 is dependent on how the SCR was initialized. If the Enable Frame Interface bit in the SCR is 0, the FMXOR bit enables the Frame Interface when set to 1. If the Enable Frame Interface bit in the SCR is 1, the FMXOR bit disables the Frame Interface when set to 1. During AVR reset, the FMXOR bit is cleared by the hardware. * Bit 2 - WDTS: Software Watchdog Test Clock Select When this bit is set to 1, the test clock signal is selected to replace the AVR internal oscillator into the associated watchdog timer logic. During AVR reset, the WDTS bit is cleared by the hardware. * Bit 1 - DBG: Debug Mode When this bit is set to 1, the AVR can write its own program SRAM. During AVR reset, the DBG bit is cleared by the hardware. * Bit 0 - SRST: Software Reset When this bit is set (one), a reset request is sent to the system configuration external to the AVR. Appropriate reset signals are generated back into the AVR and configuration download is initiated. A software reset will cause the EXTRF bit in the MCUR register to be set (one), which remains set throughout the AVR reset and may be read by the restarted program upon reset complete. The external reset flag is set (one) since the requested reset is issued from the system configuration external to the AVR core. During AVR reset, the SRST bit is cleared by the hardware.
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MCU Control Status/Register - MCUR
The MCU Register contains control bits for general MCU functions and status bits to indicate the source of an MCU reset.
Bit $35 ($55) Read/Write Initial Value 7 JTRF R/W 0 6 JTD R/W 0 5 SE R/W 0 4 SM1 R/W 0 3 SM0 R/W 0 2 PORF R/W 1 1 WDRF R/W 0 0 EXTRF R/W 1 MCUR
* Bit 7 - JTRF: JTAG Reset Flag This flag is set (one) upon issuing the AVR_RESET ($C) JTAG instruction. The flag can only be cleared (zero) by writing a zero to the JTRF bit or by a power-on reset. The bit will not be cleared by hardware during AVR reset. * Bit 6 - JTD: JTAG Disable When this bit is cleared (zero), and the System Control Register JTAG Enable bit is set (one), the JTAG interface is disabled. To avoid unintentional disabling or enabling of the JTAG interface, a timed sequence must be followed when changing this bit: the application software must write this bit to the desired value twice within four cycles to change its value. * Bit 5 - SE: Sleep Enable The SE bit must be set (one) to make the MCU enter the Sleep mode when the SLEEP instruction is executed. To avoid the MCU entering the Sleep mode unless it is the programmers purpose, it is recommended to set the Sleep Enable SE bit just before the execution of the SLEEP instruction. * Bits 4, 3 - SM1/SM0: Sleep Mode Select Bits 1 and 0 This bit selects between the three available Sleep modes as shown in Table 11. * Bit 2 - PORF: Power-on Reset Flag This flag is set (one) upon power-up of the device. The flag can only be cleared (zero) by writing a zero to the PORF bit. The bit will not be cleared by the hardware during AVR reset. * Bit 1 - WDRF: Watchdog Reset Flag This bit is set if a watchdog reset occurs. The bit is cleared by writing a logic 0 to the flag. * Bit 0 - EXTRF: External (Software) Reset Flag This flag is set (one) in three separate circumstances: power-on reset, use of Resetn/AVRResetn and writing a one to the SRST bit in the Software Control Register - SFTCR. The PORF flag can be checked to eliminate power-on reset as a cause for this flag to be set. There is no way to differentiate between use of Resetn/AVRResetn and software reset. The flag can only be cleared (zero) by writing a zero to the EXTRF bit. The bit will not be cleared by the hardware during AVR reset. Table 11. Sleep Mode Select
SM1 0 0 1 1 SM0 0 1 0 1 Sleep Mode Idle Reserved Power-down Power-save
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FPGA Cache Logic
FPGA Cache Data Register - FPGAD
Bit $1B ($3B) Read/Write Initial Value 7 MSB W N/A W N/A W N/A W N/A W N/A W N/A W N/A 6 5 4 3 2 1 0 LSB W N/A FPGAD
The FPGAD I/O Register address is not supported by a physical register; it is simply the I/O address that, if written to, generates the FPGA Cache I/O write strobe. The CACHEIOWE signal is a qualified version of the AVR IOWE signal. It will only be active if an OUT or ST (store to) instruction references the FPGAD I/O address. The FPGAD I/O address is write-sensitiveonly; an I/O read to this location is ignored. If the AVR Cache Interface bit in the SCR [BIT62] is set (one), the data being "written" to this address is cached to the FPGA address specified by the FPGAX..Z registers (see below) during the active CACHEIOWE strobe.
FPGA Cache Z Address Registers - FPGAX..Z
Bit $18 ($38) $19 ($39) $1A ($3A) Read/Write Initial Value 7 FCX7 FCY7 FCT3 R/W 0 6 FCX6 FCY6 FCT2 R/W 0 5 FCX5 FCY5 FCT1 R/W 0 4 FCX4 FCY4 FCT0 R/W 0 3 FCX3 FCY3 FCZ3 R/W 0 2 FCX2 FCY2 FCZ2 R/W 0 1 FCX1 FCY1 FCZ1 R/W 0 0 FCX0 FCY0 FCZ0 R/W 0
FPGAX FPGAY FPGAZ
The three FPGA Cache address registers combine to form the 24-bit address, CACHEADDR[23:0], delivered to the FPGA cache logic outside the AVR block during a write to the FPGAD I/O Register (see above).
FPGA I/O Selection by AVR
Sixteen select signals are sent to the FPGA for I/O addressing. These signals are decoded from four I/O registry addresses (FISUA...D) and extended to sixteen with two bits from the FPGA I/O Select Control Register (FISCR). In addition, the FPGAIORE and FPGAIOWE signals are qualified versions of the IORE and IOWE signals. Each will only be active if one of the four base I/O addresses are referenced. It is necessary for the FPGA design to implement any required registers for each select line; each qualified with either the FPGAIORE or FPGAIOWE strobe. Refer to the FPGA/AVR Interface section for more details. Only the FISCR registers physically exist. The FISUA...D I/O addresses for the purpose of FPGA I/O selection are NOT supported by AVR Core I/O space registers; they are simply I/O addresses (available to 1 cycle IN/OUT instructions) which trigger appropriate enabling of the FPGA select lines and the FPGA IORE/IOWE strobes (see Figure 18 on page 21).
FPGA I/O Select Control Register - FISCR
Bit $13 ($33) Read/Write Initial Value 7 FIADR R/W 0 6 R 0 5 R 0 4 R 0 3 R 0 2 R 0 1 XFIS1 R/W 0 0 XFIS0 R/W 0 FISCR
* Bit 7 - FIADR: FPGA Interrupt Addressing Enable When FIADR is set (one), the four dual-purpose I/O addresses, FISUA..D, are mapped to four physical registers that provide memory space for FPGA interrupt masking and interrupt flag status. When FIADR is cleared (zero), and I/O read or write to one of the four dual-purpose I/O addresses, FISUA..D, will access its associated group of four FPGA I/O select lines. The XFIS1 and XFIS0 bits (see Table 12) further determine which one select line in the accessed group is set (one). A read will assign the FPGA I/O read enable to the AVR I/O read enable (FPGAIORE IORE) and a write, the FPGA I/O write enable to the AVR I/O write enable 53
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(FPGAIOWE IOWE). FPGA macros utilizing one or more FPGA I/O select lines must use the FPGA I/O read/write enables, FPGAIORE or FPGAIOWE, to qualify each select line. The FIADR bit will be cleared (zero) during AVR reset. * Bits 6..2 - Res: Reserved Bits These bits are reserved and always read as zero. * Bits 1, 0 - XFIS1, 0: Extended FPGA I/O Select Bits 1, 0 XFIS[1:0] determines which one of the four FPGA I/O select lines will be set (one) within the accessed group. An I/O read or write to one of the four dual-purpose I/O addresses, FISUA..D, will access one of four groups. Table 12 details the FPGA I/O selection scheme. Table 12. FPGA I/O Select Line Scheme
Read or Write I/O Address FISCR Register XFIS1 0 0 FISUA $14 ($34) 1 1 0 0 FISUB $15 ($35) 1 1 0 FISUC $16 ($36)(1) 0 1 1 0 FISUD $17 ($37)(1) 0 1 1 Note: 1. Not available on AT94K05. 0 1 0 1 0 1 0 1 0 1 0000 0000 0000 0000 0000 0000 0001 0010 0100 1000 0000 0000 0001 0010 0100 1000 0000 0000 0000 0000 0100 1000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0 1 0 1 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001 0010 0100 1000 0000 0000 XFIS0 0 1 15..12 0000 0000 FPGA I/O Select Lines 11..8 0000 0000 7..4 0000 0000 3..0 0001 0010
In summary, 16 select signals are sent to the FPGA for I/O addressing. These signals are decoded from four base I/O Register addresses (FISUA..D) and extended to 16 with two bits from the FPGA I/O Select Control Register, XFIS1 and XFIS0. The FPGA I/O read and write signals, FPGAIORE and FPGAIOWE, are qualified versions of the AVR IORE and IOWE signals. Each will only be active if one of the four base I/O addresses is accessed. Reset: all select lines become active and an FPGAIOWE strobe is enabled. This is to allow the FPGA design to load zeros (8'h00) from the D-bus into appropriate registers.
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AT94K Series FPSLIC
General AVR/FPGA I/O Select Procedure I/O select depends on the FISCR register setup and the FISUA..D register written to or read from. The following FISCR setups and writing data to the FISUA..D registers will result in the shown I/O select lines and data presented on the 8-bit AVR-FPGA data bus. Table 13. FISCR Register Setups and I/O Select Lines.
FISCR Register
FIADR(b7)
0 0 0 0
I/O Select Lines(1)
XFIS0(b0)
0 1 0 1 FISUA IOSEL 0 IOSEL 1 IOSEL 2 IOSEL 3 FISUB IOSEL 4 IOSEL 5 IOSEL 6 IOSEL 7 FISUC IOSEL 8 IOSEL 9 IOSEL 10 IOSEL 11 FISUD IOSEL 12 IOSEL 13 IOSEL 14 IOSEL 15
b6-2
-
XFIS1(b1)
0 0 1 1
Note:
1. IOSEL 15..8 are not available on AT94K05.
;--------------------------------------------io_select0_write: ldi r16,0x00 out FISCR,r16 out FISUA,r17; ;FIADR=0,XFIS1=0,XFIS0=0 ->I/O select line=0 ;load I/O select values into FISCR register ;select line 0 high. Place data on AVR<->FPGA bus ; from r17 register. (out going data is assumed ; to be present in r17 before calling this subroutine) ret ;--------------------------------------------io_select13_read: ldi r16,0x01 out FISCR,r16 in r18,FISUD ret ;FIADR=0,XFIS1=0,XFIS0=1 ->I/O select line=13 ;load I/O select values into FISCR register ;select line 13 high. Read data on AVR<->FPGA bus ;which was placed into register FISUD.
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Figure 33. Out Instruction - AVR Writing to the FPGA
AVR INST AVR CLOCK AVR IOWE AVR IOADR
(FISUA, B, C or D)
OUT INSTRUCTION
AVR DBUS
(FPGA DATA IN)
WRITE DATA VALID
FPGA IOWE FPGA I/O SELECT "n" FPGA CLOCK
(SET TO AVR SYSTEM CLOCK) (1)
Note:
1. AVR expects Write to be captured by the FPGA upon posedge of the AVR clock.
Figure 34. In Instruction - AVR Reading FPGA
AVR INST AVR CLOCK
IN INSTRUCTION
(1) (2)
AVR IORE
(2)
AVR IOADR
(FISUA, B, C or D)
AVR DBUS
(FPGA DATA OUT)
READ DATA VALID
FPGA IORE FPGA I/O SELECT "n"
Notes: 1. AVR captures read data upon posedge of the AVR clock. 2. At the end of an FPGA read cycle, there is a chance for the AVR data bus contention between the FPGA and another peripheral to start to drive (active IORE at new address versus FPGAIORE + Select "n"), but since the AVR clock would have already captured the data from AVR DBUS (= FPGA Data Out), this is a "don't care" situation.
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AT94K Series FPSLIC
FPGA I/O Interrupt Control by AVR
This is an alternate memory space for the FPGA I/O Select addresses. If the FIADR bit in the FISCR register is set to logic 1, the four I/O addresses, FISUA - FISUD, are mapped to physical registers and provide memory space for FPGA interrupt masking and interrupt flag status. If the FIADR bit in the FISCR register is cleared to a logic 0, the I/O register addresses will be decoded into FPGA select lines. All FPGA interrupt lines into the AVR are negative edge triggered. See page 58 for interrupt priority.
Interrupt Control Registers - FISUA..D
Bit $14 ($34) $15 ($35) $16 ($36) $17 ($37) Read/Write Initial Value 7 FIF3 FIF7 FIF11 FIF15 R/W 0 6 FIF2 FIF6 FIF10 FIF14 R/W 0 5 FIF1 FIF5 FIF9 FIF13 R/W 0 4 FIF0 FIF4 FIF8 FIF12 R/W 0 3 FINT3 FINT7 FINT11 FINT15 R/W 0 2 FINT2 FINT6 FINT10 FINT14 R/W 0 1 FINT1 FINT5 FINT9 FINT13 R/W 0 0 FINT0 FINT4 FINT8 FINT12 R/W 0 FISUA FSUB FISUC FISUD
* Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0 The 16 FPGA interrupt flag bits all work the same. Each is set (one) by a valid negative edge transition on its associated interrupt line from the FPGA. Valid transitions are defined as any change in state preceded by at least two cycles of the old state and succeeded by at least two cycles of the new state. Therefore, it is required that interrupt lines transition from 1 to 0 at least two cycles after the line is stable High; the line must then remain stable Low for at least two cycles following the transition. Each bit is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, each bit will be cleared by writing a logic 1 to it. When the I-bit in the Status Register, the corresponding FPGA interrupt mask bit and the given FPGA interrupt flag bit are set (one), the associated interrupt is executed. * Bits 7..4 - FIF7 - 4: FPGA Interrupt Flags 7 - 4 See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0. * Bits 7..4 - FIF11 - 8: FPGA Interrupt Flags 11 - 8 See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0. Not available on the AT94K05. * Bits 7..4 - FIF15 - 12: FPGA Interrupt Flags 15 - 12 See Bits 7..4 - FIF3 - 0: FPGA Interrupt Flags 3 - 0. Not available on the AT94K05. * Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0(1) The 16 FPGA interrupt mask bits all work the same. When a mask bit is set (one) and the I-bit in the Status Register is set (one), the given FPGA interrupt is enabled. The corresponding interrupt handling vector is executed when the given FPGA interrupt flag bit is set (one) by a negative edge transition on the associated interrupt line from the FPGA.
Note: 1. FPGA interrupts 3 - 0 will cause a wake-up from the AVR Sleep modes. These interrupts are treated as low-level triggered in the Power-down and Power-save modes, see "Sleep Modes" on page 66.
* Bits 3..0 - FINT7 - 4: FPGA Interrupt Masks 7 - 4 See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0. * Bits 3..0 - FINT11 - 8: FPGA Interrupt Masks 11 - 8 See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0. Not available on the AT94K05. * Bits 3..0 - FINT15 - 12: FPGA Interrupt Masks 15 -12 See Bits 3..0 - FINT3 - 0: FPGA Interrupt Masks 3 - 0. Not available on the AT94K05.
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Reset and Interrupt Handling
The embedded AVR and FPGA core provide 35 different interrupt sources. These interrupts and the separate reset vector each have a separate program vector in the program memory space. All interrupts are assigned individual enable bits (masks) which must be set (one) together with the I-bit in the status register in order to enable the interrupt. The lowest addresses in the program memory space must be defined as the Reset and Interrupt vectors. The complete list of vectors is shown in Table 14. The list also determines the priority levels of the different interrupts. The lower the address the higher the priority level. RESET has the highest priority, and next is FPGA_INT0 - the FPGA Interrupt Request 0 etc. Table 14. Reset and Interrupt Vectors
Vector No. (hex) 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 10 11 12 13 14 15 16 Program Address $0000 $0002 $0004 $0006 $0008 $000A $000C $000E $0010 $0012 $0014 $0016 $0018 $001A $001C $001E $0020 $0022 $0024 $0026 $0028 $002A Source RESET FPGA_INT0 EXT_INT0 FPGA_INT1 EXT_INT1 FPGA_INT2 EXT_INT2 FPGA_INT3 EXT_INT3 TIM2_COMP TIM2_OVF TIM1_CAPT TIM1_COMPA TIM1_COMPB TIM1_OVF TIM0_COMP TIM0_OVF FPGA_INT4 FPGA_INT5 FPGA_INT6 FPGA_INT7 UART0_RXC Interrupt Definition Reset Handle: Program Execution Starts Here FPGA Interrupt0 Handle External Interrupt0 Handle FPGA Interrupt1 Handle External Interrupt1 Handle FPGA Interrupt2 Handle External Interrupt2 Handle FPGA Interrupt3 Handle External Interrupt3 Handle Timer/Counter2 Compare Match Interrupt Handle Timer/Counter2 Overflow Interrupt Handle Timer/Counter1 Capture Event Interrupt Handle Timer/Counter1 Compare Match A Interrupt Handle Timer/Counter1 Compare Match B Interrupt Handle Timer/Counter1 Overflow Interrupt Handle Timer/Counter0 Compare Match Interrupt Handle Timer/Counter0 Overflow Interrupt Handle FPGA Interrupt4 Handle FPGA Interrupt5 Handle FPGA Interrupt6 Handle FPGA Interrupt7 Handle UART0 Receive Complete Interrupt Handle
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Table 14. Reset and Interrupt Vectors (Continued)
Vector No. (hex) 17 18 19 1A 1B 1C 1D 1E 1F 20 21 22 23 24 Program Address $002C $002E $0030 $0032 $0034 $0036 $0038 $003A $003C $003E $0040 $0042 $0044 $0046 Source UART0_DRE UART0_TXC FPGA_INT8 FPGA_INT9 FPGA_INT10 FPGA_INT11 UART1_RXC UART1_DRE UART1_TXC FPGA_INT12 FPGA_INT13 FPGA_INT14 FPGA_INT15 TWS_INT Interrupt Definition UART0 Data Register Empty Interrupt Handle UART0 Transmit Complete Interrupt Handle FPGA Interrupt8 Handle (not available on AT94K05) FPGA Interrupt9 Handle (not available on AT94K05) FPGA Interrupt10 Handle (not available on AT94K05) FPGA Interrupt11 Handle (not available on AT94K05) UART1 Receive Complete Interrupt Handle UART1 Data Register Empty Interrupt Handle UART1 Transmit Complete Interrupt Handle FPGA Interrupt12 Handle (not available on AT94K05) FPGA Interrupt13 Handle (not available on AT94K05) FPGA Interrupt14 Handle (Not Available on AT94K05) FPGA Interrupt15 Handle (not available on AT94K05) 2-wire Serial Interrupt
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The most typical program setup for the Reset and Interrupt Vector Addresses are:
Address $0000 $0002 $0004 $0006 $0008 $000A $000C $000E $0010 $0012 $0014 $0016 $0018 $001A $001C $001E $0020 $0022 $0024 $0026 $0028 $002A $002C $002E $0030 $0032 $0034 $0036 $0038 $003A $003C $003E $0040 $0042 $0044 $0046 ; RESET: $0048 $0049 $004A $004B $004C ... ldi out ldi out ... r16,high(RAMEND) SPH,r16 r16,low(RAMEND) SPL,r16 xxx ... ; Main program start Labels jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp jmp Code RESET FPGA_INT0 EXT_INT0 FPGA_INT1 EXT_INT1 FPGA_INT2 EXT_INT2 FPGA_INT3 EXT_INT3 TIM2_COMP TIM2_OVF TIM1_CAPT TIM1_COMPA TIM1_COMPB TIM1_OVF TIM0_COMP TIM0_OVF FPGA_INT4 FPGA_INT5 FPGA_INT6 FPGA_INT7 UART0_RXC UART0_DRE UART0_TXC FPGA_INT8 FPGA_INT9 FPGA_INT10 FPGA_INT11 UART1_RXC UART1_DRE UART1_TXC FPGA_INT12 FPGA_INT13 FPGA_INT14 FPGA_INT15 TWS_INT Comments Reset Handle: Program Execution Starts Here ; FPGA Interrupt0 Handle ; External Interrupt0 Handle ; FPGA Interrupt1 Handle ; External Interrupt1 Handle ; FPGA Interrupt2 Handle ; External Interrupt2 Handle ; FPGA Interrupt3 Handle ; External Interrupt3 Handle ; Timer/Counter2 Compare Match Interrupt Handle ; Timer/Counter2 Overflow Interrupt Handle ; Timer/Counter1 Capture Event Interrupt Handle
; Timer/Counter1 Compare Match A Interrupt Handle ; Timer/Counter1 Compare Match B Interrupt Handle
; Timer/Counter1 Overflow Interrupt Handle
; Timer/Counter0 Compare Match Interrupt Handle
; Timer/Counter0 Overflow Interrupt Handle ; FPGA Interrupt4 Handle ; FPGA Interrupt5 Handle ; FPGA Interrupt6 Handle ; FPGA Interrupt7 Handle ; UART0 Receive Complete Interrupt Handle ; UART0 Data Register Empty Interrupt Handle ; UART0 Transmit Complete Interrupt Handle ; FPGA Interrupt8 Handle(1) ; FPGA Interrupt9 Handle(1) ; FPGA Interrupt10 Handle(1) ; FPGA Interrupt11 Handle(1) ; UART1 Receive Complete Interrupt Handle ; UART1 Data Register Empty Interrupt Handle ; UART1 Transmit Complete Interrupt Handle ; FPGA Interrupt12 Handle(1) ; FPGA Interrupt13 Handle(1) ; FPGA Interrupt14 Handle(1) ; FPGA Interrupt15 Handle(1) ; 2-wire Serial Interrupt
Note:
1. Not Available on AT94K05. However, the vector jump table positions must be maintained for appropriate UART and 2-wire serial interrupt jumps.
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Reset Sources The embedded AVR core has five sources of reset: * * * * * External Reset. The MCU is reset immediately when a low-level is present on the RESET or AVR RESET pin. Power-on Reset. The MCU is reset upon chip power-up and remains in reset until the FPGA configuration has entered Idle mode. Watchdog Reset. The MCU is reset when the Watchdog Timer period expires and the watchdog is enabled. Software Reset. The MCU is reset when the SRST bit in the Software Control register is set (one). JTAG AVR Reset. The MCU is reset as long as there is a logic one in the Reset Register, one of the scan chains of the JTAG system. See "IEEE 1149.1 (JTAG) Boundary-scan" on page 73.
During reset, all I/O registers except the MCU Status register are then set to their Initial Values, and the program starts execution from address $0000. The instruction placed in address $0000 must be a JMP - absolute jump instruction to the reset handling routine. If the program never enables an interrupt source, the interrupt vectors are not used, and regular program code can be placed at these locations. The circuit diagram in Figure 35 shows the reset logic. Table 15 defines the timing and electrical parameters of the reset circuitry. Figure 35. Reset Logic
DATA BUS
POR
MCU STATUS
EXTRF
PORF
WDRF
SFTCR BIT 0 WATCHDOG TIMER JTAG RESET REGISTER
COUNTER RESET
RESET/ AVR RESET
FPGA CONFIG LOGIC
JT RF
S
Q
INTERNAL RESET
FULL R INTERNAL OSCILLATOR DELAY COUNTERS SYSTEM CLOCK
SEL [4:0] CONTROLLED BY FPGA CONFIGURATION
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Table 15. Reset Characteristics (VCC = 3.3V)
Symbol Parameter Power-on Reset Threshold (Rising) VPOT(1) Power-on Reset Threshold (Falling) RESET Pin Threshold Voltage Minimum 1.0 0.4 Typical 1.4 0.6 VCC/2 5 TTOUT Reset Delay Time-out Period 0.4 3.2 12.8 0.5 4.0 16.0 0.6 4.8 19.2 Maximum 1.8 0.8 Units V V V CPU cycles ms
VRST
Note:
1. The Power-on Reset will not work unless the supply voltage has been below VPOT (falling).
Power-on Reset
A Power-on Reset (POR) circuit ensures that the device is reset from power-on. As shown in Figure 35, an internal timer clocked from the Watchdog Timer oscillator prevents the MCU from starting until after a certain period after VCC has reached the Power-on Threshold voltage - VPOT, regardless of the VCC rise time (see Figure 36 and Figure 37). Figure 36. MCU Start-up, RESET Tied to VCC
VCC RESET TIME-OUT
VPOT VRST
tTOUT
INTERNAL RESET
Figure 37. Watchdog Reset during Operation
VCC (HIGH) RESET (HIGH) 1 XTAL CYCLE WDT TIME-OUT
RESET TIME-OUT INTERNAL RESET
tTOUT
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The MCU after five CPU clock-cycles, and can be used when an external clock signal is applied to the XTAL1 pin. This setting does not use the WDT oscillator, and enables very fast start-up from the Sleep, Power-down or Power-save modes if the clock signal is present during sleep. RESET can be connected to VCC directly or via an external pull-up resistor. By holding the pin Low for a period after V CC has been applied, the Power-on Reset period can be extended. Refer to Figure 38 for a timing example on this. Figure 38. MCU Start-up, RESET Controlled Externally
VCC RESET TIME-OUT
VPOT VRST tTOUT
INTERNAL RESET
External Reset
An external reset is generated by a low-level on the AVRRESET pin. When the applied signal reaches the Reset Threshold Voltage - VRST - on its positive edge, the delay timer starts the MCU after the Time-out period tTOUT has expired. When the Watchdog times out, it will generate a short reset pulse of 1 XTAL cycle duration. On the falling edge of this pulse, the delay timer starts counting the Time-out period t TOUT. Time-out period tTOUT is approximately 3 s - at VCC = 3.3V. the period of the time out is voltage dependent. See "Software Control of System Configuration" on page 51. The embedded AVR core has one dedicated 8-bit Interrupt Mask control register: TIMSK - Timer/Counter Interrupt Mask Register. In addition, other enable and mask bits can be found in the peripheral control registers. When an interrupt occurs, the Global Interrupt Enable I-bit is cleared (zero) and all interrupts are disabled. The user software can set (one) the I-bit to enable nested interrupts. The I-bit is set (one) when a Return from Interrupt instruction (RETI) is executed. When the Program Counter is vectored to the actual interrupt vector in order to execute the interrupt handling routine, the hardware clears the corresponding flag that generated the interrupt. Some of the interrupt flags can also be cleared by writing a logic 1 to the flag bit position(s) to be cleared. If an interrupt condition occurs when the corresponding interrupt enable bit is cleared (zero), the interrupt flag will be set and remembered until the interrupt is enabled, or the flag is cleared by software. If one or more interrupt conditions occur when the global interrupt enable bit is cleared (zero), the corresponding interrupt flag(s) will be set and remembered until the global interrupt enable bit is set (one), and will be executed by order of priority. The status register is not automatically stored when entering an interrupt routine and restored when returning from an interrupt routine. This must be handled by software. 63
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External Interrupt Mask/Flag Register - EIMF
Bit $3B ($5B) Read/Write Initial Value 7 INTF3 R/W 0 6 INTF2 R/W 0 5 INTF1 R/W 0 4 INTF0 R/W 0 3 INT3 R/W 0 2 INT2 R/W 0 1 INT1 R/W 0 0 INT0 R/W 0 EIMF
* Bits 3..0 - INT3, 2, 1, 0: External Interrupt Request 3, 2, 1, 0 Enable When an INT3 - INT0 bit is set (one) and the I-bit in the Status Register (SREG) is set (one), the corresponding external pin interrupt is enabled. The external interrupts are always negative edge triggered interrupts, see "Sleep Modes" on page 66. * Bits 7..4 - INTF3, 2, 1, 0: External Interrupt 3, 2, 1, 0 Flags When a falling edge is detected on the INT3, 2, 1, 0 pins, an interrupt request is triggered. The corresponding interrupt flag, INTF3, 2, 1, 0 becomes set (one). If the I-bit in SREG and the corresponding interrupt enable bit, INT3, 2, 1, 0 in EIMF, are set (one), the MCU will jump to the interrupt vector. The flag is cleared when the interrupt routine is executed. Alternatively, the flag is cleared by writing a logic 1 to it.
Timer/Counter Interrupt Mask Register - TIMSK
Bit $39 ($39) Read/Write Initial Value 7 TOIE1 R/W 0 6 OCIE1A R/W 0 5 OCIE1B R/W 0 4 TOIE2 R/W 0 3 TICIE1 R/W 0 2 OCIE2 R/W 0 1 TOIE0 R/W 0 0 OCIE0 R/W 0 TIMSK
* Bit 7 - TOIE1: Timer/Counter1 Overflow Interrupt Enable When the TOIE1 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 Overflow interrupt is enabled. The corresponding interrupt is executed if an overflow in Timer/Counter1 occurs, i.e., when the TOV1 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. * Bit 6 - OCIE1A: Timer/Counter1 Output CompareA Match Interrupt Enable When the OCIE1A bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 CompareA Match interrupt is enabled. The corresponding interrupt is executed if a CompareA match in Timer/Counter1 occurs, i.e., when the OCF1A bit is set in the Timer/Counter Interrupt Flag Register - TIFR. * Bit 5 - OCIE1B: Timer/Counter1 Output CompareB Match Interrupt Enable When the OCIE1B bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 CompareB Match interrupt is enabled. The corresponding interrupt is executed if a CompareB match in Timer/Counter1 occurs, i.e., when the OCF1B bit is set in the Timer/Counter Interrupt Flag Register - TIFR. * Bit 4 - TOIE2: Timer/Counter2 Overflow Interrupt Enable When the TOIE2 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter2 overflow interrupt is enabled. The corresponding interrupt is executed if an overflow in Timer/Counter2 occurs, i.e., when the TOV2 bit is set in the Timer/Counter interrupt flag register - TIFR. * Bit 3 - TICIE1: Timer/Counter1 Input Capture Interrupt Enable When the TICIE1 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter1 input capture event interrupt is enabled. The corresponding interrupt is executed if a capture-triggering event occurs on pin 29, (IC1), i.e., when the ICF1 bit is set in the Timer/Counter interrupt flag register - TIFR.
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* Bit 2 - OCIE2: Timer/Counter2 Output Compare Interrupt Enable When the OCIE2 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter2 Compare Match interrupt is enabled. The corresponding interrupt is executed if a Compare match in Timer/Counter2 occurs, i.e., when the OCF2 bit is set in the Timer/Counter interrupt flag register - TIFR. * Bit 1 - TOIE0: Timer/Counter0 Overflow Interrupt Enable When the TOIE0 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter0 Overflow interrupt is enabled. The corresponding interrupt is executed if an overflow in Timer/Counter0 occurs, i.e., when the TOV0 bit is set in the Timer/Counter Interrupt Flag Register - TIFR. * Bit 0 - OCIE0: Timer/Counter0 Output Compare Interrupt Enable When the OCIE0 bit is set (one) and the I-bit in the Status Register is set (one), the Timer/Counter0 Compare Match interrupt is enabled. The corresponding interrupt is executed if a Compare match in Timer/Counter0 occurs, i.e., when the OCF0 bit is set in the Timer/Counter Interrupt Flag Register - TIFR.
Timer/Counter Interrupt Flag Register - TIFR
Bit $38 ($58) Read/Write Initial Value 7 TOV1 R/W 0 6 OCF1A R/W 0 5 OCF1B R/W 0 4 TOV2 R/W 0 3 ICF1 R/W 0 2 OCF2 R/W 0 1 TOV0 R/W 0 0 OCF0 R/W 0 TIFR
* Bit 7 - TOV1: Timer/Counter1 Overflow Flag The TOV1 is set (one) when an overflow occurs in Timer/Counter1. TOV1 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, TOV1 is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and TOIE1 (Timer/Counter1 Overflow Interrupt Enable), and TOV1 are set (one), the Timer/Counter1 Overflow Interrupt is executed. In PWM mode, this bit is set when Timer/Counter1 advances from $0000. * Bit 6 - OCF1A: Output Compare Flag 1A The OCF1A bit is set (one) when compare match occurs between the Timer/Counter1 and the data in OCR1A - Output Compare Register 1A. OCF1A is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, OCF1A is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and OCIE1A (Timer/Counter1 Compare Interrupt Enable), and the OCF1A are set (one), the Timer/Counter1 Compare A match Interrupt is executed. * Bit 5 - OCF1B: Output Compare Flag 1B The OCF1B bit is set (one) when compare match occurs between the Timer/Counter1 and the data in OCR1B - Output Compare Register 1B. OCF1B is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, OCF1B is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and OCIE1B (Timer/Counter1 Compare match Interrupt Enable), and the OCF1B are set (one), the Timer/Counter1 Compare B match Interrupt is executed. * Bit 4 - TOV2: Timer/Counter2 Overflow Flag The TOV2 bit is set (one) when an overflow occurs in Timer/Counter2. TOV2 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, TOV2 is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and TOIE2 (Timer/Counter1 Overflow Interrupt Enable), and TOV2 are set (one), the Timer/Counter2 Overflow Interrupt is executed. In PWM mode, this bit is set when Timer/Counter2 advances from $00.
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* Bit 3 - ICF1: Input Capture Flag 1 The ICF1 bit is set (one) to flag an input capture event, indicating that the Timer/Counter1 value has been transferred to the input capture register - ICR1. ICF1 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, ICF1 is cleared by writing a logic 1 to the flag. When the SREG I-bit, and TICIE1 (Timer/Counter1 Input Capture Interrupt Enable), and ICF1 are set (one), the Timer/Counter1 Capture Interrupt is executed. * Bit 2 - OCF2: Output Compare Flag 2 The OCF2 bit is set (one) when compare match occurs between Timer/Counter2 and the data in OCR2 - Output Compare Register 2. OCF2 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, OCF2 is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and OCIE2 (Timer/Counter2 Compare Interrupt Enable), and the OCF2 are set (one), the Timer/Counter2 Output Compare Interrupt is executed. * Bit 1 - TOV0: Timer/Counter0 Overflow Flag The TOV0 bit is set (one) when an overflow occurs in Timer/Counter0. TOV0 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, TOV0 is cleared by writing a logic 1 to the flag. When the SREG I-bit, and TOIE0 (Timer/Counter0 Overflow Interrupt Enable), and TOV0 are set (one), the Timer/Counter0 Overflow interrupt is executed. In PWM mode, this bit is set when Timer/Counter0 advances from $00. * Bit 0 - OCF0: Output Compare Flag 0 The OCF0 bit is set (one) when compare match occurs between Timer/Counter0 and the data in OCR0 - Output Compare Register 0. OCF0 is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, OCF0 is cleared by writing a logic 1 to the flag. When the I-bit in SREG, and OCIE0 (Timer/Counter2 Compare Interrupt Enable), and the OCF0 are set (one), the Timer/Counter0 Output Compare Interrupt is executed. Interrupt Response Time The interrupt execution response for all the enabled AVR interrupts is four clock cycles minimum. Four clock cycles after the interrupt flag has been set, the program vector address for the actual interrupt handling routine is executed. During this four clock-cycle period, the Program Counter (2 bytes) is pushed onto the Stack, and the Stack Pointer is decremented by 2. The vector is normally a jump to the interrupt routine, and this jump takes three clock cycles. If an interrupt occurs during execution of a multi-cycle instruction, this instruction is completed before the interrupt is serviced. A return from an interrupt handling routine (same as for a subroutine call routine) takes four clock cycles. During these four clock cycles, the Program Counter (2 bytes) is popped back from the Stack, and the Stack Pointer is incremented by 2. When the AVR exits from an interrupt, it will always return to the main program and execute one more instruction before any pending interrupt is serviced.
Sleep Modes
To enter any of the three Sleep modes, the SE bit in MCUR must be set (one) and a SLEEP instruction must be executed. The SM1 and SM0 bits in the MCUR register select which Sleep mode (Idle, Power-down, or Power-save) will be activated by the SLEEP instruction, see Table 11 on page 52. In Power-down and Power-save modes, the four external interrupts, EXT_INT0...3, and FPGA interrupts, FPGA INT0...3, are triggered as low level-triggered interrupts. If an enabled interrupt occurs while the MCU is in a Sleep mode, the MCU awakes, executes the interrupt routine, and resumes execution from the instruction following SLEEP. The contents of the register file, SRAM, and I/O memory are unaltered. If a reset occurs during Sleep mode, the MCU wakes up and executes from the Reset vector
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Idle Mode When the SM1/SM0 bits are set to 00, the SLEEP instruction makes the MCU enter the Idle mode, stopping the CPU but allowing UARTs, Timer/Counters, Watchdog 2-wire Serial and the Interrupt System to continue operating. This enables the MCU to wake-up from external triggered interrupts as well as internal ones like the Timer Overflow and UART Receive Complete interrupts. When the MCU wakes up from Idle mode, the CPU starts program execution immediately. When the SM1/SM0 bits are set to 10, the SLEEP instruction makes the MCU enter the Power-down mode. In this mode, the external oscillator is stopped, while the external interrupts and the watchdog (if enabled) continue operating. Only an external reset, a watchdog reset (if enabled), or an external level interrupt can wake-up the MCU. In Power-down and Power-save modes, the four external interrupts, EXT_INT0...3, and FPGA interrupts, FPGA_INT0...3, are treated as low-level triggered interrupts. If a level-triggered interrupt is used for wake-up from Power-down mode, the changed level must be held for some time to wake-up the MCU. This makes the MCU less sensitive to noise. The changed level is sampled twice by the watchdog oscillator clock, and if the input has the required level during this time, the MCU will wake-up. The period of the watchdog oscillator is 1 s (n o m in a l) a t 3 .3 V a n d 2 5 C . T h e f re q u e n c y o f t h e w a t ch d o g o s ci lla to r is voltage dependent. When waking up from Power-down mode, there is a delay from the wake-up condition occurs until the wake-up becomes effective. This allows the clock to restart and become stable after having been stopped. The wake-up period is defined by the same time-set bits that define the reset time-out period. The wake-up period is equal to the clock reset period, as shown in Figure 21 on page 89. If the wake-up condition disappears before the MCU wakes up and starts to execute, the interrupt causing the wake-up will not be executed. Power-save Mode When the SM1/SM0 bits are 11, the SLEEP instruction makes the MCU enter the Power-save mode. This mode is identical to power-down, with one exception: If Timer/Counter2 is clocked asynchronously, i.e., the AS2 bit in ASSR is set, Timer/Counter2 will run during sleep. In addition to the power-down wake-up sources, the device can also wake-up from either Timer Overflow or Output Compare event from Timer/Counter2 if the corresponding Timer/Counter2 interrupt enable bits are set in TIMSK. To ensure that the part executes the Interrupt routine when waking up, also set the global interrupt enable bit in SREG. When waking up from Power-save mode by an external interrupt, two instruction cycles are executed before the interrupt flags are updated. When waking up by the asynchronous timer, three instruction cycles are executed before the flags are updated. During these cycles, the processor executes instructions, but the interrupt condition is not readable, and the interrupt routine has not started yet. See Table 2 on page 15 for clock activity during Power-down, Power-save and Idle modes.
Power-down Mode
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JTAG Interface and On-chip Debug System
Features * JTAG (IEEE std. 1149.1 Compliant) Interface * AVR I/O Boundary-scan Capabilities According to the JTAG Standard * Debugger Access to:
- All Internal Peripheral Units - AVR Program and Data SRAM - The Internal Register File - Program Counter/Instruction - FPGA/AVR Interface * Extensive On-chip Debug Support for Break Conditions, Including - Break on Change of Program Memory Flow - Single Step Break - Program Memory Breakpoints on Single Address or Address Range - Data Memory Breakpoints on Single Address or Address Range - FPGA Hardware Break - Frame Memory Breakpoint on Single Address * On-chip Debugging Supported by AVR Studio version 4 or above
Overview
The AVR IEEE std. 1149.1 compliant JTAG interface is used for on-chip debugging. The On-Chip Debug support is considered being private JTAG instructions, and distributed within ATMEL and to selected third-party vendors only. Figure 39 shows a block diagram of the JTAG interface and the On-Chip Debug system. The TAP Controller is a state machine controlled by the TCK and TMS signals. The TAP Controller selects either the JTAG Instruction Register or one of several Data Registers as the scan chain (shift register) between the TDI - input and TDO - output. The Instruction Register holds JTAG instructions controlling the behavior of a Data Register. Of the Data Registers, the ID-Register, Bypass Register, and the AVR I/O Boundary-Scan Chain are used for board-level testing. The Internal Scan Chain and Break-Point Scan Chain are used for On-Chip debugging only.
The Test Access Port - TAP
The JTAG interface is accessed through four of the AVR's pins. In JTAG terminology, these pins constitute the Test Access Port - TAP. These pins are: * * * * TMS: Test Mode Select. This pin is used for navigating through the TAP-controller state machine. TCK: Test Clock. JTAG operation is synchronous to TCK TDI: Test Data In. Serial input data to be shifted in to the Instruction Register or Data Register (Scan Chains) TDO: Test Data Out. Serial output data from Instruction register or Data Register
The IEEE std. 1149.1 also specifies an optional TAP signal; TRST - Test ReSeT - which is not provided. When the JTAGEN bit is unprogrammed, these four TAP pins revert to normal operation. When programmed, the input TAP signals are internally pulled High and the JTAG is enabled for Boundary-Scan. System Designer sets this bit by default. For the On-Chip Debug system, in addition the RESET pin is monitored by the debugger to be able to detect external reset sources. The debugger can also pull the RESET pin Low to reset the whole system, assuming only open collectors on reset line are used in the application.
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Figure 39. Block Diagram
PORT E
DEVICE BOUNDARY
AVR BOUNDARY-SCAN CHAIN FPGA-AVR SCAN CHAIN
TDI TDO TCK TMS
TAP CONTROLLER
FPGA-SRAM SCAN CHAIN
AVR CPU JTAG INSTRUCTION REGISTER DEVICE ID REGISTER M U X BYPASS REGISTER M U X PROGRAM/DATA SRAM INTERNAL SCAN CHAIN PC Instruction
BREAKPOINT UNIT
FLOW CONTROL UNIT DIGITAL PERIPHERAL UNITS
BREAKPOINT SCAN CHAIN ADDRESS DECODER
OCD STATUS AND CONTROL
OCD / AVR CORE COMMUNICATION INTERFACE
AVR RESET SCAN CHAIN
RESET CONTROL UNIT
2-wire Serial
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Figure 40. TAP Controller State Diagram
1 Test-Logic-Reset 0 0 Run-Test/Idle 1 Select-DR Scan 0 1 Capture-DR 0 Shift-DR 1 Exit1-DR 0 Pause-DR 1 0 Exit2-DR 1 Update-DR 1 0 0 0 1 0 1 1 Select-IR Scan 0 Capture-IR 0 Shift-IR 1 Exit1-IR 0 Pause-IR 1 Exit2-IR 1 Update-IR 1 0 0 1 0 1
TAP Controller
The TAP controller is a 16-state finite state machine that controls the operation of the Boundary-Scan circuitry and On-Chip Debug system. The state transitions depicted in Figure 40 depend on the signal present on TMS (shown adjacent to each state transition) at the time of the rising edge at TCK. The initial state after a Power-On Reset is Test-Logic-Reset. As a definition in this document, the LSB is shifted in and out first for all shift registers.
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Assuming Run-Test/Idle is the present state, a typical scenario for using the JTAG interface is * At the TMS input, apply the sequence 1, 1, 0, 0 at the rising edges of TCK to enter the Shift Instruction Register - Shift-IR state. While TMS is Low, shift the 4 bit JTAG instructions into the JTAG instruction register from the TDI input at the rising edge of TCK, while the captured IR-state 0x01 is shifts out on the TDO pin. The JTAG Instruction selects a particular Data Register as path between TDI and TDO and controls the circuitry surrounding the selected Data Register. Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. The instruction is latched onto the parallel output from the shift register path in the Update-IR state. The Exit-IR, Pause-IR, and Exit2-IR states are only used for navigating the state machine. At the TMS input, apply the sequence 1, 0, 0 at the rising edges of TCK to enter the Shift Data Register - Shift-DR state. While TMS is Low, upload the selected Data Register (selected by the present JTAG instruction in the JTAG Instruction Register) from the TDI input at the rising edge of TCK. At the same time, the parallel inputs to the Data Register captured in the Capture-DR state shifts out on the TDO pin. Apply the TMS sequence 1, 1, 0 to re-enter the Run-Test/Idle state. If the selected Data Register has a latched parallel-output, the latching takes place in the Update-DR state. The Exit-DR, Pause-DR, and Exit2-DR states are only used for navigating the state machine.
*
*
*
As shown in Figure 40 on page 70, the Run-Test/Idle (1) state need not be entered between selecting JTAG instruction and using Data Registers, and some JTAG instructions may select certain functions to be performed in the Run-Test/Idle, making it unsuitable as an Idle state.
Note: 1. Independent of the initial state of the TAP Controller, the Test-Logic-Reset state can always be entered by holding TMS High for 5 TCK clock periods.
Using the Boundary-scan Chain Using the On-chip Debug System
A complete description of the Boundary-Scan capabilities are given in the section "IEEE 1149.1 (JTAG) Boundary-scan" on page 73. As shown in Figure 39, the hardware support for On-Chip Debugging consists mainly of * * * * * A scan chain on the interface between the internal AVR CPU and the internal peripheral units A breakpoint unit A communication interface between the CPU and JTAG system A scan chain on the interface between the internal AVR CPU and the FPGA A scan chain on the interface between the internal Program/Data SRAM and the FPGA
All read or modify/write operations needed for implementing the Debugger are done by applying AVR instructions via the internal AVR CPU Scan Chain. The CPU sends the result to an I/O memory mapped location which is part of the communication interface between the CPU and the JTAG system.
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The Breakpoint Unit implements Break on Change of Program Flow, Single Step Break, 2 Program Memory Breakpoints, and 2 combined break points. Together, the 4 break-points can be configured as either: * * * * * * 4 single Program Memory break points 3 Single Program Memory break point + 1 single Data Memory break point 2 single Program Memory break points + 2 single Data Memory break points 2 single Program Memory break points + 1 Program Memory break point with mask (`range break point') 2 single Program Memory break points + 1 Data Memory break point with mask (`range break point') 1 single Frame Memory break point is available parallel to all the above combinations
A list of the On-Chip Debug specific JTAG instructions is given in "On-chip Debug Specific JTAG Instructions". Atmel supports the On-Chip Debug system with the AVR Studio front-end software for PCs. The details on hardware implementation and JTAG instructions are therefore irrelevant for the user of the On-Chip Debug system. The JTAG Enable bit must be set (one) in the System Control Register to enable the JTAG Test Access Port. In addition, the On-chip Debug Enable bit must be set (one). The AVR Studio enables the user to fully control execution of programs on an AVR device with On-Chip Debug capability, AVR In-Circuit Emulator, or the built-in AVR Instruction Set Simulator. AVR Studio supports source level execution of Assembly programs assembled with Atmel Corporation's AVR Assembler and C programs compiled with third-party vendors' compilers. AVR Studio runs under Microsoft Windows(R) 95/98/2000 and Microsoft WindowsNT(R). All necessary execution commands are available in AVR Studio, both on source level and on disassembly level. The user can execute the program, single step through the code either by tracing into or stepping over functions, step out of functions, place the cursor on a statement and execute until the statement is reached, stop the execution, and reset the execution target. In addition, the user can have up to 2 data memory breakpoints, alternatively combined as a mask (range) break-point.
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On-chip Debug Specific JTAG Instructions The On-Chip debug support is considered being private JTAG instructions, and distributed within ATMEL and to selected third-party vendors only. Table 16 lists the instruction opcode. Table 16. JTAG Instruction and Code
JTAG Instruction EXTEST IDCODE SAMPLE_PRELOAD RESERVED PRIVATE PRIVATE PRIVATE RESERVED PRIVATE PRIVATE PRIVATE PRIVATE AVR_RESET RESERVED RESERVED BYPASS 4-bit Code $0 (0000) $1 (0001) $2 (0010) $3 (0011) $4 (0100) $5 (0101) $6 (0110) $7 (0111) $8 (1000) $9 (1001) $A (1010) $B (1011) $C (1100) $D (1101) $E (1110) $F (1111) Selected Scan Chain AVR I/O Boundary Device ID AVR I/O Boundary N/A FPSLIC On-chip Debug System FPSLIC On-chip Debug System FPSLIC On-chip Debug System N/A FPSLIC On-chip Debug System FPSLIC On-chip Debug System FPSLIC On-chip Debug System FPSLIC On-chip Debug System AVR Reset N/A N/A Bypass # Bits 69 32 69 - - - - - - - - - 1 - - 1
IEEE 1149.1 (JTAG) Boundary-scan
Features * * * * *
JTAG (IEEE std. 1149.1 compliant) Interface Boundary-scan Capabilities According to the JTAG Standard Full Scan of All Port Functions Supports the Optional IDCODE Instruction Additional Public AVR_RESET Instruction to Reset the AVR
System Overview
The Boundary-Scan chain has the capability of driving and observing the logic levels on the AVR's digital I/O pins. At system level, all ICs having JTAG capabilities are connected serially by the TDI/TDO signals to form a long shift register. An external controller sets up the devices to drive values at their output pins, and observe the input values received from other devices. The controller compares the received data with the expected result. In this way, BoundaryScan provides a mechanism for testing interconnections and integrity of components on Printed Circuits Boards by using the 4 TAP signals only. The four IEEE 1149.1 defined mandatory JTAG instructions IDCODE, BYPASS, SAMPLE/PRELOAD, and EXTEST, as well as the AVR specific public JTAG instruction AVR_RESET can be used for testing the Printed Circuit Board. Initial scanning of the data register path will show the ID-code of the device, since IDCODE is the default JTAG instruction. It may be desirable to have the AVR device in reset during test mode. If not reset, inputs to the device may be determined by the scan operations, and the internal software may be in an
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undetermined state when exiting the test mode. If needed, the BYPASS instruction can be issued to make the shortest possible scan chain through the device. The AVR can be set in the reset state either by pulling the external AVR RESET pin Low, or issuing the AVR_RESET instruction with appropriate setting of the Reset Data Register. The EXTEST instruction is used for sampling external pins and loading output pins with data. The data from the output latch will be driven out on the pins as soon as the EXTEST instruction is loaded into the JTAG IR-register. Therefore, the SAMPLE/PRELOAD should also be used for setting initial values to the scan ring, to avoid damaging the board when issuing the EXTEST instruction for the first time. SAMPLE/PRELOAD can also be used for taking a snapshot of the AVR's external pins during normal operation of the part. The JTAG Enable bit must be programmed and the JTD bit in the I/O register MCUR must be cleared to enable the JTAG Test Access Port. When using the JTAG interface for Boundary-Scan, using a JTAG TCK clock frequency higher than the internal chip frequency is possible. The chip clock is not required to run. Data Registers The Data Registers are selected by the JTAG instruction registers described in section "Boundary-scan Specific JTAG Instructions" on page 75. The data registers relevant for Boundary-Scan operations are: * * * * Bypass Register Device Identification Register AVR Reset Register AVR Boundary-Scan Chain
Bypass Register
The Bypass register consists of a single shift-register stage. When the Bypass register is selected as path between TDI and TDO, the register is reset to 0 when leaving the CaptureDR controller state. The Bypass register can be used to shorten the scan chain on a system when the other devices are to be tested. Figure 41 shows the structure of the Device Identification register. Figure 41. The format of the Device Identification Register
MSB Bit Device ID 31 Version 4 bits 28 27 Part Number 16 bits 12 11 Manufacturer ID 11 bits 1 LSB 0 1 1 bit
Device Identification Register
Version Version is a 4-bit number identifying the revision of the component. The relevant version numbers are shown in Table 17. Table 17. JTAG Part Version
Device AT94K05 AT94K10 AT94K40 Version (Binary Digits) - 0010 -
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Part Number The part number is a 16 bit code identifying the component. The JTAG Part Number for AVR devices is listed in Table 18. Table 18. JTAG Part Number
Device AT94K05 AT94K10 AT94K40 Part Number (Hex) 0xdd77 0xdd73 0xdd76
Manufacturer ID The manufacturer ID for ATMEL is 0x01F (11 bits).
AVR Reset Register
The AVR Reset Register is a Test Data Register used to reset the AVR. A high value in the Reset Register corresponds to pulling the external AVRResetn Low. The AVR is reset as long as there is a high value present in the AVR Reset Register. Depending on the Bit settings for the clock options, the CPU will remain reset for a Reset Time-Out Period after releasing the AVR Reset Register. The output from this Data Register is not latched, so the reset will take place immediately, see Figure 42. Figure 42. Reset Register
To TDO
From other internal and external reset sources From TDI Internal AVR Reset
D
Q
ClockDR * AVR_RESET
Boundary-scan Chain
The Boundary-scan Chain has the capability of driving and observing the logic levels on the AVR's digital I/O pins. See "Boundary-scan Chain" on page 76 for a complete description.
Boundary-scan Specific JTAG Instructions
The instruction register is 4-bit wide, supporting up to 16 instructions. Listed below are the JTAG instructions useful for Boundary-Scan operation. Note that the optional HIGHZ instruction is not implemented. As a definition in this data sheet, the LSB is shifted in and out first for all shift registers. The OPCODE for each instruction is shown behind the instruction name in hex format. The text describes which data register is selected as path between TDI and TDO for each instruction.
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EXTEST; $0
Mandatory JTAG instruction for selecting the Boundary-Scan Chain as Data Register for testing circuitry external to the AVR package. For port-pins, Pull-up Disable, Output Control, Output Data, and Input Data are all accessible in the scan chain. For Analog circuits having off-chip connections, the interface between the analog and the digital logic is in the scan chain. The contents of the latched outputs of the Boundary-Scan chain are driven out as soon as the JTAG IR-register is loaded by the EXTEST instruction. The active states are: * * * Capture-DR: Data on the external pins are sampled into the Boundary-Scan Chain. Shift-DR: The Internal Scan Chain is shifted by the TCK input. Update-DR: Data from the scan chain is applied to output pins.
IDCODE; $1
Optional JTAG instruction selecting the 32-bit ID register as Data Register. The ID register consists of a version number, a device number and the manufacturer code chosen by JEDEC. This is the default instruction after power-up. The active states are: * * Capture-DR: Data in the IDCODE register is sampled into the Boundary-Scan Chain. Shift-DR: The IDCODE scan chain is shifted by the TCK input.
SAMPLE_PRELOAD; $2
Mandatory JTAG instruction for pre-loading the output latches and taking a snap-shot of the input/output pins without affecting the system operation. However, the output latches are not connected to the pins. The Boundary-Scan Chain is selected as Data Register. The active states are: * * * Capture-DR: Data on the external pins are sampled into the Boundary-Scan Chain. Shift-DR: The Boundary-Scan Chain is shifted by the TCK input. Update-DR: Data from the Boundary-Scan chain is applied to the output latches. However, the output latches are not connected to the pins.
AVR_RESET; $C
The AVR specific public JTAG instruction for forcing the AVR device into the Reset Mode or releasing the JTAG reset source. The TAP controller is not reset by this instruction. The one bit Reset Register is selected as Data Register. Note that the reset will be active as long as there is a logic "1" in the Reset Chain. The output from this chain is not latched. The active state is: * Shift-DR: The Reset Register is shifted by the TCK input.
BYPASS; $F
Mandatory JTAG instruction selecting the Bypass Register for Data Register. The active states are: * * Capture-DR: Loads a logic "0" into the Bypass Register. Shift-DR: The Bypass Register cell between TDI and TDO is shifted.
Boundary-scan Chain
The Boundary-Scan chain has the capability of driving and observing the logic levels on the AVR's digital I/O pins. Figure 43 shows the boundary-scan cell for bi-directional port pins with pull-up function. The cell consists of a standard boundary-scan cell for the pull-up function, and a bi-directional pin cell that combines the three signals Output Control (OC), Output Data (OD), and Input Data (ID), into only a two-stage shift register.
Scanning the Digital Port Pins
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AT94K Series FPSLIC
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AT94K Series FPSLIC
Figure 43. Boundary-scan Cell For Bi-directional Port Pin with Pull-up Function
ShiftDR To Next Cell EXTEST Vcc
Pullup Disable (PLD) FF2 0 D 1 G Q D Q LD2
0 1
Output Control (OC) FF1 0 D 1 G Q D Q LD1 0 1
Output Data (OD) Port Pin (PXn)
0 1 0
FF0 D 1 Q
LD0 D G Q
0 1
Input Data (ID)
From Last Cell
ClockDR
UpdateDR
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Rev. 1138F-FPSLI-06/02
Figure 44 shows a simple digital Port Pin as described in the section "I/O Ports" on page 147. The Boundary-Scan details from Figure 43 replaces the dashed box in Figure 44. Figure 44. General Port Pin Schematic Diagram
RD PULL-UP
PLD
PUD
RESET
Q
D
DDXn
C
OC
RESET
PXn
OD
Q D PORTXn C RL
ID
WP
RP
WP: WD: RL: RP: RD: n: PUD:
WRITE PORTX WRITE DDRX READ PORTX LATCH READ PORTX PIN READ DDRX 0-7 PULL-UP DISABLE
PuD: JTAG PULL-UP DISABLE OC: JTAG OUTPUT CONTROL OD: JTAG OUTPUT DATA ID: JTAG INPUT DATA
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AT94K Series FPSLIC
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DATA BUS
WD
AT94K Series FPSLIC
When no alternate port function is present, the Input Data - ID corresponds to the PINn register value, Output Data corresponds to the PORTn register, Output Control corresponds to the Data Direction (DDn) register, and the PuLL-up Disable (PLD) corresponds to logic expression (DDn OR NOT(PORTBn)). Digital alternate port functions are connected outside the dashed box in Figure 44 to make the scan chain read the actual pin value.
Scanning AVR RESET
Multiple sources contribute to the internal AVR reset; therefore, the AVR reset pin is not observed. Instead, the internal AVR reset signal output from the Reset Control Unit is observed, see Figure 45. The scanned signal is active High if AVRResetn is Low and enabled or the device is in general reset (Resetn or power-on) or configuration download. Figure 45. Observe-only Cell
ShiftDR
To Next Cell
RESET CONTROL UNIT FF1 0 D 1 Q
To System Logic
From Previous Cell
ClockDR
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Scanning 2-wire Serial
The SCL and SDA pins are open drain, bi-directional and enabled separately. The "Enable Output" bits (active High) in the scan chain are supported by general boundary-scan cells. Enabling the output will drive the pin Low from a tri-state. External pull-ups on the 2-wire bus are required to pull the pins High if the output is disabled. The "Data Out/In" and "Clock Out/In" bits in the scan chain are observe-only cells. Figure 46 shows how each pin is connected in the scan chain. Figure 46. Boundary-scan Cells for 2-wire Serial
From Previous Cell To 2-wire Serial Logic Data or Clock Out/In (Observe Only Cell) SDA or SCL
From 2-wire Serial Logic
Enable Output (General Boundary Scan Cell)
To Next Cell
Scanning the Clock Pins
Figure 47 shows how each oscillator with external connection is supported in the scan chain. The Enable signal is supported with a general boundary-scan cell, while the oscillator/clock output is attached to an observe-only cell. In addition to the main clock, the timer oscillator is scanned in the same way. The output from the internal RC-Oscillator is not scanned, as this oscillator does not have external connections. Figure 47. Boundary-scan Cells for Oscillators and Clock Options
XTAL1/TOSC1 XTAL2/TOSC2
ShiftDR From digital logic 0 1
To next cell
EXTEST 0 1
Oscillator
ShiftDR
To next cell To system logic FF1
ENABLE
OUTPUT 0 1 DQ
DQ
DQ G
From ClockDR UpdateDR previous cell
From ClockDR previous cell
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AT94K Series FPSLIC
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AT94K Series FPSLIC
Scanning an oscillator output gives unpredictable results as there is a frequency drift between the internal oscillator and the JTAG TCK clock. The clock configuration is programmed in the SCR. As an SCR bit is not changed run-time, the clock configuration is considered fixed for a given application. The user is advised to scan the same clock option as to be used in the final system. The enable signals are supported in the scan chain because the system logic can disable clock options in sleep modes, thereby disconnecting the oscillator pins from the scan path if not provided. The XTAL or TOSC "Clock In" Scan chain bit will always capture "1" if the oscillator is disabled ("Enable Clock" bit is active Low). FPSLIC Boundary-scan Order Table 19 shows the Scan order between TDI and TDO when the Boundary-Scan chain is selected as data path. Bit 0 is the LSB; the first bit scanned in, and the first bit scanned out. In Figure 43, "Data Out/In - PXn" corresponds to FF0, "Enable Output - PXn" corresponds to FF1, and "Pull-up - PXn" corresponds to FF2. Table 19. AVR I/O Boundary Scan - JTAG Instructions $0/$2
I/O Ports Description Data Out/In - PE7 Enable Output - PE7 Pull-up - PE7 Data Out/In - PE6 Enable Output - PE6 Pull-up - PE6 Data Out/In - PE5 Enable Output - PE5 Pull-up - PE5 Data Out/In - PE4 Enable Output - PE4 Pull-up - PE4 PORTE Data Out/In - PE3 Enable Output - PE3 Pull-up - PE3 Data Out/In - PE2 Enable Output - PE2 Pull-up - PE2 Data Out/In - PE1 Enable Output - PE1 Pull-up - PE1 Data Out/In - PE0 Enable Output - PE0 Pull-up - PE0 56 55 54 53 52 51 50 49 48 47 46 45 Bit 68 67 66 65 64 63 62 61 60 59 58 57 <- TDI
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Table 19. AVR I/O Boundary Scan - JTAG Instructions $0/$2
I/O Ports Description Data Out/In - PD7 Enable Output - PD7 Pull-up - PD7 Data Out/In - PD6 Enable Output - PD6 Pull-up - PD6 Data Out/In - PD5 Enable Output - PD5 Pull-up - PD5 Data Out/In - PD4 Enable Output - PD4 Pull-up - PD4 PORTD Data Out/In - PD3 Enable Output - PD3 Pull-up - PD3 Data Out/In - PD2 Enable Output - PD2 Pull-up - PD2 Data Out/In - PD1 Enable Output - PD1 Pull-up - PD1 Data Out/In - PD0 Enable Output - PD0 Pull-up - PD0 Input with Pull-up - INTP3 Input with Pull-up - INTP2 EXT. INTERRUPTS Input with Pull-up - INTP1 Input with Pull-up - INTP0 Data Out/In - TX1 Enable Output - TX1 UART1 Pull-up - TX1 Input with Pull-up - RX1 Data Out/In - TX0 Enable Output - TX0 UART0 Pull-up - TX0 Input with Pull-up - RX0 10 9(1) 14 13(1) 12 11 32 31 30 29 28 27 26 25 24 23 22 21 20(1) 19(1) 18(1) 17(1) 16 15 Bit 44 43 42 41 40 39 38 37 36 35 34 33
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AT94K Series FPSLIC
Table 19. AVR I/O Boundary Scan - JTAG Instructions $0/$2
I/O Ports XTAL Enable Clock - XTAL 1 Clock In - TOSC 1 TOSC Enable Clock - TOSC 1 Data Out/In - SDA Enable Output - SDA 2-wire Serial Clock Out/In - SCL Enable Output - SCL
(2)
Description Clock In - XTAL1
Bit 8(1) 7 6(1) 5 4(1) 3 2(1) 1 0(1) -> TDO
AVR Reset
Notes:
1. Observe-only scan cell. 2. AVR Reset is High (one) if AVRResetn activated (Low) and enabled or the device is in general reset (Resetn or power-on) or configuration download.
Table 20. Bit EXTEST and SAMPLE_PRELOAD
Bit Type Data Out/In - PXn EXTEST Defines value driven if enabled. Capture-DR grabs signal on pad. 1 = output drive enabled. Capture-DR grabs output enable scan latch. 1 = pull-up disabled. Capture-DR grabs pull-up control from the AVR. Observe only. Capture-DR grabs signal from pad. Defines value driven if enabled. Capture-DR grabs signal on pad. 1 = output drive enabled. Capture-DR grabs output enable scan latch. 1 = pull-up disabled. Capture-DR grabs pull-up control from the AVR. Observe only. Capture-DR grabs signal from pad. Observe only. Capture-DR grabs signal from pad. 1 = clock disabled. Capture-DR grabs clock enable from the AVR. SAMPLE_PRELOAD Capture-DR grabs signal from pad if output disabled, or from the AVR if the output drive is enabled. Capture-DR grabs output enable from the AVR. Capture-DR grabs pull-up control from the AVR. Capture-DR grabs signal from pad. Capture-DR always grabs "0" since Tx input is NC and tied to ground internally. Capture-DR grabs output enable from the AVR. Capture-DR grabs pull-up control from the AVR. Capture-DR grabs signal from pad. Capture-DR grabs signal from pad if clock is enabled, "1" if disabled. Capture-DR grabs enable from the AVR.
Enable Output - PXn
Pull-up - PXn
Input with Pull-up - INTPn Data Out - TXn
Enable Output - TXn
Pull-up - TXn
Input with Pull-up - RXn Clock In - XTAL1
Enable Clock - XTAL 1
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Table 20. Bit EXTEST and SAMPLE_PRELOAD
Bit Type Clock In - TOSC 1 EXTEST Observe only. Capture-DR grabs signal from pad. 1 = clock disabled. Capture-DR grabs clock enable from the AVR. Observe only. Capture-DR grabs signal from pad. 1 = drive "0" 0 = drive disabled, bus pull-up Capture-DR grabs output enable scan latch. Observe only. Capture-DR grabs signal from pad. 1 = drive "0" 0 = drive disabled, bus pull-up Capture-DR grabs output enable scan latch. Internal, observe only. Capture-DR grabs internal AVR reset signal. SAMPLE_PRELOAD Capture-DR grabs signal from pad if clock is enabled, "1" if disabled. Capture-DR grabs enable from the AVR. Capture-DR grabs signal from pad. Capture-DR grabs output enable from the AVR.
Enable Clock - TOSC 1 Data Out/In - SDA Enable Output - SDA
Clock Out/In - SCL Enable Output - SCL
Capture-DR grabs signal from pad. Capture-DR grabs output enable from the AVR.
AVR Reset
Capture-DR grabs internal AVR reset signal.
Boundary-scan Description Language Files
Boundary-Scan Description Language (BSDL) files describe Boundary-Scan capable devices in a standard format used by automated test-generation software. The order and function of bits in the Boundary-Scan data register are included in this description. A BSDL file for AT94K Family is available.
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AT94K Series FPSLIC
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AT94K Series FPSLIC
Timer/Counters
The FPSLIC provides three general-purpose Timer/Counters: two 8-bit T/Cs and one 16-bit T/C. Timer/Counter2 can optionally be asynchronously clocked from an external oscillator. This oscillator is optimized for use with a 32.768 kHz watch crystal, enabling use of Timer/Counter2 as a Real-time Clock (RTC). Timer/Counters 0 and 1 have individual prescaling selection from the same 10-bit prescaling timer. Timer/Counter2 has its own prescaler. Both these prescalers can be reset by setting the corresponding control bits in the Special Functions I/O Register (SFIOR). See "Special Function I/O Register - SFIOR" on page 86 for a detailed description. These Timer/Counters can either be used as a timer with an internal clock time-base or as a counter with an external pin connection which triggers the counting. For Timer/Counters 0 and 1, see Figure 48, the four prescaled selections are: CK/8, CK/64, CK/256 and CK/1024, where CK is the oscillator clock. For the two Timer/Counters 0 and 1, CK, external source, and stop, can also be selected as clock sources. Setting the PSR10 bit in SFIOR resets the prescaler. This allows the user to operate with a predictable prescaler. Note that Timer/Counter1 and Timer/Counter0 share the same prescaler and a prescaler reset will affect both Timer/Counters. Figure 48. Prescaler for Timer/Counter0 and 1
Clear
Timer/Counter Prescalers
PSR10
TCK1
TCK0
The clock source for Timer/Counter2 prescaler, see Figure 49, is named PCK2. PCK2 is by defau lt conne cte d to th e main system clo ck CK. By setting the AS2 bit in ASSR, Timer/Counter2 is asynchronously clocked from the TOSC1 pin. This enables use of Timer/Counter2 as a Real-time Clock (RTC). When AS2 is set, pins TOSC1 and TOSC2 are disconnected from Port D. A crystal can then be connected between the TOSC1 and TOSC2 pins to serve as an independent clock source for Timer/Counter2. The oscillator is optimized for use with a 32.768 kHz crystal. Alternatively, an external clock signal can be applied to TOSC1. The frequency of this clock must be lower than one fourth of the CPU clock and not higher than 1 MHz. Setting the PSR2 bit in SFIOR resets the prescaler. This allows the user to operate with a predictable prescaler.
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Rev. 1138F-FPSLI-06/02
Figure 49. Timer/Counter2 Prescaler
CK TOSC1 PCK2 Clear
PCK2/8
10-BIT T/C PRESCALER
PCK2/1024 PCK2/128 PCK2/256 PCK2/32 PCK2/64
AS2
PSR2
0
CS20 CS21 CS22
TIMER/COUNTER2 CLOCK SOURCE TCK2
Special Function I/O Register - SFIOR
Bit $30 ($50) Read/Write Initial Value 7 R 0 6 R 0 5 R 0 4 R 0 3 R 0 2 R 0 1 PSR2 R/W 0 0 PSR10 R/W 0 SFIOR
* Bits 7..2 - Res: Reserved Bits These bits are reserved bits in the FPSLIC and are always read as zero. * Bit 1 - PSR2: Prescaler Reset Timer/Counter2 When this bit is set (one) the Timer/Counter2 prescaler will be reset. The bit will be cleared by the hardware after the operation is performed. Writing a zero to this bit will have no effect. This bit will always be read as zero if Timer/Counter2 is clocked by the internal CPU clock. If this bit is written when Timer/Counter2 is operating in asynchronous mode; however, the bit will remain as one until the prescaler has been reset. See "Asynchronous Operation of Timer/Counter2" on page 94 for a detailed description of asynchronous operation. * Bit 0 - PSR10: Prescaler Reset Timer/Counter1 and Timer/Counter0 When this bit is set (one) the Timer/Counter1 and Timer/Counter0 prescaler will be reset. The bit will be cleared by the hardware after the operation is performed. Writing a zero to this bit will have no effect. Note that Timer/Counter1 and Timer/Counter0 share the same prescaler and a reset of this prescaler will affect both timers. This bit will always be read as zero.
8-bit Timers/Counters T/C0 and T/C2
Figure 50 shows the block diagram for Timer/Counter0. Figure 51 shows the block diagram for Timer/Counter2.
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AT94K Series FPSLIC
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AT94K Series FPSLIC
Figure 50. Timer/Counter0 Block Diagram
T/C0 OVER- T/C0 COMPARE FLOW IRQ MATCH IRQ
OCIE1A
OCIE1B
TICIE1
OCIE2
TOIE2
OCIE0
TOIE1
TOIE0
8-BIT DATA BUS
TIMER INT. MASK REGISTER (TIMSK)
TOV1
TIMER INT. FLAG REGISTER (TIFR)
FOC0 OCF1A OCF1B OCF2 OCF0 TOV2 TOV0 ICF1
TOV0
OCF0
T/C0 CONTROL REGISTER (TCCR0)
PWM0 COM01 COM00 CTC0 CS02 CS01 CS00
SPECIAL FUNCTIONS IO REGISTER (SFIOR)
PSR10
PSR10
7 TIMER/COUNTER0 (TCNT0)
0
T/C CLEAR T/C CLK SOURCE UP/DOWN
CONTROL LOGIC
CK
T0
7 8-BIT COMPARATOR
0
7 OUTPUT COMPARE REGISTER0 (OCR0)
0
Figure 51. Timer/Counter2 Block Diagram
T/C2 OVER- T/C2 COMPARE FLOW IRQ MATCH IRQ
8-BIT DATA BUS 8-BIT ASYNCH T/C2 DATA BUS
OCIE1A OCIE1B
TICIE1
OCIE2
TOIE2
OCIE0
TOIE1
TOIE0
OCF2
TOV2
TIMER INT. MASK REGISTER (TIMSK)
TOV1
TIMER INT. FLAG REGISTER (TIFR)
FOC2 OCF1A TOV0 OCF1B OCF2 OCF0 TOV2 ICF1
T/C2 CONTROL REGISTER (TCCR2)
PWM2 COM21 COM20 CS22 CTC2 CS21 CS20
SPECIAL FUNCTIONS IO REGISTER (SFIOR)
PSR2
7 TIMER/COUNTER2 (TCNT2)
0
T/C CLEAR T/C CLK SOURCE UP/DOWN
CONTROL LOGIC
CK TOSC1
7 8-BIT COMPARATOR
0
7 OUTPUT COMPARE REGISTER2 (OCR2)
0 ASYNCH. STATUS REGISTER (ASSR)
AS2 OCR2UB ICR2UB TC2UB
CK TCK2
SYNCH UNIT
PSR2
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Rev. 1138F-FPSLI-06/02
The 8-bit Timer/Counter0 can select the clock source from CK, prescaled CK, or an external pin. The 8-bit Timer/Counter2 can select the clock source from CK, prescaled CK or external TOSC1. Both Timers/Counters can be stopped as described in section "Timer/Counter0 Control Register - TCCR0" on page 88 and "Timer/Counter2 Control Register - TCCR2" on page 88. The various status flags (overflow and compare match) are found in the Timer/Counter Interrupt Flag Register (TIFR). Control signals are found in the Timer/Counter Control Register (TCCR0 and TCCR2). The interrupt enable/disable settings are found in the Timer/Counter Interrupt Mask Register - TIMSK. When Timer/Counter0 is externally clocked, the external signal is synchronized with the oscillator frequency of the CPU. To assure proper sampling of the external clock, the minimum time between two external clock transitions must be at least one internal CPU clock period. The external clock signal is sampled on the rising edge of the internal CPU clock. The 8-bit Timer/Counters feature both a high-resolution and a high-accuracy usage with the lower prescaling opportunities. Similarly, the high prescaling opportunities make the Timer/Counter0 useful for lower speed functions or exact-timing functions with infrequent actions. Timer/Counters 0 and 2 can also be used as 8-bit Pulse Width Modulators (PWM). In this mode, the Timer/Counter and the output compare register serve as a glitch-free, stand-alone PWM with centered pulses. See "Timer/Counter 0 and 2 in PWM Mode" on page 91 for a detailed description on this function.
Timer/Counter0 Control Register - TCCR0
Bit $33 ($53) Read/Write Initial Value 7 FOC0 R/W 0 6 PWM0 R/W 0 5 COM01 R/W 0 4 COM00 R/W 0 3 CTC0 R/W 0 2 CS02 R/W 0 1 CS01 R/W 0 0 CS00 R/W 0 TCCR0
Timer/Counter2 Control Register - TCCR2
Bit $27 ($47) Read/Write Initial Value 7 FOC2 R/W 0 6 PWM2 R/W 0 5 COM21 R/W 0 4 COM20 R/W 0 3 CTC2 R/W 0 2 CS22 R/W 0 1 CS21 R/W 0 0 CS20 R/W 0 TCCR2
* Bit 7 - FOC0/FOC2: Force Output Compare Writing a logic 1 to this bit forces a change in the compare match output pin PE1 (Timer/Counter0) and PE3 (Timer/Counter2) according to the values already set in COMn1 and COMn0. If the COMn1 and COMn0 bits are written in the same cycle as FOC0/FOC2, the new settings will not take effect until next compare match or Forced Output Compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COMn1 and COMn0 happens as if a Compare Match had occurred, but no interrupt is generated and the Timer/Counters will not be cleared even if CTC0/CTC2 is set. The FOC0/FOC2 bits will always be read as zero. The setting of the FOC0/FOC2 bits has no effect in PWM mode. * Bit 6 - PWM0/PWM2: Pulse Width Modulator Enable When set (one) this bit enables PWM mode for Timer/Counter0 or Timer/Counter2. This mode is described on page 91.
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AT94K Series FPSLIC
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AT94K Series FPSLIC
* Bits 5,4 - COM01, COM00/COM21, COM20: Compare Output Mode, Bits 1 and 0 The COMn1 and COMn0 control bits determine any output pin action following a compare match in Timer/Counter0 or Timer/Counter2. Output pin actions affect pins PE1(OC0) or PE3(OC2). This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. The control configuration is shown in Table 21. Table 21. Compare Output Mode Select(1)
COMn1 0 0 1 1 Notes: COMn0 0 1 0 1 Description Timer/Counter disconnected from output pin OCn(2) Toggles the OCn(2) output line. Clears the OCn(2) output line (to zero). Sets the OCn(2) output line (to one).
1. In PWM mode, these bits have a different function. Refer to Table 24 for a detailed description. 2. n = 0 or 2
* Bit 3 - CTC0/CTC2: Clear Timer/Counter on Compare Match When the CTC0 or CTC2 control bit is set (one), Timer/Counter0 or Timer/Counter2 is reset to $00 in the CPU clock-cycle after a compare match. If the control bit is cleared, Timer/Counter continues counting and is unaffected by a compare match. When a prescaling of 1 is used, and the compare register is set to C, the timer will count as follows if CTC0/CTC2 is set: ... | C-1 | C | 0 | 1 | ... When the prescaler is set to divide by 8, the timer will count like this: ... | C-1, C-1, C-1, C-1, C-1, C-1, C-1, C-1 | C, C, C, C, C, C, C, C | 0, 0, 0, 0, 0, 0, 0, 0 | 1, 1, 1, ... In PWM mode, this bit has a different function. If the CTC0 or CTC2 bit is cleared in PWM mode, the Timer/Counter acts as an up/down counter. If the CTC0 or CTC2 bit is set (one), the Timer/Counter wraps when it reaches $FF. Refer to page 91 for a detailed description. * Bits 2,1,0 - CS02, CS01, CS00/ CS22, CS21, CS20: Clock Select Bits 2,1 and 0 The Clock Select bits 2,1 and 0 define the prescaling source of Timer/Counter0 and Timer/Counter2, see Table 22 and Table 23.
Table 22. Clock 0 Prescale Select
CS02 0 0 0 0 1 1 1 1 CS01 0 0 1 1 0 0 1 1 CS00 0 1 0 1 0 1 0 1 Description Stop, the Timer/Counter0 is stopped CK CK/8 CK/64 CK/256 CK/1024 External pin PE0(T0), falling edge External pin PE0(T0), rising edge
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Table 23. Clock 2 Prescale Select
CS22 0 0 0 0 1 1 1 1 CS21 0 0 1 1 0 0 1 1 CS20 0 1 0 1 0 1 0 1 Description Stop, the Timer/Counter2 is stopped PCK2 PCK2/8 PCK2/32 PCK2/64 PCK2/128 PCK2/256 PCK2/1024
The Stop condition provides a Timer Enable/Disable function. The prescaled modes are scaled directly from the CK oscillator clock for Timer/Counter0 and PCK2 for Timer/Counter2. If the external pin modes are used for Timer/Counter0, transitions on PE0/(T0) will clock the counter even if the pin is configured as an output. This feature can give the user SW control of the counting.
Timer Counter0 - TCNT0
Bit $32 ($52) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 TCNT0
Timer/Counter2 - TCNT2
Bit $23 ($43) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 TCNT2
These 8-bit registers contain the value of the Timer/Counters. Both Timer/Counters are realized as up or up/down (in PWM mode) counters with read and write access. If the Timer/Counter is written to and a clock source is selected, it continues counting in the timer clock cycle following the write operation.
Timer/Counter0 Output Compare Register - OCR0
Bit $31 ($51) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 OCR0
Timer/Counter2 Output Compare Register - OCR2
Bit $22 ($42) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 OCR2
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AT94K Series FPSLIC
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AT94K Series FPSLIC
The output compare registers are 8-bit read/write registers. The Timer/Counter Output Compare Registers contains the data to be continuously compared with the Timer/Counter. Actions on compare matches are specified in TCCR0 and TCCR2. A compare match does only occur if the Timer/Counter counts to the OCR value. A software write that sets Timer/Counter and Output Compare Register to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock-cycle following the compare event. Timer/Counter 0 and 2 in PWM Mode When PWM mode is selected, the Timer/Counter either wraps (overflows) when it reaches $FF or it acts as an up/down counter. If the up/down mode is selected, the Timer/Counter and the Output Compare Registers - OCR0 or OCR2 form an 8-bit, free-running, glitch-free and phase correct PWM with outputs on the PE1(OC0/PWM0) or PE3(OC2/PWM2) pin. If the overflow mode is selected, the Timer/Counter and the Output Compare Registers - OCR0 or OCR2 form an 8-bit, free-running and glitch-free PWM, operating with twice the speed of the up/down counting mode. PWM Modes (Up/Down and Overflow) The two different PWM modes are selected by the CTC0 or CTC2 bit in the Timer/Counter Control Registers - TCCR0 or TCCR2 respectively. If CTC0/CTC2 is cleared and PWM mode is selected, the Timer/Counter acts as an up/down counter, counting up from $00 to $FF, where it turns and counts down again to zero before the cycle is repeated. When the counter value matches the contents of the Output Compare Register, the PE1(OC0/PWM0) or PE3(OC2/PWM2) pin is set or cleared according to the settings of the COMn1/COMn0 bits in the Timer/Counter Control Registers TCCR0 or TCCR2. If CTC0/CTC2 is set and PWM mode is selected, the Timer/Counters will wrap and start counting from $00 after reaching $FF. The PE1(OC0/PWM0) or PE3(OC2/PWM2) pin will be set or cleared according to the settings of COMn1/COMn0 on a Timer/Counter overflow or when the counter value matches the contents of the Output Compare Register. Refer to Table 24 for details. Table 24. Compare Mode Select in PWM Mode
CTCn(1) x
(2)
COMn1(1) 0 1
COMn0(1) x
(2)
Effect on Compare Pin Not connected Cleared on compare match, up-counting. Set on compare match, down-counting (noninverted PWM) Cleared on compare match, down-counting. Set on compare match, up-counting (inverted PWM) Cleared on compare match, set on overflow Set on compare match, set on overflow
Frequency
- fTCK0/2/510
0
1
0
1
1
fTCK0/2/510
1 1 Notes:
1 1 1. n = 0 or 2 2. x = don' t care
0 1
fTCK0/2/256 fTCK0/2/256
In PWM mode, the value to be written to the Output Compare Register is first transferred to a temporary location, and then latched into the OCR when the Timer/Counter reaches $FF. This prevents the occurrence of odd-length PWM pulses (glitches) in the event of an unsynchronized OCR0 or OCR2 write. See Figure 52 and Figure 53 for examples.
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Figure 52. Effects of Unsynchronized OCR Latching in Up/Down Mode
Compare Value Changes Counter Value Compare Value PWM Output OCn(1) Synchronized OCn Compare Value Changes Counter Value Compare Value PWM Output OCn(1) Unsynchronized OCn
Note: 1. n = 0 or 2
(1) (1)
Latch
Latch
Glitch
Figure 53. Effects of Unsynchronized OCR Latching in Overflow Mode.
Compare Value Changes Counter Value Compare Value PWM Output OCn(1) Synchronized OCn
(1)
Latch Compare Value Changes Counter Value Compare Value PWM Output OCn(1)
Unsynchronized OCn(1) Latch
Note: 1. n = 0 or 2
Glitch
During the time between the write and the latch operation, a read from the Output Compare Registers will read the contents of the temporary location. This means that the most recently written value always will read out of OCR0 and OCR2. When the Output Compare Register contains $00 or $FF, and the up/down PWM mode is selected, the output PE1(OC0/PWM0)/PE3(OC2/PWM2) is updated to Low or High on the next compare match according to the settings of COMn1/COMn0. This is shown in Table 25. In overflow PWM mode, the output PE1(OC0/PWM0)/PE3(OC2/PWM2) is held Low or High only when the Output Compare Register contains $FF.
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Table 25. PWM Outputs OCRn = $00 or $FF(1)
COMn1(2) 1 1 1 1 Notes: COMn0(2) 0 0 1 1 OCRn(2) $00 $FF $00 $FF Output PWMn(2) L H H L
1. n overflow PWM mode, this table is only valid for OCRn = $FF 2. n = 0 or 2
In up/down PWM mode, the Timer Overflow Flag, TOV0 or TOV2, is set when the counter advances from $00. In overflow PWM mode, the Timer Overflow Flag is set as in normal Timer/Counter mode. Timer Overflow Interrupts 0 and 2 operate exactly as in normal Timer/Counter mode, i.e. they are executed when TOV0 or TOV2 are set provided that Timer Overflow Interrupt and global interrupts are enabled. This does also apply to the Timer Output Compare flag and interrupt.
Asynchronous Status Register - ASSR
Bit $26 ($46) Read/Write Initial Value 7 R 0 6 R 0 5 R 0 4 R 0 3 AS2 R/W 0 2 TCN2UB R 0 1 OCR2UB R 0 0 TCR2UB R 0 ASSR
* Bit 7..4 - Res: Reserved Bits These bits are reserved bits in the FPSLIC and are always read as zero. * Bit 3 - AS2: Asynchronous Timer/Counter2 Mode When this bit is cleared (zero) Timer/Counter2 is clocked from the internal system clock, CK. If AS2 is set, the Timer/Counter2 is clocked from the TOSC1 pin. When the value of this bit is changed the contents of TCNT2, OCR2 and TCCR2 might get corrupted. * Bit 2 - TCN2UB: Timer/Counter2 Update Busy When Timer/Counter2 operates asynchronously and TCNT2 is written, this bit becomes set (one). When TCNT2 has been updated from the temporary storage register, this bit is cleared (zero) by the hardware. A logic 0 in this bit indicates that TCNT2 is ready to be updated with a new value. * Bit 1 - OCR2UB: Output Compare Register2 Update Busy When Timer/Counter2 operates asynchronously and OCR2 is written, this bit becomes set (one). When OCR2 has been updated from the temporary storage register, this bit is cleared (zero) by the hardware. A logic 0 in this bit indicates that OCR2 is ready to be updated with a new value. * Bit 0 - TCR2UB: Timer/Counter Control Register2 Update Busy When Timer/Counter2 operates asynchronously and TCCR2 is written, this bit becomes set (one). When TCCR2 has been updated from the temporary storage register, this bit is cleared (zero) by the hardware. A logic 0 in this bit indicates that TCCR2 is ready to be updated with a new value. If a write is performed to any of the three Timer/Counter2 registers while its update busy flag is set (one), the updated value might get corrupted and cause an unintentional interrupt to occur.
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The mechanisms for reading TCNT2, OCR2 and TCCR2 are different. When reading TCNT2, the actual timer value is read. When reading OCR2 or TCCR2, the value in the temporary storage register is read. Asynchronous Operation of Timer/Counter2 When Timer/Counter2 operates asynchronously, some considerations must be taken: * When switching between asynchronous and synchronous clocking of Timer/Counter2, the timer registers TCNT2, OCR2 and TCCR2 might get corrupted. A safe procedure for switching the clock source is: 1. Disable the Timer/Counter2 interrupts by clearing OCIE2 and TOIE2. 2. Select clock source by setting AS2 as appropriate. 3. Write new values to TCNT2, OCR2 and TCCR2. 4. To switch to asynchronous operation: Wait for TCN2UB, OCR2UB, and TCR2UB. 5. Enable interrupts, if needed. * The oscillator is optimized for use with a 32.768 kHz watch crystal. An external clock signal applied to this pin goes through the same amplifier having a bandwidth of 256 kHz. The external clock signal should therefore be in the interval 0 Hz - 1 MHz. The frequency of the clock signal applied to the TOSC1 pin must be lower than one fourth of the CPU main clock frequency. When writing to one of the registers TCNT2, OCR2, or TCCR2, the value is transferred to a temporary register, and latched after two positive edges on TOSC1. The user should not write a new value before the contents of the temporary register have been transferred to its destination. Each of the three mentioned registers have their individual temporary register, which means that, e.g., writing to TCNT2 does not disturb an OCR2 write in progress. To detect that a transfer to the destination register has taken place, an Asynchronous Status Register - ASSR has been implemented. When entering Power-save mode after having written to TCNT2, OCR2, or TCCR2, the user must wait until the written register has been updated if Timer/Counter2 is used to wake-up the device. Otherwise, the MCU will go to sleep before the changes have had any effect. This is extremely important if the Output Compare2 interrupt is used to wake-up the device; Output compare is disabled during write to OCR2 or TCNT2. If the write cycle is not finished (i.e., the MCU enters Sleep mode before the OCR2UB bit returns to zero), the device will never get a compare match and the MCU will not wake-up. If Timer/Counter2 is used to wake-up the device from Power-save mode, precautions must be taken if the user wants to re-enter Power-save mode: The interrupt logic needs one TOSC1 cycle to be reset. If the time between wake-up and reentering Power-save mode is less than one TOSC1 cycle, the interrupt will not occur and the device will fail to wake up. If the user is in doubt whether the time before re-entering power-save is sufficient, the following algorithm can be used to ensure that one TOSC1 cycle has elapsed: 1. Write a value to TCCR2, TCNT2, or OCR2. 2. Wait until the corresponding Update Busy flag in ASSR returns to zero. 3. Enter Power-save mode. * When asynchronous operation is selected, the 32.768 kHz oscillator for Timer/Counter2 is always running, except in Power-down mode. After a power-up reset or wake-up from power-down, the user should be aware of the fact that this oscillator might take as long as one second to stabilize. Therefore, the contents of all Timer2 registers must be considered lost after a wake-up from power-down, due to the unstable clock signal. The user is advised to wait for at least one second before using Timer/Counter2 after power-up or wake-up from power-down. Description of wake-up from Power-save mode when the timer is clocked asynchronously. When the interrupt condition is met, the wake-up process is started on the following cycle
*
*
*
*
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of the timer clock, that is, the timer is always advanced by at least one before the processor can read the counter value. The interrupt flags are updated three processor cycles after the processor clock has started. During these cycles, the processor executes instructions, but the interrupt condition is not readable, and the interrupt routine has not started yet. * During asynchronous operation, the synchronization of the interrupt flags for the asynchronous timer takes three processor cycles plus one timer cycle. The timer is therefore advanced by at least one before the processor can read the timer value causing the setting of the interrupt flag. The output compare pin is changed on the timer clock and is not synchronized to the processor clock.
Timer/Counter1
Figure 54 shows the block diagram for Timer/Counter1.
Figure 54. Timer/Counter1 Block Diagram
T/C1 OVERFLOW IRQ T/C1 COMPARE MATCHA IRQ T/C1 COMPARE MATCHB IRQ T/C1 INPUT CAPTURE IRQ
8-BIT DATA BUS
OCIE1A
OCIE1B
OCF1A
OCF1B
TICIE1
OCIE2
TOIE1
TOIE2
OCIE0
TOIE0
OCF2
TOV1
TOV2
TIMER INT. MASK REGISTER (TIMSK)
TOV1
TIMER INT. FLAG REGISTER (TIFR)
OCF2 OCF1A OCF1B OCF0 ICF1 TOV2 TOV0
OCF0
ICF1
TOV0
T/C1 CONTROL REGISTER A (TCCR1A)
FOC1A
FOC1B
T/C1 CONTROL REGISTER B (TCCR1B)
ICNC1 CTC1 CS12 CS11 ICES1 CS10
SPECIAL FUNCTIONS IO REGISTER (SFIOR)
PSR2 PSR10
PWM11
COM1A1
COM1A0
COM1B0
15
8
7
0 CONTROL LOGIC CK T1
T/C1 INPUT CAPTURE REGISTER (ICR1)
CAPTURE TRIGGER
15
8
7
0
T/C CLEAR T/C CLOCK SOURCE UP/DOWN
TIMER/COUNTER1 (TCNT1)
15
8
7
0
15
COM1B1
PWM10
8
7
0
16 BIT COMPARATOR
16 BIT COMPARATOR
15
8
7
0
15
8
7
0
TIMER/COUNTER1 OUTPUT COMPARE REGISTER A
TIMER/COUNTER1 OUTPUT COMPARE REGISTER B
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The 16-bit Timer/Counter1 can select the clock source from CK, prescaled CK, or an external pin. In addition it can be stopped as described in section "Timer/Counter1 Control Register B - TCCR1B" on page 98. The different status flags (overflow, compare match and capture event) are found in the Timer/Counter Interrupt Flag Register - TIFR. Control signals are found in the Timer/Counter1 Control Registers - TCCR1A and TCCR1B. The interrupt enable/disable settings for Timer/Counter1 are found in the Timer/Counter Interrupt Mask Register - TIMSK. When Timer/Counter1 is externally clocked, the external signal is synchronized with the oscillator frequency of the CPU. To assure proper sampling of the external clock, the minimum time between two external clock transitions must be at least one internal CPU clock period. The external clock signal is sampled on the rising edge of the internal CPU clock. The 16-bit Timer/Counter1 features both a high-resolution and a high-accuracy usage with the lower prescaling opportunities. Similarly, the high-prescaling opportunities makes the Timer/Counter1 useful for lower speed functions or exact-timing functions with infrequent actions. The Timer/Counter1 supports two Output Compare functions using the Output Compare Register 1 A and B - OCR1A and OCR1B as the data sources to be compared to the Timer/Counter1 contents. The Output Compare functions include optional clearing of the counter on compareA match, and actions on the Output Compare pins on both compare matches. Timer/Counter1 can also be used as a 8-, 9- or 10-bit Pulse Width Modulator. In this mode, the counter and the OCR1A/OCR1B registers serve as a dual-glitch-free stand-alone PWM with centered pulses. Alternatively, the Timer/Counter1 can be configured to operate at twice the speed in PWM mode, but without centered pulses. Refer to page 101 for a detailed description on this function. The Input Capture function of Timer/Counter1 provides a capture of the Timer/Counter1 contents to the Input Capture Register - ICR1, triggered by an external event on the Input Capture Pin - PE7(ICP). The actual capture event settings are defined by the Timer/Counter1 Control Register - TCCR1B. Figure 55. ICP Pin Schematic Diagram
ICPE
ICPE: Input Capture Pin Enable
If the noise canceler function is enabled, the actual trigger condition for the capture event is monitored over four samples, and all four must be equal to activate the capture flag.
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Timer/Counter1 Control Register A - TCCR1A
Bit $2F ($4F) Read/Write Initial Value
7 COM1A1 R/W 0 6 COM1A0 R/W 0 5 COM1B1 R/W 0 4 COM1B0 R/W 0 3 FOC1A R/w 0 2 FOC1B R/W 0 1 PWM11 R/W 0 0 PWM10 R/W 0 TCCR1A
* Bits 7,6 - COM1A1, COM1A0: Compare Output Mode1A, Bits 1 and 0 The COM1A1 and COM1A0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1A - Output CompareA pin PE6. This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. The control configuration is shown in Table 26. * Bits 5,4 - COM1B1, COM1B0: Compare Output Mode1B, Bits 1 and 0 The COM1B1 and COM1B0 control bits determine any output pin action following a compare match in Timer/Counter1. Any output pin actions affect pin OC1B - Output CompareB pin PE5. This is an alternative function to an I/O port, and the corresponding direction control bit must be set (one) to control an output pin. The following control configuration is given: Table 26. Compare 1 Mode Select(1)
COM1X1(2) 0 0 1 1 Notes: COM1X0(2) 0 1 0 1 Description Timer/Counter1 disconnected from output pin OC1X Toggles the OC1X output line Clears the OC1X output line (to zero) Sets the OC1X output line (to one)
1. In PWM mode, these bits have a different function. Refer to Table 30 for a detailed description. 2. X = A or B
* Bit 3 - FOC1A: Force Output Compare1A Writing a logic 1 to this bit forces a change in the compare match output pin PE6 according to the values already set in COM1A1 and COM1A0. If the COM1A1 and COM1A0 bits are written in the same cycle as FOC1A, the new settings will not take effect until next compare match or forced compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COM1A1 and COM1A0 happens as if a Compare Match had occurred, but no interrupt is generated and it will not clear the timer even if CTC1 in TCCR1B is set. The FOC1A bit will always be read as zero. The setting of the FOC1A bit has no effect in PWM mode. * Bit 2 - FOC1B: Force Output Compare1B Writing a logic 1 to this bit forces a change in the compare match output pin PE5 according to the values already set in COM1B1 and COM1B0. If the COM1B1 and COM1B0 bits are written in the same cycle as FOC1B, the new settings will not take effect until next compare match or forced compare match occurs. The Force Output Compare bit can be used to change the output pin without waiting for a compare match in the timer. The automatic action programmed in COM1B1 and COM1B0 happens as if a Compare Match had occurred, but no interrupt is generated. The FOC1B bit will always be read as zero. The setting of the FOC1B bit has no effect in PWM mode.
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* Bits 1..0 - PWM11, PWM10: Pulse Width Modulator Select Bits These bits select PWM operation of Timer/Counter1 as specified in Table 27. This mode is described on page 101. Table 27. PWM Mode Select
PWM11 0 0 1 1 PWM10 0 1 0 1 Description PWM operation of Timer/Counter1 is disabled Timer/Counter1 is an 8-bit PWM Timer/Counter1 is a 9-bit PWM Timer/Counter1 is a 10-bit PWM
Timer/Counter1 Control Register B - TCCR1B
Bit $2E ($4E) Read/Write Initial Value 7 ICNC1 R/W 0 6 ICES1 R/W 0 5 ICPE R/W 0 4 R 0 3 CTC1 R/W 0 2 CS12 R/W 0 1 CS11 R/W 0 0 CS10 R/W 0 TCCR1B
* Bit 7 - ICNC1: Input Capture1 Noise Canceler (4 CKs) When the ICNC1 bit is cleared (zero), the input capture trigger noise canceler function is disabled. The input capture is triggered at the first rising/falling edge sampled on the PE7(ICP) - input capture pin - as specified. When the ICNC1 bit is set (one), four successive samples are measures on the PE7(ICP) - input capture pin, and all samples must be High/Low according to the input capture trigger specification in the ICES1 bit. The actual sampling frequency is XTAL clock frequency. * Bit 6 - ICES1: Input Capture1 Edge Select While the ICES1 bit is cleared (zero), the Timer/Counter1 contents are transferred to the Input Capture Register - ICR1 - on the falling edge of the input capture pin - PE7(ICP). While the ICES1 bit is set (one), the Timer/Counter1 contents are transferred to the Input Capture Register - ICR1 - on the rising edge of the input capture pin - PE7(ICP). * Bit 5 - ICPE: Input Captive Pin Enable This bit must be set by the user to enable the Input Capture Function of timer1. Disabling prevents unnecessary register copies during normal use of the PE7 port. * Bit 4 - Res: Reserved Bit This bit is reserved in the FPSLIC and will always read zero. * Bit 3 - CTC1: Clear Timer/Counter1 on Compare Match When the CTC1 control bit is set (one), the Timer/Counter1 is reset to $0000 in the clock cycle after a compareA match. If the CTC1 control bit is cleared, Timer/Counter1 continues counting and is unaffected by a compare match. When a prescaling of 1 is used, and the compareA register is set to C, the timer will count as follows if CTC1 is set: ... | C-1 | C | 0 | 1 | ... When the prescaler is set to divide by 8, the timer will count like this: ... | C-1, C-1, C-1, C-1, C-1, C-1, C-1, C-1 | C, C, C, C, C, C, C, C | 0, 0, 0, 0, 0, 0, 0, 0 | ... In PWM mode, this bit has a different function. If the CTC1 bit is cleared in PWM mode, the Timer/Counter1 acts as an up/down counter. If the CTC1 bit is set (one), the Timer/Counter wraps when it reaches the TOP value. Refer to page 101 for a detailed description.
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* Bits 2,1,0 - CS12, CS11, CS10: Clock Select1, Bits 2, 1 and 0 The Clock Select1 bits 2,1 and 0 define the prescaling source of Timer/Counter1. Table 28. Clock 1 Prescale Select
CS12 0 0 0 0 1 1 1 1 CS11 0 0 1 1 0 0 1 1 CS10 0 1 0 1 0 1 0 1 Description Stop, the Timer/Counter1 is stopped CK CK/8 CK/64 CK/256 CK/1024 External pin PE4 (T1), falling edge External pin PE4 (T1), rising edge
The Stop condition provides a Timer Enable/Disable function. The CK down-divided modes are scaled directly from the CK oscillator clock. If the external pin modes are used for Timer/Counter1, transitions on PE4/(T1) will clock the counter even if the pin is configured as an output. This feature can give the user SW control of the counting.
Timer/Counter1 Register - TCNT1H AND TCNT1L
Bit $2D ($4D) $2C ($4C) 7 Read/Write Initial Value R/W R/W 0 0 6 R/W R/W 0 0 5 R/W R/W 0 0 4 R/W R/W 0 0 3 R/W R/W 0 0 2 R/W R/W 0 0 1 R/W R/W 0 0 15 MSB LSB 0 R/W R/W 0 0 14 13 12 11 10 9 8 TCNT1H TCNT1L
This 16-bit register contains the prescaled value of the 16-bit Timer/Counter1. To ensure that both the High and low bytes are read and written simultaneously when the CPU accesses these registers, the access is performed using an 8-bit temporary register (TEMP). This temporary register is also used when accessing OCR1A, OCR1B and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program and interrupt routines.
TCNT1 Timer/Counter1 Write
When the CPU writes to the high byte TCNT1H, the written data is placed in the TEMP register. Next, when the CPU writes the low byte TCNT1L, this byte of data is combined with the byte data in the TEMP register, and all 16 bits are written to the TCNT1 Timer/Counter1 register simultaneously. Consequently, the high byte TCNT1H must be accessed first for a full 16-bit register write operation.
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TCNT1 Timer/Counter1 Read
When the CPU reads the low byte TCNT1L, the data of the low byte TCNT1L is sent to the CPU and the data of the high byte TCNT1H is placed in the TEMP register. When the CPU reads the data in the high byte TCNT1H, the CPU receives the data in the TEMP register. Consequently, the low byte TCNT1L must be accessed first for a full 16-bit register read operation. The Timer/Counter1 is realized as an up or up/down (in PWM mode) counter with read and write a ccess . If Timer/Co un ter1 is w ritte n to a nd a clock sou rce is se le cted , th e Timer/Counter1 continues counting in the timer clock-cycle after it is preset with the written value.
Timer/Counter1 Output Compare Register - OCR1AH AND OCR1AL
Bit $2B ($4B) $2A ($4A) 7 Read/Write Initial Value R/W R/W 0 0 6 R/W R/W 0 0 5 R/W R/W 0 0 4 R/W R/W 0 0 3 R/W R/W 0 0 2 R/W R/W 0 0 1 R/W R/W 0 0 15
MSB LSB
14
13
12
11
10
9
8
OCR1AH OCR1AL
0 R/W R/W 0 0
Timer/Counter1 Output Compare Register - OCR1BH AND OCR1BL
Bit $29 ($49) $28 ($48) 7 Read/Write Initial Value R/W R/W 0 0 6 R/W R/W 0 0 5 R/W R/W 0 0 4 R/W R/W 0 0 3 R/W R/W 0 0 2 R/W R/W 0 0 1 R/W R/W 0 0 15 MSB LSB 0 R/W R/W 0 0 14 13 12 11 10 9 8 OCR1BH OCR1BL
The output compare registers are 16-bit read/write registers. The Timer/Counter1 Output Compare Registers contain the data to be continuously compared with Timer/Counter1. Actions on compare matches are specified in the Timer/Counter1 Control and Status register. A compare match does only occur if Timer/Counter1 counts to the OCR value. A software write that sets TCNT1 and OCR1A or OCR1B to the same value does not generate a compare match. A compare match will set the compare interrupt flag in the CPU clock cycle following the compare event. Since the Output Compare Registers - OCR1A and OCR1B - are 16-bit registers, a temporary register TEMP is used when OCR1A/B are written to ensure that both bytes are updated simultaneously. When the CPU writes the high byte, OCR1AH or OCR1BH, the data is temporarily stored in the TEMP register. When the CPU writes the low byte, OCR1AL or OCR1BL, the TEMP register is simultaneously written to OCR1AH or OCR1BH. Consequently, the high byte OCR1AH or OCR1BH must be written first for a full 16-bit register write operation. The TEMP register is also used when accessing TCNT1, and ICR1. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program and interrupt routines.
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Timer/Counter1 Input Capture Register - ICR1H AND ICR1L
Bit $25 ($45) $24 ($44) 7 Read/Write Initial Value R R 0 0 6 R R 0 0 5 R R 0 0 4 R R 0 0 3 R R 0 0 2 R R 0 0 1 R R 0 0 15 MSB LSB 0 R R 0 0 14 13 12 11 10 9 8 ICR1H ICR1L
The input capture register is a 16-bit read-only register. When the rising or falling edge (according to the input capture edge setting - ICES1) of the signal a t the input capture pin - PE7(ICP) - is detected , the current value of the Timer/Counter1 Register - TCNT1 is transferred to the Input Capture Register - ICR1. In the same cycle, the input capture flag - ICF1 - is set (one). Since the Input Capture Register - ICR1 - is a 16-bit register, a temporary register TEMP is used when ICR1 is read to ensure that both bytes are read simultaneously. When the CPU reads the low byte ICR1L, the data is sent to the CPU and the data of the high byte ICR1H is placed in the TEMP register. When the CPU reads the data in the high byte ICR1H, the CPU receives the data in the TEMP register. Consequently, the low byte ICR1L must be accessed first for a full 16-bit register read operation. The TEMP register is also used when accessing TCNT1, OCR1A and OCR1B. If the main program and also interrupt routines perform access to registers using TEMP, interrupts must be disabled during access from the main program and interrupt routine. Timer/Counter1 in PWM Mode When the PWM mode is selected, Timer/Counter1 and the Output Compare Register1A - OCR1A and the Output Compare Register1B - OCR1B, form a dual 8-, 9- or 10-bit, free-running, glitch-free and phase correct PWM with outputs on the PD6(OC1A) and PE5(OC1B) pins. In this mode the Timer/Counter1 acts as an up/down counter, counting up from $0000 to TOP (see Table 29), where it turns and counts down again to zero before the cycle is repeated. When the counter value matches the contents of the 8, 9 or 10 least significant bits (depends of the resolution) of OCR1A or OCR1B, the PD6(OC1A)/PE5(OC1B) pins are set or cleared according to the settings of the COM1A1/COM1A0 or COM1B1/COM1B0 bits in the Timer/Counter1 Control Register TCCR1A. Refer to Table 30 for details. Alternatively, the Timer/Counter1 can be configured to a PWM that operates at twice the speed as in the mode described above. Then the Timer/Counter1 and the Output Compare Register1A - OCR1A and the Output Compare Register1B - OCR1B, form a dual 8-, 9- or 10bit, free-running and glitch-free PWM with outputs on the PE6(OC1A) and PE5(OC1B) pins. As shown in Table 29, the PWM operates at either 8-, 9- or 10-bit resolution. Note the unused bits in OCR1A, OCR1B and TCNT1 will automatically be written to zero by the hardware. For example, bit 9 to 15 will be set to zero in OCR1A, OCR1B and TCNT1 if the 9-bit PWM resolution is selected. This makes it possible for the user to perform read-modify-write operations in any of the three resolution modes and the unused bits will be treated as "don't care".
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Table 29. Timer TOP Values and PWM Frequency
CTC1 0 0 0 1 1 1 PWM11 0 1 1 0 1 1 PWM10 1 0 1 1 0 1 PWM Resolution 8-bit 9-bit 10-bit 8-bit 9-bit 10-bit Timer TOP Value $00FF (255) $01FF (511) $03FF(1023) $00FF (255) $01FF (511) $03FF(1023) Frequency fTCK1/510 fTCK1/1022 fTCK1/2046 fTCK1/256 fTCK1/512 fTCK1/1024
Table 30. Compare1 Mode Select in PWM Mode
CTC1(1) x(2) 0 0 1 1 Notes: COM1X1(1) 0 1 1 1 1 1. X = A or B 2. x = Don't care COM1X0(1) x(2) 0 1 0 1 Effect on OCX1 Not connected Cleared on compare match, up-counting. Set on compare match, down-counting (non-inverted PWM) Cleared on compare match, down-counting. Set on compare match, up-counting (inverted PWM) Cleared on compare match, set on overflow Set on compare match, set on overflow
In the PWM mode, the 8, 9 or 10 least significant OCR1A/OCR1B bits (depends of resolution), when written, are transferred to a temporary location. They are latched when Timer/Counter1 reaches the value TOP. This prevents the occurrence of odd-length PWM pulses (glitches) in the event of an unsynchronized OCR1A/OCR1B write. See Figure 56 and Figure 57 for an example in each mode.
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Figure 56. Effects on Unsynchronized OCR1 Latching
Compare Value Changes
Counter Value Compare Value PWM OutputOC1X Synchronized
Compare Value Changes
(1)
OCR1X
(1)
Latch Counter Value Compare Value PWM OutputOC1X
(1)
Unsynchronized
Note: 1. X = A or B
OCR1X
(1)
Latch
Glitch
Figure 57. Effects of Unsynchronized OCR1 Latching in Overflow Mode
Compare Value Changes
PWM Output OC1x(1) Synchronized OC1x
(1)
Latch
Compare Value Changes
PWM Output OC1x(1) Unsynchronized OC1x(1) Latch
Note: 1. X = A or B
During the time between the write and the latch operation, a read from OCR1A or OCR1B will read the contents of the temporary location. This means that the most recently written value always will read out of OCR1A/B. When the OCR1X contains $0000 or TOP, and the up/down PWM mode is selected, the output OC1A/OC1B is updated to Low or High on the next compare match according to the settings of COM1A1/COM1A0 or COM1B1/COM1B0. This is shown in Table 31. In overflow PWM mode, the output OC1A/OC1B is held Low or High only when the Output Compare Register contains TOP.
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Table 31. PWM Outputs OCR1X = $0000 or TOP(1)
COM1X1(2) 1 1 1 1 Notes: COM1X0(2) 0 0 1 1 OCR1X(2) $0000 TOP $0000 TOP Output OC1X(2) L H H L
1. In overflow PWM mode, this table is only valid for OCR1X = TOP. 2. X = A or B
In up/down PWM mode, the Timer Overflow Flag1, TOV1, is set when the counter advances from $0 000 . In overflow PW M mo de , the Timer O verflo w fla g is se t a s in norma l Timer/Counter mode. Timer Overflow Interrupt1 operates exactly as in normal Timer/Counter mode, i.e., it is executed when TOV1 is set provided that Timer Overflow Interrupt1 and global interrupts are enabled. This also applies to the Timer Output Compare1 flags and interrupts.
Watchdog Timer
The Watchdog Timer is clocked from a separate on-chip oscillator which runs at 1 MHz. This is the typical value at VCC = 3.3V. See characterization data for typical values at other VCC levels. By controlling the Watchdog Timer prescaler, the watchdog reset interval can be adjusted, see Table 32 on page 105 for a detailed description. The WDR (watchdog reset) instruction resets the Watchdog Timer. Eight different clock cycle periods can be selected to determine the reset period. If the reset period expires without another watchdog reset, the FPSLIC resets and executes from the reset vector. To prevent unintentional disabling of the watchdog, a special turn-off sequence must be followed when the watchdog is disabled, see Figure 58. Figure 58. Watchdog Timer
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Watchdog Timer Control Register - WDTCR
Bit $21 ($41) Read/Write Initial Value 7 R 0 6 R 0 5 R 0 4 WDTOE R/W 0 3 WDE R/W 0 2 WDP2 R/W 0 1 WDP1 R/W 0 0 WDP0 R/W 0 WDTCR
* Bits 7..5 - Res: Reserved Bits These bits are reserved bits in the FPSLIC and will always read as zero. * Bit 4 - WDTOE: Watchdog Turn-off Enable This bit must be set (one) when the WDE bit is cleared. Otherwise, the watchdog will not be disabled. Once set, the hardware will clear this bit to zero after four clock cycles. Refer to the description of the WDE bit below for a watchdog disable procedure. * Bit 3 - WDE: Watchdog Enable When the WDE is set (one) the Watchdog Timer is enabled, but if the WDE is cleared (zero), the Watchdog Timer function is disabled. WDE can only be cleared if the WDTOE bit is set (one). To disable an enabled Watchdog Timer, the following procedure must be followed: 1. In the same operation, write a logic 1 to WDTOE and WDE. A logic 1 must be written to WDE even though it is set to one before the disable operation starts. 2. Within the next four clock cycles, write a logic 0 to WDE. This disables the watchdog. * Bits 2..0 - WDP2, WDP1, WDP0: Watchdog Timer Prescaler 2, 1 and 0 The WDP2, WDP1 and WDP0 bits determine the Watchdog Timer prescaling when the Watchdog Timer is enabled. The different prescaling values and their corresponding Time-out periods are shown in Table 32. Table 32. Watchdog Timer Prescale Select
WDP2 0 0 0 0 1 1 1 1 Note: WDP1 0 0 1 1 0 0 1 1 WDP0 0 1 0 1 0 1 0 1 Number of WDT Oscillator Cycles(1) 16K 32K 64K 128K 256K 512K 1,024K 2,048K Typical Time-out at VCC = 3.0V 47 ms 94 ms 0.19s 0.38s 0.75s 1.5s 3.0s 6.0s
1. The frequency of the watchdog oscillator is voltage dependent as shown in the Electrical Characteristics section. The WDR (watchdog reset) instruction should always be executed before the Watchdog Timer is enabled. This ensures that the reset period will be in accordance with the Watchdog Timer prescale settings. If the Watchdog Timer is enabled without reset, the Watchdog Timer may not start counting from zero.
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Multiplier
The multiplier is capable of multiplying two 8-bit numbers, giving a 16-bit result using only two clock cycles. The multiplier can handle both signed and unsigned integer and fractional numbers without speed or code size penalty. Below are some examples of using the multiplier for 8-bit arithmetic. To be able to use the multiplier, six new instructions are added to the AVR instruction set. These are: * * * * * * MUL, multiplication of unsigned integers MULS, multiplication of signed integers MULSU, multiplication of a signed integer with an unsigned integer FMUL, multiplication of unsigned fractional numbers FMULS, multiplication of signed fractional numbers FMULSU, multiplication of a signed fractional number and with an unsigned fractional number
The MULSU and FMULSU instructions are included to improve the speed and code density for multiplication of 16-bit operands. The second section will show examples of how to efficiently use the multiplier for 16-bit arithmetic. The component that makes a dedicated digital signal processor (DSP) specially suitable for signal processing is the multiply-accumulate (MAC) unit. This unit is functionally equivalent to a multiplier directly connected to an arithmetic logic unit (ALU). The FPSLIC-based AVR Core is designed to give FPSLIC the ability to effectively perform the same multiply-accumulate operation. The multiply-accumulate operation (sometimes referred to as multiply-add operation) has one critical drawback. When adding multiple values to one result variable, even when adding positive and negative values to some extent, cancel each other; the risk of the result variable to overrun its limits becomes evident, i.e. if adding 1 to a signed byte variable that contains the value +127, the result will be -128 instead of +128. One solution often used to solve this problem is to introduce fractional numbers, i.e. numbers that are less than 1 and greater than or equal to -1. Some issues regarding the use of fractional numbers are discussed. A list of all implementations with key performance specifications is given in Table 33. Table 33. Performance Summary
8-bit x 8-bit Routines: Unsigned Multiply 8 x 8 = 16 bits Signed Multiply 8 x 8 = 16 bits Fractional Signed/Unsigned Multiply 8 x 8 = 16 bits Fractional Signed Multiply-accumulate 8 x 8 + = 16 bits 16-bit x 16-bit Routines: Signed/Unsigned Multiply 16 x 16 = 32 bits UnSigned Multiply 16 x 16 = 32 bits Signed Multiply 16 x 16 = 32 bits Signed Multiply-accumulate 16 x 16 + = 32 bits Fractional Signed Multiply 16 x 16 = 32 bits Fractional Signed Multiply-accumulate 16 x 16 + = 32 bits Word (Cycles) 1 (2) 1 (2) 1 (2) 3 (4) Word (Cycles) 6 (9) 13 (17) 15 (19) 19 (23) 16 (20) 21 (25)
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8-bit Multiplication Doing an 8-bit multiply using the hardware multiplier is simple: just load the operands into two registers (or only one for square multiply) and execute one of the multiply instructions. The result will be placed in register pair R1:R0. However, note that only the MUL instruction does not have register usage restrictions. Figure 59 shows the valid (operand) register usage for each of the multiply instructions. The first example shows an assembly code that reads the port B input value and multiplies this value with a constant (5) before storing the result in register pair R17:R16.
in ldi mul movw r16,PINB r17,5 r16,r17 ; Read pin values ; Load 5 into r17 ; r1:r0 = r17 * r16 ; register pair
Example 1 - Basic Usage
r17:r16,r1:r0; Move the result to the r17:r16
Note the use of the MOVW instruction. This example is valid for all of the multiply instructions. Figure 59. Valid Register Usage
MUL
R0 R1 R2 R3 R4 R5 R6 R7 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31
MULS
MULSU FMUL FMULS FMULSU
R16 R17 R18 R19 R20 R21 R22 R23 R24 R25 R26 R27 R28 R29 R30 R31
R16 R17 R18 R19 R20 R21 R22 R23
Example 2 - Special Cases
This example shows some special cases of the MUL instruction that are valid.
lds lds mul lds mul r0,variableA; Load r0 with SRAM variable A r1,variableB; Load r1 with SRAM variable B r1,r0 ; r1:r0 = variable A * variable B
r0,variableA; Load r0 with SRAM variable A r0,r0 ; r0:r0 = square(variable A)
Even though the operand is put in the result register pair R1:R0, the operation gives the correct result since R1 and R0 are fetched in the first clock cycle and the result is stored back in the second clock cycle.
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Example 3 - Multiplyaccumulate Operation
The final example of 8-bit multiplication shows a multiply-accumulate operation. The general formula can be written as:
c( n ) = a ( n ) x b + c( n - 1 )
; r17:r16 = r18 * r19 + r17:r16 in ldi muls add adc r18,PINB ; Get the current pin value on port B r19,b r19,r18 r16,r0 r17,r1 ; Load constant b into r19 ; r1:r0 = variable A * variable B ; r17:r16 += r1:r0
Typical applications for the multiply-accumulate operation are FIR (Finite Impulse Response) and IIR (Infinite Impulse Response) filters, PID regulators and FFT (Fast Fourier Transform). For these applications the FMULS instruction is particularly useful. The main advantage of using the FMULS instruction instead of the MULS instruction is that the 16-bit result of the FMULS operation always may be approximated to a (well-defined) 8-bit format, see "Using Fractional Numbers" on page 111. 16-bit Multiplication The new multiply instructions are specifically designed to improve 16-bit multiplication. This section presents solutions for using the hardware multiplier to do multiplication with 16-bit operands. Figure 60 schematically illustrates the general algorithm for multiplying two 16-bit numbers with a 32-bit result (C = A * B). AH denotes the high byte and AL the low byte of the A operand. CMH denotes the middle high byte and CML the middle low byte of the result C. Equal notations are used for the remaining bytes. The algorithm is basic for all multiplication. All of the partial 16-bit results are shifted and added together. The sign extension is necessary for signed numbers only, but note that the carry propagation must still be done for unsigned numbers. Figure 60. 16-bit Multiplication, General Algorithm
AH AL
X
BH BL
(sign ext)
AL * BL
+ + + =
(sign ext) (sign ext)
AL * BH AH * BL
AH * BH
CH
CMH
CML
CL
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16-bit x 16-bit = 16-bit Operation This operation is valid for both unsigned and signed numbers, even though only the unsigned multiply instruction (MUL) is needed, see Figure 61. A mathematical explanation is given: When A and B are positive numbers, or at least one of them is zero, the algorithm is clearly correct, provided that the product C = A * B is less than 216 if the product is to be used as an unsigned number, or less than 215 if the product is to be used as a signed number. When both factors are negative, the two's complement notation is used: A = 216 - |A| and B = 216 - |B|: C = A * B = (216 - |A|) * (216 - |B|) = |A * B| + 232 - 216 * (|A| + |B|) Here we are only concerned with the 16 LSBs; the last part of this sum will be discarded and we will get the (correct) result C = |A * B|. Figure 61. 16-bit Multiplication, 16-bit Result
AH
AL
X
BH
BL
AL * BL
1 2 3
+ + =
AL * BH AH * BL
CH CL
When one factor is negative and one factor is positive, for example, A is negative and B is positive: C = A * B = (216 - |A|) * |B| = (216 * |B|) - |A * B| = (216 - |A * B|) + 216 * (|B| - 1) The MSBs will be discarded and the correct two's complement notation result will be C = 216 - |A * B|. The product must be in the range 0 C 216 - 1 if unsigned numbers are used, and in the range -215 C 215 - 1 if signed numbers are used. When doing integer multiplication in C language, this is how it is done. The algorithm can be expanded to do 32-bit multiplication with 32-bit result.
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16-bit x 16-bit = 32-bit Operation
Example 4 - Basic Usage 16-bit x 16-bit = 32-bit Integer Multiply
Below is an example of how to call the 16 x 16 = 32 multiply subroutine. This is also illustrated in Figure 62.
ldi R23,HIGH(672) ldi R22,LOW(672) ; Load the number 672 into r23:r22 ldi R21,HIGH(1844) ldi R20,LOW(1844); Load the number 1844 into r21:r20 callmul16x16_32 ; Call 16bits x 16bits = 32bits ; multiply routine
Figure 62. 16-bit Multiplication, 32-bit Result
AH
AL
(sign ext)
X
BH
BL
AL * BH AH * BL AL * BL
3 4 1+2
+ + =
(sign ext)
AH * BH
CH
CMH
CML
CL
The 32-bit result of the unsigned multiplication of 672 and 1844 will now be in the registers R19:R18:R17:R16. If "muls16x16_32" is called instead of "mul16x16_32", a signed multiplication will be executed. If "mul16x16_16" is called, the result will only be 16 bits long and will be stored in the register pair R17:R16. In this example, the 16-bit result will not be correct.
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16-bit Multiplyaccumulate Operation Figure 63. 16-bit Multiplication, 32-bit Accumulated Result
AH
AL
X
BH
BL
(sign ext)
AL * BL
+ + + + =
(sign ext) (sign ext)
AL * BH AH * BL
AH * BH CH
CMH CML
CL
( Old )
CH
CMH
CML
CL
( New )
Using Fractional Numbers
Unsigned 8-bit fractional numbers use a format where numbers in the range [0, 2> are allowed. Bits 6 - 0 represent the fraction and bit 7 represents the integer part (0 or 1), i.e. a 1.7 format. The FMUL instruction performs the same operation as the MUL instruction, except that the result is left-shifted 1 bit so that the high byte of the 2-byte result will have the same 1.7 format as the operands (instead of a 2.6 format). Note that if the product is equal to or higher than 2, the result will not be correct. To fully understand the format of the fractional numbers, a comparison with the integer number format is useful: Table 20 illustrates the two 8-bit unsigned numbers formats. Signed fractional numbers, like signed integers, use the familiar two's complement format. Numbers in the range [-1, 1> may be represented using this format. If the byte "1011 0010" is interpreted as an unsigned integer, it will be interpreted as 128 + 32 + 16 + 2 = 178. On the other hand, if it is interpreted as an unsigned fractional number, it will be interpreted as 1 + 0.25 + 0.125 + 0.015625 = 1.390625. If the byte is assumed to be a signed number, it will be interpreted as 178 - 256 = -122 (integer) or as 1.390625 - 2 = -0.609375 (fractional number).
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Table 34. Comparison of Integer and Fractional Formats
Bit Number 7 6 5 4 3 2 1 0 Unsigned Integer Bit Significance 27 = 128 26 = 64 25 = 32 24 = 16 23 = 8 22 = 4 21 = 2 20 = 1 Unsigned Fractional Number Bit Significance 20 = 1 2-1 = 0.5 2-2 = 0.25 2-3 = 0.125 2-4 = 0.0625 2-5 = 0.3125 2-6 = 0.015625 2-7 = 0.0078125
Using the FMUL, FMULS and FMULSU instructions should not be more complex than the MUL, MULS and MULSU instructions. However, one potential problem is to assign fractional variables right values in a simple way. The fraction 0.75 (= 0.5 + 0.25) will, for example, be "0110 0000" if 8 bits are used. To convert a positive fractional number in the range [0, 2> (for example 1.8125) to the format used in the AVR, the following algorithm, illustrated by an example, should be used: Is there a "1" in the number? Yes, 1.8125 is higher than or equal to 1. Byte is now "1xxx xxxx" Is there a "0.5" in the rest? 0.8125 / 0.5 = 1.625 Yes, 1.625 is higher than or equal to 1. Byte is now "11xx xxxx" Is there a "0.25" in the rest? 0.625 / 0.5 = 1.25 Yes, 1.25 is higher than or equal to 1. Byte is now "111x xxxx" Is there a "0.125" in the rest? 0.25 / 0.5 = 0.5 No, 0.5 is lower than 1. Byte is now "1110 xxxx" Is there a "0.0625" in the rest? 0.5 / 0.5 = 1 Yes, 1 is higher than or equal to 1. Byte is now "1110 1xxx" Since we do not have a rest, the remaining three bits will be zero, and the final result is "1110 1000", which is 1 + 0.5 + 0.25 + 0.0625 = 1.8125.
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To convert a negative fractional number, first add 2 to the number and then use the same algorithm as already shown. 16-bit fractional numbers use a format similar to that of 8-bit fractional numbers; the high 8 bits have the same format as the 8-bit format. The low 8 bits are only an increase of accuracy of the 8-bit format; while the 8-bit format has an accuracy of 2-8, the16-bit format has an accuracy of 2-16. Then again, the 32-bit fractional numbers are an increase of accuracy to the 16-bit fractional numbers. Note the important difference between integers and fractional numbers when extra byte(s) are used to store the number: while the accuracy of the numbers is increased when fractional numbers are used, the range of numbers that may be represented is extended when integers are used. As mentioned earlier, using signed fractional numbers in the range [-1, 1> has one main advantage to integers: when multiplying two numbers in the range [-1, 1>, the result will be in the range [-1, 1], and an approximation (the highest byte(s)) of the result may be stored in the same number of bytes as the factors, with one exception: when both factors are -1, the product should be 1, but since the number 1 cannot be represented using this number format, the FMULS instruction will instead place the number -1 in R1:R0. The user should therefore assure that at least one of the operands is not -1 when using the FMULS instruction. The 16-bit x 16-bit fractional multiply also has this restriction.
Example 5 - Basic Usage 8-bit x 8-bit = 16-bit Signed Fractional Multiply
This example shows an assembly code that reads the port E input value and multiplies this value with a fractional constant (-0.625) before storing the result in register pair R17:R16.
in ldi movw r16,PINE r17,$B0 ; Read pin values ; Load -0.625 into r17 ; r1:r0 = r17 * r16
fmuls r16,r17
r17:r16,r1:r0; Move the result to the r17:r16 ; register pair
Note that the usage of the FMULS (and FMUL) instructions is very similar to the usage of the MULS and MUL instructions.
Example 6 - Multiplyaccumulate Operation
The example below uses data from the ADC. The ADC should be configured so that the format of the ADC result is compatible with the fractional two's complement format. For the ATmega83/163, this means that the ADLAR bit in the ADMUX I/O register is set and a differential channel is used. The ADC result is normalized to one.
ldi r23,$62 ldi r22,$C0 ; Load highbyte of ; fraction 0.771484375 ; Load lowbyte of ; fraction 0.771484375 in in r20,ADCL r21,ADCH ; Get lowbyte of ADC conversion ; Get highbyte of ADC conversion ;Call routine for signed fractional ; multiply accumulate
callfmac16x16_32
The registers R19:R18:R17:R16 will be incremented with the result of the multiplication of 0.771484375 with the ADC conversion result. In this example, the ADC result is treated as a signed fraction number. We could also treat it as a signed integer and call it "mac16x16_32" instead of "fmac16x16_32". In this case, the 0.771484375 should be replaced with an integer.
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Implementations
mul16x16_16
Description Multiply of two 16-bit numbers with a 16-bit result. Usage R17:R16 = R23:R22 * R21:R20 Statistics Cycles: 9 + ret
Words: 6 + ret Register usage: R0, R1 and R16 to R23 (8 registers)(1)
Note: 1. Full orthogonality, i.e., any register pair can be used as long as the result and the two operands do not share register pairs. The routine is non-destructive to the operands.
mul movw mul add mul add ret r22, r20 r17:r16, r1:r0 r23, r20 r17, r0 r21, r22 r17, r0 ; bh * al ; ah * bl ; al * bl
mul16x16_16:
mul16x16_32
Description Unsigned multiply of two 16-bit numbers with a 32-bit result. Usage R19:R18:R17:R16 = R23:R22 * R21:R20 Statistics Cycles: 17 + ret
Words: 13 + ret Register usage: R0 to R2 and R16 to R23 (11 registers)(1)
Note: 1. Full orthogonality, i.e., any register pair can be used as long as the result and the two operands do not share register pairs. The routine is non-destructive to the operands.
clr mul movw mul movw mul add adc adc mul add adc adc ret r2 r23, r21 r19:r18, r1:r0 r22, r20 r17:r16, r1:r0 r23, r20 r17, r0 r18, r1 r19, r2 r21, r22 r17, r0 r18, r1 r19, r2 ; bh * al ; ah * bl ; al * bl ; ah * bh
mul16x16_32:
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muls16x16_32 Description Signed multiply of two 16-bit numbers with a 32-bit result. Usage R19:R18:R17:R16 = R23:R22 * R21:R20 Statistics Cycles: 19 + ret
Words: 15 + ret Register usage: R0 to R2 and R16 to R23 (11 registers)(1)
Note: 1. The routine is non-destructive to the operands.
clr muls movw mul movw r2 r23, r21 r19:r18, r1:r0 r22, r20 r17:r16, r1:r0 ; (signed)ah * bl ; Sign extend ; al * bl ; (signed)ah * (signed)bh muls16x16_32:
mulsu r23, r20 sbc add adc adc r19, r2 r17, r0 r18, r1 r19, r2
mulsu r21, r22 sbc add adc adc ret r19, r2 r17, r0 r18, r1 r19, r2
; (signed)bh * al ; Sign Extend
mac16x16_32
Description
Signed multiply-accumulate of two 16-bit numbers with a 32-bit result. Usage R19:R18:R17:R16 += R23:R22 * R21:R20
Statistics
Cycles: 23 + ret Words: 19 + ret Register usage: R0 to R2 and R16 to R23 (11 registers)
mac16x16_32: clr muls add adc mul add adc adc adc r2 r23, r21 r18, r0 r19, r1 r22, r20 r16, r0 r17, r1 r18, r2 r19, r2 ; al * bl ; (signed)ah * (signed)bh ; Register Usage Optimized
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mulsu r23, r20 sbc add adc adc r19, r2 r17, r0 r18, r1 r19, r2
; (signed)ah * bl
mulsu r21, r22 sbc add adc adc ret r19, r2 r17, r0 r18, r1 r19, r2
; (signed)bh * al ; Sign extend
mac16x16_32_method_B:
; uses two temporary registers (r4,r5), Speed / Size Optimized ; but reduces cycles/words by 1
clr muls movw mul
r2 r23, r21 r5:r4,r1:r0 r22, r20 ; al * bl ; (signed)ah * (signed)bh
add adc adc adc
r16, r0 r17, r1 r18, r4 r19, r5
mulsu r23, r20 sbc add adc adc r19, r2 r17, r0 r18, r1 r19, r2
; (signed)ah * bl ; Sign extend
mulsu r21, r22 sbc add adc adc r19, r2 r17, r0 r18, r1 r19, r2
; (signed)bh * al ; Sign extend
ret
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fmuls16x16_32 Description Signed fractional multiply of two 16-bit numbers with a 32-bit result. Usage R19:R18:R17:R16 = (R23:R22 * R21:R20) << 1 Statistics Cycles: 20 + ret
Words: 16 + ret Register usage: R0 to R2 and R16 to R23 (11 registers)(1)
Note: 1. The routine is non-destructive to the operands.
clr movw fmul adc movw fmulsu sbc add adc adc fmulsu sbc add adc adc ret r2 ; ( (signed)ah * (signed)bh ) << 1 ; ( al * bl ) << 1 r19:r18, r1:r0 r22, r20 r18, r2 r17:r16, r1:r0 r23, r20 r19, r2 r17, r0 r18, r1 r19, r2 r21, r22 r19, r2 r17, r0 r18, r1 r19, r2 ; ( (signed)bh * al ) << 1 ; Sign extend ; ( (signed)ah * bl ) << 1 ; Sign extend fmuls16x16_32: fmuls r23, r21
fmac16x16_32
Description Signed fractional multiply-accumulate of two 16-bit numbers with a 32-bit result. Usage R19:R18:R17:R16 += (R23:R22 * R21:R20) << 1 Statistics Cycles: 25 + ret
Words: 21 + ret Register usage: R0 to R2 and R16 to R23 (11 registers)
fmac16x16_32: clr r2 ; Register usage optimized
fmuls r23, r21 add adc fmul adc adc add r18, r0 r19, r1 r22, r20 r18, r2 r19, r2 r16, r0
; ( (signed)ah * (signed)bh ) << 1
; ( al * bl ) << 1
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adc adc adc fmulsu sbc add adc adc fmulsu sbc add adc adc ret
r17, r1 r18, r2 r19, r2 r23, r20 r19, r2 r17, r0 r18, r1 r19, r2 r21, r22 r19, r2 r17, r0 r18, r1 r19, r2 ; ( (signed)bh * al ) << 1 ; ( (signed)ah * bl ) << 1
fmac16x16_32_method_B
; uses two temporary registers (r4,r5), speed/Size optimized ; but reduces cycles/words by 2
clr
r2
fmuls r23, r21 movw fmul adc add adc adc adc fmulsu sbc add adc adc fmulsu sbc add adc adc ret r5:r4,r1:r0 r22, r20 r4, r2 r16, r0 r17, r1 r18, r4 r19, r5 r23, r20 r19, r2 r17, r0 r18, r1 r19, r2 r21, r22 r19, r2 r17, r0 r18, r1 r19, r2
; ( (signed)ah * (signed)bh ) << 1 ; ( al * bl ) << 1
; ( (signed)ah * bl ) << 1
; ( (signed)bh * al ) << 1
Comment on Implementations
All 16-bit x 16-bit = 32-bit functions implemented here start by clearing the R2 register, which is just used as a "dummy" register with the "add with carry" (ADC) and "subtract with carry" (SBC) operations. These operations do not alter the contents of the R2 register. If the R2 register is not used elsewhere in the code, it is not necessary to clear the R2 register each time these functions are called, but only once prior to the first call to one of the functions.
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UARTs
The FPSLIC features two full duplex (separate receive and transmit registers) Universal Asynchronous Receiver and Transmitter (UART). The main features are: * * * * * * * * * * Data Transmission Baud-rate Generator Generates any Baud-rate High Baud-rates at Low XTAL Frequencies 8 or 9 Bits Data Noise Filtering Overrun Detection Framing Error Detection False Start Bit Detection Three Separate Interrupts on TX Complete, TX Data Register Empty and RX Complete Multi-processor Communication Mode Double Speed UART Mode
A block schematic of the UART transmitter is shown in Figure 64. The two UARTs are identical and the functionality is described in general for the two UARTs. Figure 64. UART Transmitter(1)
DATA BUS
XTAL
BAUD RATE GENERATOR
BAUD x 16
/16
UART I/O DATA REGISTER (UDRn)
STORE UDRn SHIFT ENABLE
PIN CONTROL LOGIC
BAUD
CONTROL LOGIC
IDLE
10(11)-BIT TX SHIFT REGISTER
TXDn
PE0/ PE2
RXENn TXENn CHR9n RXB8n TXB8n
UART CONTROL AND STATUS REGISTER (UCSRnB)
RXCIEn TXCIEn UDRIEn
UART CONTROL AND STATUS REGISTER (UCSRnA)
UDREn TXCn
DATA BUS
TXCn IRQ
UDREn IRQ
Note:
1. n = 0, 1
U2Xn MPCMPn
TXCn UDREn FEn ORn
RXCn
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Data transmission is initiated by writing the data to be transmitted to the UART I/O Data Register, UDRn. Data is transferred from UDRn to the Transmit shift register when: * * A new character has been written to UDRn after the stop bit from the previous character has been shifted out. The shift register is loaded immediately. A new character has been written to UDRn before the stop bit from the previous character has been shifted out. The shift register is loaded when the stop bit of the character currently being transmitted has been shifted out.
If the 10(11)-bit Transmitter shift register is empty, data is transferred from UDRn to the shift register. At this time the UDREn (UART Data Register Empty) bit in the UART Control and Status Register, UCSRnA, is set. When this bit is set (one), the UART is ready to receive the next character. At the same time as the data is transferred from UDRn to the 10(11)-bit shift register, bit 0 of the shift register is cleared (start bit) and bit 9 or 10 is set (stop bit). If a 9-bit data word is selected (the CHR9n bit in the UART Control and Status Register, UCSRnB is set), the TXB8 bit in UCSRnB is transferred to bit 9 in the Transmit shift register. On the Baud-rate clock following the transfer operation to the shift register, the start bit is shifted out on the TXDn pin. Then follows the data, LSB first. When the stop bit has been shifted out, the shift register is loaded if any new data has been written to the UDRn during the transmission. During loading, UDREn is set. If there is no new data in the UDRn register to send when the stop bit is shifted out, the UDREn flag will remain set until UDRn is written again. When no new data has been written, and the stop bit has been present on TXDn for one bit length, the TX Complete flag, TXCn, in UCSRnA is set. The TXENn bit in UCSRnB enables the UART transmitter when set (one). When this bit is cleared (zero), the PE0 (UART0) or PE2 (UART1) pin can be used for general I/O. When TXENn is set, the UART Transmitter will be connected to PE0 (UART0) or PE2 (UART1), which is forced to be an output pin regardless of the setting of the DDE0 bit in DDRE (UART0) or DDE2 in DDRE (UART1).
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Data Reception Figure 65 shows a block diagram of the UART Receiver. Figure 65. UART Receiver(1)
DATA BUS
XTAL
BAUD RATE GENERATOR PIN CONTROL LOGIC
BAUD x 16
UART I/O DATA REGISTER (UDRn) /16
BAUD
STORE UDRn
PE1/ PE3
RXDn
DATA RECOVERY LOGIC
10(11)-BIT RX SHIFT REGISTER
RXENn TXENn
CHR9n RXB8n TXB8n
UART CONTROL AND STATUS REGISTER (UCSRnB)
RXCIEn TXCIEn UDRIEn
UART CONTROL AND STATUS REGISTER (UCSRnA)
RXCn
DATA BUS
RXCn IRQ
Note: 1. n = 0, 1
The receiver front-end logic samples the signal on the RXDn pin at a frequency 16 times the baud-rate. While the line is idle, one single sample of logic 0 will be interpreted as the falling edge of a start bit, and the start bit detection sequence is initiated. Let sample 1 denote the first zero-sample. Following the 1-to-0 transition, the receiver samples the RXDn pin at samples 8, 9 and 10. If two or more of these three samples are found to be logic 1s, the start bit is rejected as a noise spike and the receiver starts looking for the next 1-to-0 transition.
U2Xn MPCMPn
TXCn UDREn FEn ORn
RXCn
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If however, a valid start bit is detected, sampling of the data bits following the start bit is performed. These bits are also sampled at samples 8, 9 and 10. The logical value found in at least two of the three samples is taken as the bit value. All bits are shifted into the transmitter shift register as they are sampled. Sampling of an incoming character is shown in Figure 66. Note that the description above is not valid when the UART transmission speed is doubled. See "Double Speed Transmission" on page 128 for a detailed description. Figure 66. Sampling Received Data(1)
Note:
1. This figure is not valid when the UART speed is doubled. See "Double Speed Transmission" on page 128 for a detailed description.
When the stop bit enters the receiver, the majority of the three samples must be one to accept the stop bit. If two or more samples are logic 0s, the Framing Error (FEn) flag in the UART Control and Status Register (UCSRnA) is set. Before reading the UDRn register, the user should always check the FEn bit to detect Framing Errors. Whether or not a valid stop bit is detected at the end of a character reception cycle, the data is transferred to UDRn and the RXCn flag in UCSRnA is set. UDRn is in fact two physically separate registers, one for transmitted data and one for received data. When UDRn is read, the Receive Data register is accessed, and when UDRn is written, the Transmit Data register is accessed. If the 9-bit data word is selected (the CHR9n bit in the UART Control and Status Register, UCSRnB is set), the RXB8n bit in UCSRnB is loaded with bit 9 in the Transmit shift register when data is transferred to UDRn. If, after having received a character, the UDRn register has not been read since the last receive, the OverRun (ORn) flag in UCSRnB is set. This means that the last data byte shifted into to the shift register could not be transferred to UDRn and has been lost. The ORn bit is buffered, and is updated when the valid data byte in UDRn is read. Thus, the user should always check the ORn bit after reading the UDRn register in order to detect any overruns if the baud-rate is High or CPU load is High. When the RXEN bit in the UCSRnB register is cleared (zero), the receiver is disabled. This means that the PE1 (n=0) or PE3 (n=1) pin can be used as a general I/O pin. When RXENn is set, the UART Receiver will be connected to PE1 (UART0) or PE3 (UART1), which is forced to be an input pin regardless of the setting of the DDE1 in DDRE (UART0) or DDB2 bit in DDRB (UART1). When PE1 (UART0) or PE3 (UART1) is forced to input by the UART, the PORTE1 (UART0) or PORTE3 (UART1) bit can still be used to control the pull-up resistor on the pin. When the CHR9n bit in the UCSRnB register is set, transmitted and received characters are 9 bits long plus start and stop bits. The 9th data bit to be transmitted is the TXB8n bit in UCSRnB register. This bit must be set to the wanted value before a transmission is initiated by writing to the UDRn register. The 9th data bit received is the RXB8n bit in the UCSRnB register.
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Multi-processor Communication Mode The Multi-processor Communication Mode enables several Slave MCUs to receive data from a Master MCU. This is done by first decoding an address byte to find out which MCU has been addressed. If a particular Slave MCU has been addressed, it will receive the following data bytes as normal, while the other Slave MCUs will ignore the data bytes until another address byte is received. For an MCU to act as a Master MCU, it should enter 9-bit transmission mode (CHR9n in UCSRnB set). The 9-bit must be one to indicate that an address byte is being transmitted, and zero to indicate that a data byte is being transmitted. For the Slave MCUs, the mechanism appears slightly different for 8-bit and 9-bit Reception mode. In 8-bit Reception mode (CHR9n in UCSRnB cleared), the stop bit is one for an address byte and zero for a data byte. In 9-bit Reception mode (CHR9n in UCSRnB set), the 9-bit is one for an address byte and zero for a data byte, whereas the stop bit is always High. The following procedure should be used to exchange data in Multi-processor Communication mode: 1. All Slave MCUs are in Multi-processor Communication Mode (MPCMn in UCSRnA is set). 2. The Master MCU sends an address byte, and all Slaves receive and read this byte. In the Slave MCUs, the RXCn flag in UCSRnA will be set as normal. 3. Each Slave MCU reads the UDRn register and determines if it has been selected. If so, it clears the MPCMn bit in UCSRnA, otherwise it waits for the next address byte. 4. For each received data byte, the receiving MCU will set the receive complete flag (RXCn in UCSRnA. In 8-bit mode, the receiving MCU will also generate a framing error (FEn in UCSRnA set), since the stop bit is zero. The other Slave MCUs, which still have the MPCMn bit set, will ignore the data byte. In this case, the UDRn register and the RXCn, FEn, or flags will not be affected. 5. After the last byte has been transferred, the process repeats from step 2. UART Control
UART0 I/O Data Register - UDR0
Bit $0C ($2C) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 UDR0
UART1 I/O Data Register - UDR1
Bit $03 ($23) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 UDR1
The UDRn register is actually two physically separate registers sharing the same I/O address. When writing to the register, the UART Transmit Data register is written. When reading from UDRn, the UART Receive Data register is read.
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UART0 Control and Status Registers - UCSR0A
Bit $0B ($2B) Read/Write Initial Value 7 RXC0 R 0 6 TXC0 R/W 0 5 UDRE0 R 1 4 FE0 R 0 3 OR0 R 0 2 R 0 1 U2X0 R/W 0 0 MPCM0 R/W 0 UCSR0A
UART1 Control and Status Registers - UCSR1A
Bit $02 ($22) Read/Write Initial Value 7 RXC1 R 0 6 TXC1 R/W 0 5 UDRE1 R 1 4 FE1 R 0 3 OR1 R 0 2 R 0 1 U2X1 R/W 0 0 MPCM1 R/W 0 UCSR1A
* Bit 7 - RXC0/RXC1: UART Receive Complete This bit is set (one) when a received character is transferred from the Receiver Shift register to UDRn. The bit is set regardless of any detected framing errors. When the RXCIEn bit in UCSRnB is set, the UART Receive Complete interrupt will be executed when RXCn is set (one). RXCn is cleared by reading UDRn. When interrupt-driven data reception is used, the UART Receive Complete Interrupt routine must read UDRn in order to clear RXCn, otherwise a new interrupt will occur once the interrupt routine terminates. * Bit 6 - TXC0/TXC1: UART Transmit Complete This bit is set (one) when the entire character (including the stop bit) in the Transmit Shift register has been shifted out and no new data has been written to UDRn. This flag is especially useful in half-duplex communications interfaces, where a transmitting application must enter receive mo de and free the communicatio ns bu s immediately after completing the transmission. When the TXCIEn bit in UCSRnB is set, setting of TXCn causes the UART Transmit Complete interrupt to be executed. TXCn is cleared by the hardware when executing the corresponding interrupt handling vector. Alternatively, the TXCn bit is cleared (zero) by writing a logic 1 to the bit. * Bit 5 - UDRE0/UDRE1: UART Data Register Empty This bit is set (one) when a character written to UDRn is transferred to the Transmit shift register. Setting of this bit indicates that the transmitter is ready to receive a new character for transmission. When the UDRIEn bit in UCSRnB is set, the UART Transmit Complete interrupt will be executed as long as UDREn is set and the global interrupt enable bit in SREG is set. UDREn is cleared by writing UDRn. When interrupt-driven data transmittal is used, the UART Data Register Empty Interrupt routine must write UDRn in order to clear UDREn, otherwise a new interrupt will occur once the interrupt routine terminates. UDREn is set (one) during reset to indicate that the transmitter is ready. * Bit 4 - FE0/FE1: Framing Error This bit is set if a Framing Error condition is detected, i.e., when the stop bit of an incoming character is zero. The FEn bit is cleared when the stop bit of received data is one.
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* Bit 3 - OR0/OR1: OverRun This bit is set if an Overrun condition is detected, i.e., when a character already present in the UDRn register is not read before the next character has been shifted into the Receiver Shift register. The ORn bit is buffered, which means that it will be set once the valid data still in UDRn is read. The ORn bit is cleared (zero) when data is received and transferred to UDRn. * Bit 2 - Res: Reserved Bit This bit is reserved in the AT94K and will always read as zero. * Bits 1 - U2X0/U2X1: Double the UART Transmission Speed When this bit is set (one) the UART speed will be doubled. This means that a bit will be transmitted/received in eight CPU clock periods instead of 16 CPU clock periods. For a detailed description, see "Double Speed Transmission" on page 128". * Bit 0 - MPCM0/MPCM1: Multi-processor Communication Mode This bit is used to enter Multi-processor Communication Mode. The bit is set when the Slave MCU waits for an address byte to be received. When the MCU has been addressed, the MCU switches off the MPCMn bit, and starts data reception. For a detailed description, see "Multi-processor Communication Mode" on page 123.
UART0 Control and Status Registers - UCSR0B
Bit $0A ($2A) Read/Write Initial Value 7 RXCIE0 R/W 0 6 TXCIE0 R/W 0 5 UDRIE0 R/W 0 4 RXEN0 R/W 0 3 TXEN0 R/W 0 2 CHR90 R/W 0 1 RXB80 R 1 0 TXB80 R/W 0 UCSR0B
UART1 Control and Status Registers - UCSR1B
Bit $01 ($21) Read/Write Initial Value 7 RXCIE1 R/W 0 6 TXCIE1 R/W 0 5 UDRIE1 R/W 0 4 RXEN1 R/W 0 3 TXEN1 R/W 0 2 CHR91 R/W 0 1 RXB81 R 1 0 TXB81 R/W 0 UCSR1B
* Bit 7 - RXCIE0/RXCIE1: RX Complete Interrupt Enable When this bit is set (one), a setting of the RXCn bit in UCSRnA will cause the Receive Complete interrupt routine to be executed provided that global interrupts are enabled. * Bit 6 - TXCIE0/TXCIE1: TX Complete Interrupt Enable When this bit is set (one), a setting of the TXCn bit in UCSRnA will cause the Transmit Complete interrupt routine to be executed provided that global interrupts are enabled. * Bit 5 - UDRIE0/UDREI1: UART Data Register Empty Interrupt Enable When this bit is set (one), a setting of the UDREn bit in UCSRnA will cause the UART Data Register Empty interrupt routine to be executed provided that global interrupts are enabled. * Bit 4 - RXEN0/RXEN1: Receiver Enable This bit enables the UART receiver when set (one). When the receiver is disabled, the TXCn, ORn and FEn status flags cannot become set. If these flags are set, turning off RXENn does not cause them to be cleared.
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* Bit 3 - TXEN0/TXEN1: Transmitter Enable This bit enables the UART transmitter when set (one). When disabling the transmitter while transmitting a character, the transmitter is not disabled before the character in the shift register plus any following character in UDRn has been completely transmitted. * Bit 2 - CHR90/CHR91: 9-bit Characters When this bit is set (one) transmitted and received characters are 9-bit long plus start and stop bits. The 9-bit is read and written by using the RXB8n and TXB8n bits in UCSRnB, respectively. The 9th data bit can be used as an extra stop bit or a parity bit. * Bit 1 - RXB80/RXB81: Receive Data Bit 8 When CHR9n is set (one), RXB8n is the 9th data bit of the received character. * Bit 0 - TXB80/TXB81: Transmit Data Bit 8 When CHR9n is set (one), TXB8n is the 9th data bit in the character to be transmitted. Baud-rate Generator The baud-rate generator is a frequency divider which generates baud-rates according to the following equation(1):
f CK BAUD = --------------------------------16(UBR + 1 )
* * * BAUD = Baud-rate fCK = Crystal Clock Frequency UBR = Contents of the UBRRHI and UBRRn Registers, (0 - 4095)
1. This equation is not valid when the UART transmission speed is doubled. See "Double Speed Transmission" on page 128 for a detailed description.
Note:
For standard crystal frequencies, the most commonly used baud-rates can be generated by using the UBR settings in Table 35. UBR values which yield an actual baud-rate differing less than 2% from the target baud-rate, are bold in the table. However, using baud-rates that have more than 1% error is not recommended. High error ratings give less noise resistance.
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Table 35. UBR Settings at Various Crystal Frequencies
Clock MHz UBRRHI 7:4 or 3:0 1 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 UBRRn 00011001 00001100 00000110 00000011 00000010 00000001 00000001 00000000 00000000 00000000 UBR HEX 019 00C 006 003 002 001 001 000 000 000 UBR HEX 0EF 077 03B 027 01D 013 00E 009 007 004 001 000 000 UBR HEX 299 14C 0A6 06E 052 036 029 01B 014 00D 006 003 001 UBR 25 12 6 3 2 1 1 0 0 0 Actual Freq 2404 4808 8929 15625 20833 31250 31250 62500 62500 62500 Desired % Clock Freq. Error MHz 2400 0.2 1.8432 4800 0.2 9600 7.5 14400 7.8 19200 7.8 28880 7.6 38400 22.9 57600 7.8 76800 22.9 115200 84.3 UBRRHI 7:4 or 3:0 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 UBRRHI 7:4 or 3:0 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 UBRRn 00101111 00010111 00001011 00000111 00000101 00000011 00000010 00000001 00000001 00000000 UBR HEX 02F 017 00B 007 005 003 002 001 001 000 UBR HEX 1DF 0EF 077 04F 03B 027 01D 013 00E 009 004 001 000 UBR HEX 411 208 103 0AC 081 056 040 02A 020 015 00A 004 002 UBR 47 23 11 7 5 3 2 1 1 0 Actual Freq 2400 4800 9600 14400 19200 28800 38400 57600 57600 115200 Desired % Freq. Error 2400 0.0 4800 0.0 9600 0.0 14400 0.0 19200 0.0 28880 0.3 38400 0.0 57600 0.0 76800 33.3 115200 0.0
Clock UBRRHI MHz 7:4 or 3:0 9.216 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 Clock UBRRHI MHz 7:4 or 3:0 25.576 0010 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
UBRRn 11101111 01110111 00111011 00100111 00011101 00010011 00001110 00001001 00000111 00000100 00000001 00000000 00000000
Actual Desired % Clock UBR Freq Freq. Error MHz 239 2400 2400 0.0 18.432 119 4800 4800 0.0 59 9600 9600 0.0 39 14400 14400 0.0 29 19200 19200 0.0 19 28800 28880 0.3 14 38400 38400 0.0 9 57600 57600 0.0 7 72000 76800 6.7 4 115200 115200 0.0 1 288000 230400 20.0 0 576000 460800 20.0 0 576000 912600 58.4
UBRRn 11011111 11101111 01110111 01001111 00111011 00100111 00011101 00010011 00001110 00001001 00000100 00000001 00000000
Actual Desired % UBR Freq Freq. Error 479 2400 2400 0.0 239 4800 4800 0.0 119 9600 9600 0.0 79 14400 14400 0.0 59 19200 19200 0.0 39 28800 28880 0.3 29 38400 38400 0.0 19 57600 57600 0.0 14 76800 76800 0.0 9 115200 115200 0.0 4 230400 230400 0.0 1 576000 460800 20.0 0 1152000 912600 20.8 Actual Desired % UBR Freq Freq. Error 1041 2399 2400 0.0 520 4798 4800 0.0 259 9615 9600 0.2 172 14451 14400 0.4 129 19231 19200 0.2 86 28736 28880 0.5 64 38462 38400 0.2 42 58140 57600 0.9 32 75758 76800 1.4 21 113636 115200 1.4 10 227273 230400 1.4 4 500000 460800 7.8 2 833333 912600 9.5
UBRRn 10011001 01001100 10100110 01101110 01010010 00110110 00101001 00011011 00010100 00001101 00000110 00000011 00000001
Actual Desired % Clock UBRRHI UBR Freq Freq. Error MHz 7:4 or 3:0 665 2400 2400 0.0 40 0100 332 4800 4800 0.0 0010 166 9572 9600 0.3 0001 110 14401 14400 0.0 0000 82 19259 19200 0.3 0000 54 29064 28880 0.6 0000 41 38060 38400 0.9 0000 27 57089 57600 0.9 0000 20 76119 76800 0.9 0000 13 114179 115200 0.9 0000 6 228357 230400 0.9 0000 3 399625 460800 15.3 0000 1 799250 912600 14.2 0000
UBRRn 00010001 00001000 00000011 10101100 10000001 01010110 01000000 00101010 00100000 00010101 00001010 00000100 00000010
UART0 and UART1 High Byte Baud-rate Register UBRRHI
Bit $20 ($40) Read/Write Initial Value 7 MSB1 R/W 0 R/W 0 R/W 0 6 5 4 LSB1 R/W 0 3 MSB0 R/W 0 R/W 0 R/W 0 2 1 0 LSB0 R/W 0 UBRRHI
The UART baud register is a 12-bit register. The 4 most significant bits are located in a separate register, UBRRHI. Note that both UART0 and UART1 share this register. Bit 7 to bit 4 of UBRRHI contain the 4 most significant bits of the UART1 baud register. Bit 3 to bit 0 contain the 4 most significant bits of the UART0 baud register.
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UART0 Baud-rate Register Low Byte - UBRR0
Bit $09 ($29) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 UBRR0
UART1 Baud-rate Register Low Byte - UBRR1
Bit $00 ($20) Read/Write Initial Value 7 MSB R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 R/W 0 6 5 4 3 2 1 0 LSB R/W 0 UBRR1
UBRRn stores the 8 least significant bits of the UART baud-rate register. Double Speed Transmission The FPSLIC provides a separate UART mode that allows the user to double the communication speed. By setting the U2X bit in UART Control and Status Register UCSRnA, the UART speed will be doubled. The data reception will differ slightly from normal mode. Since the speed is doubled, the receiver front-end logic samples the signals on the RXDn pin at a frequency 8 times the baud-rate. While the line is idle, one single sample of logic 0 will be interpreted as the falling edge of a start bit, and the start bit detection sequence is initiated. Let sample 1 denote the first zero-sample. Following the 1-to-0 transition, the receiver samples the RXDn pin at samples 4, 5 and 6. If two or more of these three samples are found to be logic 1s, the start bit is rejected as a noise spike and the receiver starts looking for the next 1to-0 transition. If however, a valid start bit is detected, sampling of the data bits following the start bit is performed. These bits are also sampled at samples 4, 5 and 6. The logical value found in at least two of the three samples is taken as the bit value. All bits are shifted into the transmitter shift register as they are sampled. Sampling of an incoming character is shown in Figure 67. Figure 67. Sampling Received Data when the Transmission Speed is Doubled
RXD START BIT RECEIVER SAMPLING D0 D1 D2 D3 D4 D5 D6 D7 STOP BIT
The Baud-rate Generator in Double UART Speed Mode
Note that the baud-rate equation is different from the equation(1) at page 126 when the UART speed is doubled:
f CK BAUD = ----------------------------8(UBR + 1 )
* * * BAUD = Baud-rate fCK= Crystal Clock Frequency UBR = Contents of the UBRRHI and UBRRn Registers, (0 - 4095)
1. This equation is only valid when the UART transmission speed is doubled.
Note:
For standard crystal frequencies, the most commonly used baud-rates can be generated by using the UBR settings in Table 35. UBR values which yield an actual baud-rate differing less than 1.5% from the target baud-rate, are bold in the table. However since the number of samples are reduced and the system clock might have some variance (this applies especially when using resonators), it is recommended that the baud-rate error is less than 0.5%. See Table 36 for the UBR settings at various crystal frequencies in double UART speed mode. 128
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Table 36. UBR Settings at Various Crystal Frequencies in Double UART Speed Mode
Clock UBRRHI MHz 7:4 or 3:0 1 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 UBR HEX UBR 033 51 019 25 00C 12 008 8 006 6 003 3 002 2 001 1 001 1 000 0 Actual Freq 2404 4808 9615 13889 17857 31250 41667 62500 62500 125000 Desired % Clock UBRRHI Freq. Error MHz 7:4 or 3:0 2400 0.2 1.843 0000 4800 0.2 0000 9600 0.2 0000 14400 3.7 0000 19200 7.5 0000 28880 7.6 0000 38400 7.8 0000 57600 7.8 0000 76800 22.9 0000 115200 7.8 0000 UBR UBRRn HEX 01011111 05F 00101111 02F 00010111 017 00001111 00F 00001011 00B 00000111 007 00000101 005 00000011 003 00000010 002 00000001 001 Actual Freq 2400 4800 9600 14400 19200 28800 38400 57600 76800 115200 Desired % Freq. Error 2400 0.0 4800 0.0 9600 0.0 14400 0.0 19200 0.0 28880 0.3 38400 0.0 57600 0.0 76800 0.0 115200 0.0
UBRRn 00110011 00011001 00001100 00001000 00000110 00000011 00000010 00000001 00000001 00000000
UBR 95 47 23 15 11 7 5 3 2 1
Clock UBRRHI MHz 7:4 or 3:0 9.216 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
UBRRn 11011111 11101111 01110111 01001111 00111011 00100111 00011101 00010011 00001110 00001001 00000100 00000010 00000000
UBR Actual HEX UBR Freq 1DF 479 2400 0EF 239 4800 077 119 9600 04F 79 14400 03B 59 19200 027 39 28800 01D 29 38400 013 19 57600 00E 14 76800 009 9 115200 004 4 230400 002 2 384000 000 0 1152000
Desired % Clock UBRRHI Freq. Error MHz 7:4 or 3:0 2400 0.0 18.43 0011 4800 0.0 0001 9600 0.0 0000 14400 0.0 0000 19200 0.0 0000 28880 0.3 0000 38400 0.0 0000 57600 0.0 0000 76800 0.0 0000 115200 0.0 0000 230400 0.0 0000 460800 20.0 0000 912600 20.8 0000
UBR UBRRn HEX 10111111 3BF 11011111 1DF 11101111 0EF 10011111 09F 01110111 077 01001111 04F 00111011 03B 00100111 027 00011101 01D 00010011 013 00001001 009 00000100 004 00000010 002
UBR 959 479 239 159 119 79 59 39 29 19 9 4 2
Actual Freq 2400 4800 9600 14400 19200 28800 38400 57600 76800 115200 230400 460800 768000
Desired % Freq. Error 2400 0.0 4800 0.0 9600 0.0 14400 0.0 19200 0.0 28880 0.3 38400 0.0 57600 0.0 76800 0.0 115200 0.0 230400 0.0 460800 0.0 912600 18.8
Clock UBRRHI MHz 7:4 or 3:0 25.576 0101 0010 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
UBRRn 00110011 10011001 01001110 11011101 10100110 01101110 01010010 00110111 00101001 00011011 00001101 00000110 00000011
UBR HEX UBR 533 1331 299 665 14E 334 0DD 221 0A6 166 06E 110 052 82 037 55 029 41 01B 27 00D 13 006 6 003 3
Actual Freq 2400 4800 9543 14401 19144 28802 38518 57089 76119 114179 228357 456714 799250
Desired % Clock UBRRHI Freq. Error MHz 7:4 or 3:0 40 2400 0.0 1000 4800 0.0 0100 9600 0.6 0010 14400 0.0 0001 19200 0.3 0001 28880 0.3 0000 38400 0.3 0000 57600 0.9 0000 76800 0.9 0000 115200 0.9 0000 230400 0.9 0000 460800 0.9 0000 912600 14.2 0000
UBRRn 00100010 00010001 00001000 01011010 00000011 10101100 10000001 01010110 01000000 00101010 00010101 00001010 00000100
UBR Actual HEX UBR Freq 822 2082 2400 411 1041 4798 208 520 9597 15A 346 14409 103 259 19231 0AC 172 28902 081 129 38462 056 86 57471 040 64 76923 02A 42 116279 015 21 227273 00A 10 454545 004 4 1000000
Desired % Freq. Error 2400 0.0 4800 0.0 9600 0.0 14400 0.1 19200 0.2 28880 0.1 38400 0.2 57600 0.2 76800 0.2 115200 0.9 230400 1.4 460800 1.4 912600 8.7
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2-wire Serial Interface (Byte Oriented)
The 2-wire Serial Bus is a bi-directional two-wire serial communication standard. It is designed primarily for simple but efficient integrated circuit (IC) control. The system is comprised of two lines, SCL (Serial Clock) and SDA (Serial Data) that carry information between the ICs connected to them. Various communication configurations can be designed using this bus. Figure 68 shows a typical 2-wire Serial Bus configuration. Any device connected to the bus can be Master or Slave. Figure 68. 2-wire Serial Bus Configuration
VCC
Device 1
Device 2
Device 3
.......
Device n
R1
R2
SCL SDA
The 2-wire Serial Interface provides a serial interface that meets the 2-wire Serial Bus specification and supports Master/Slave and Transmitter/Receiver operation at up to 400 kHz bus clock rate. The 2-wire Serial Interface has hardware support for the 7-bit addressing, but is easily extended to 10-bit addressing format in software. When operating in 2-wire Serial mode, i.e., when TWEN is set, a glitch filter is enabled for the input signals from the pins SCL and SDA, and the output from these pins are slew-rate controlled. The 2-wire Serial Interface is byte oriented. The operation of the serial 2-wire Serial Bus is shown as a pulse diagram in Figure 69, including the START and STOP conditions and generation of ACK signal by the bus receiver. Figure 69. 2-wire Serial Bus Timing Diagram
ACKNOWLEDGE FROM RECEIVER SDA MSB R/W BIT STOP CONDITION
SCL START CONDITION
1
2
7
8
9 ACK
1
2
8
9 ACK REPEATED START CONDITION
The block diagram of the 2-wire Serial Bus interface is shown in Figure 70.
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Figure 70. Block diagram of the 2-wire Serial Bus Interface
ADDRESS REGISTER AND COMPARATOR TWAR
INPUT SDA OUTPUT
DATA SHIFT REGISTER TWDR
ACK
INPUT SCL OUTPUT
START/STOP AND SYNC ARBITRATION
TIMING AND CONTROL
SERIAL CLOCK GENERATOR
CONTROL REGISTER TWCR
STATUS
STATE MACHINE AND STATUS DECODER
STATUS REGISTER TWSR
The CPU interfaces with the 2-wire Serial Interface via the following five I/O registers: the 2wire Serial Bit-rate Register (TWBR), the 2-wire Serial Control Register (TWCR), the 2-wire Serial Status Register (TWSR), the 2-wire Serial Data Register (TWDR), and the 2-wire Serial Address Register (TWAR, used in Slave mode).
The 2-wire Serial Bit-rate Register - TWBR
Bit $1C ($3C) Read/Write Initial Value 7 TWBR7 R/W 0 6 TWBR6 R/W 0 5 TWBR5 R/W 0 4 TWBR4 R/W 0 3 TWBR3 R/W 0 2 TWBR2 R/W 0 1 TWBR1 R/W 0 0 TWBR0 R/W 0 TWBR
AVR 8-BIT DATA BUS
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* Bits 7..0 - 2-wire Serial Bit-rate Register TWBR selects the division factor for the bit-rate generator. The bit-rate generator is a frequency divider which generates the SCL clock frequency in the Master modes according to the following equation:
f CK Bit-rate = ------------------------------------16 + 2(TWBR)
* * * Bit-rate = SCL frequency fCK = CPU Clock frequency TWBR = Contents of the 2-wire Serial Bit Rate Register
Both the receiver and the transmitter can stretch the Low period of the SCL line when waiting for user response, thereby reducing the average bit rate.
The 2-wire Serial Control Register - TWCR
Bit $36 ($56) Read/Write Initial Value 7 TWINT R/W 0 6 TWEA R/W 0 5 TWSTA R/W 0 4 TWSTO R/W 0 3 TWWC R 0 2 TWEN R/W 0 1 R 0 0 TWIE R/W 0 TWCR
* Bit 7 - TWINT: 2-wire Serial Interrupt Flag This bit is set by the hardware when the 2-wire Serial Interface has finished its current job and expects application software response. If the I-bit in the SREG and TWIE in the TWCR register are set (one), the MCU will jump to the interrupt vector at address $0046. While the TWINT flag is set, the bus SCL clock line Low period is stretched. The TWINT flag must be cleared by software by writing a logic 1 to it. Note that this flag is not automatically cleared by the hardware when executing the interrupt routine. Also note that clearing this flag starts the operation of the 2-wire Serial Interface, so all accesses to the 2-wire Serial Address Register - TWAR, 2-wire Serial Status Register - TWSR, and 2-wire Serial Data Register - TWDR must be complete before clearing this flag. * Bit 6 - TWEA: 2-wire Serial Enable Acknowledge Flag TWEA flag controls the generation of the acknowledge pulse. If the TWEA bit is set, the ACK pulse is generated on the 2-wire Serial Bus if the following conditions are met: * * * The device's own Slave address has been detected A general call has been received, while the TWGCE bit in the TWAR is set A data byte has been received in Master Receiver or Slave Receiver mode
By setting the TWEA bit Low the device can be virtually disconnected from the 2-wire Serial Bus temporarily. Address recognition can then be resumed by setting the TWEA bit again. * Bit 5 - TWSTA: 2-wire Serial Bus START Condition Flag The TWSTA flag is set by the CPU when it desires to become a Master on the 2-wire Serial Bus. The 2-wire serial hardware checks if the bus is available, and generates a Start condition on the bus if the bus is free. However, if the bus is not free, the 2-wire Serial Interface waits until a STOP condition is detected, and then generates a new Start condition to claim the bus Master status.
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* Bit 4 - TWSTO: 2-wire Serial Bus STOP Condition Flag TWSTO is a stop condition flag. In Master mode, setting the TWSTO bit in the control register will generate a STOP condition on the 2-wire Serial Bus. When the STOP condition is executed on the bus, the TWSTO bit is cleared automatically. In Slave mode, setting the TWSTO bit can be used to recover from an error condition. No stop condition is generated on the bus then, but the 2-wire Serial Interface returns to a well-defined unaddressed Slave mode. * Bit 3 - TWWC: 2-wire Serial Write Collision Flag Set when attempting to write to the 2-wire Serial Data Register - TWDR when TWINT is Low. This flag is updated at each attempt to write the TWDR register. * Bit 2 - TWEN: 2-wire Serial Interface Enable Flag The TWEN bit enables 2-wire serial operation. If this flag is cleared (zero), the bus outputs SDA and SCL are set to high impedance state and the input signals are ignored. The interface is activated by setting this flag (one). * Bit 1 - Res: Reserved Bit This bit is reserved in the AT94K and will always read as zero. * Bit 0 - TWIE: 2-wire Serial Interrupt Enable When this bit is enabled and the I-bit in SREG is set, the 2-wire Serial Interrupt will be activated for as long as the TWINT flag is High. The TWCR is used to control the operation of the 2-wire Serial Interface. It is used to enable the 2-wire Serial Interface, to initiate a Master access, to generate a receiver acknowledge, to generate a stop condition, and control halting of the bus while the data to be written to the bus are written to the TWDR. It also indicates a write collision if data is attempted written to TWDR while the register is inaccessible.
The 2-wire Serial Status Register - TWSR
Bit $1D ($3D) Read/Write Initial Value 7 TWS7 R 1 6 TWS6 R 1 5 TWS5 R 1 4 TWS4 R 1 3 TWS3 R 1 2 R 0 1 R 0 0 R 0 TWSR
* Bits 7..3 - TWS: 2-wire Serial Status These 5 bits reflect the status of the 2-wire Serial Logic and the 2-wire Serial Bus. * Bits 2..0 - Res: Reserved Bits These bits are reserved in the AT94K and will always read as zero TWSR is read only. It contains a status code which reflects the status of the 2-wire Serial Logic and the 2-wire Serial Bus. There are 26 possible status codes. When TWSR contains $F8, no relevant state information is available and no 2-wire Serial Interrupt is requested. A valid status code is available in TWSR one CPU clock cycle after the 2-wire Serial Interrupt flag (TWINT) is set by the hardware and is valid until one CPU clock cycle after TWINT is cleared by software. Table 40 to Table 44 give the status information for the various modes.
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The 2-wire Serial Data Register - TWDR
Bit $1F ($3F) Read/Write Initial Value 7 MSB R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 6 5 4 3 2 1 0 LSB R/W 1 TWDR
* Bits 7..0 - TWD: 2-wire Serial Data Register These eight bits constitute the next data byte to be transmitted, or the latest data byte received on the 2-wire Serial Bus. In transmit mode, TWDR contains the next byte to be transmitted. In receive mode, the TWDR contains the last byte received. It is writable while the 2-wire Serial Interface is not in the process of shifting a byte. This occurs when the 2-wire Serial Interrupt flag (TWINT) is set by the hardware. Note that the data register cannot be initialized by the user before the first interrupt occurs. The data in TWDR remains stable as long as TWINT is set. While data is shifted out, data on the bus is simultaneously shifted in. TWDR always contains the last byte present on the bus, except after a wake up from Power-down Mode, or Power-save Mode by the 2-wire Serial Interrupt. For example, in the case of the lost bus arbitration, no data is lost in the transition from Master-to-Slave. Receiving the ACK flag is controlled by the 2-wire Serial Logic automatically, the CPU cannot access the ACK bit directly.
The 2-wire Serial (Slave) Address Register - TWAR
Bit $1E ($3E) Read/Write Initial Value 7 MSB R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 R/W 1 6 5 4 3 2 1 LSB R/W 1 0 TWGCE R/W 0 TWAR
* Bits 7..1 - TWA: 2-wire Serial Slave Address Register These seven bits constitute the Slave address of the 2-wire Serial Bus interface unit. * Bit 0 - TWGCE: 2-wire Serial General Call Recognition Enable Bit This bit enables, if set, the recognition of the General Call given over the 2-wire Serial Bus. The TWAR should be loaded with the 7-bit Slave address (in the seven most significant bits of TWAR) to which the 2-wire Serial Interface will respond when programmed as a Slave transmitter or receiver, and not needed in the Master modes. The LSB of TWAR is used to enable recognition of the general call address ($00). There is an associated address comparator that looks for the Slave address (or general call address if enabled) in the received serial address. If a match is found, an interrupt request is generated.
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2-wire Serial Modes The 2-wire Serial Interface can operate in four different modes: * * * * Master Transmitter Master Receiver Slave Receiver Slave Transmitter
Data transfer in each mode of operation is shown in Figure 71 to Figure 74. These figures contain the following abbreviations: S: START condition R: Read bit (High level at SDA) W: Write bit (Low level at SDA) A: Acknowledge bit (Low level at SDA) A: Not acknowledge bit (High level at SDA) Data: 8-bit data byte P: STOP condition In Figure 71 to Figure 74, circles are used to indicate that the 2-wire Serial Interrupt flag is set. The numbers in the circles show the status code held in TWSR. At these points, an interrupt routine must be executed to continue or complete the 2-wire Serial Transfer. The 2-wire Serial Transfer is suspended until the 2-wire Serial Interrupt flag is cleared by software. The 2-wire Serial Interrupt flag is not automatically cleared by the hardware when executing the interrupt routine. Also note that the 2-wire Serial Interface starts execution as soon as this bit is cleared, so that all access to TWAR, TWDR and TWSR must have been completed before clearing this flag. When the 2-wire Serial Interrupt flag is set, the status code in TWSR is used to determine the appropriate software action. For each status code, the required software action and details of the following serial transfer are given in Table 40 to Table 44.
Master Transmitter Mode
In the Master Transmitter mode, a number of data bytes are transmitter to a Slave Receiver, see Figure 71. Before the Master Transmitter mode can be entered, the TWCR must be initialized as shown in Table 37. Table 37. TWCR: Master Transmitter Mode Initialization
TWCR value TWINT 0 TWEA X TWSTA 0 TWSTO 0 TWWC 0 TWEN 1 0 TWIE X
TWEN must be set to enable the 2-wire Serial Interface, TWSTA and TWSTO must be cleared. The Master Transmitter mode may now be entered by setting the TWSTA bit. The 2-wire Serial Logic will now test the 2-wire Serial Bus and generate a START condition as soon as the bus becomes free. When a START condition is transmitted, the 2-wire Serial Interrupt flag (TWINT) is set by the hardware, and the status code in TWSR will be $08. TWDR must then be loaded with the Slave address and the data direction bit (SLA+W). The TWINT flag must then be cleared by software before the 2-wire Serial Transfer can continue. The TWINT flag is cleared by writing a logic 1 to the flag. When the Slave address and the direction bit have been transmitted and an acknowledgment bit has been received, TWINT is set again and a number of status codes in TWSR are possible. Status codes $18, $20, or $38 apply to Master mode, and status codes $68, $78, or $B0 apply to Slave mode. The appropriate action to be taken for each of these status codes is 135
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detailed in Table 40. The data must be loaded when TWINT is High only. If not, the access will be discarded, and the Write Collision bit, TWWC, will be set in the TWCR register. This scheme is repeated until a STOP condition is transmitted by writing a logic 1 to the TWSTO bit in the TWCR register. After a repeated START condition (state $10) the 2-wire Serial Interface may switch to the Master Receiver mode by loading TWDR with SLA+R.
Master Receiver Mode
In the Master Receiver mode, a number of data bytes are received from a Slave Transmitter, see Figure 72. The transfer is initialized as in the Master Transmitter mode. When the START condition has been transmitted, the TWINT flag is set by the hardware. The software must then load TWDR with the 7-bit Slave address and the data direction bit (SLA+R). The 2-wire Serial Interrupt flag must then be cleared by software before the 2-wire Serial Transfer can continue. When the Slave address and the direction bit have been transmitted and an acknowledgment bit has been received, TWINT is set again and a number of status codes in TWSR are possible. Status codes $40, $48, or $38 apply to Master mode, and status codes $68, $78, or $B0 apply to Slave mode. The appropriate action to be taken for each of these status codes is detailed in Table 41. Received data can be read from the TWDR register when the TWINT flag is set High by the hardware. This scheme is repeated until a STOP condition is transmitted by writing a logic 1 to the TWSTO bit in the TWCR register. After a repeated START condition (state $10), the 2-wire Serial Interface may switch to the Master Transmitter mode by loading TWDR with SLA+W.
Slave Receiver Mode
In the Slave Receiver mode, a number of data bytes are received from a Master Transmitter, see Figure 73. To initiate the Slave Receiver mode, TWAR and TWCR must be initialized as follows: Table 38. TWAR: Slave Receiver Mode Initialization
TWAR value TWA6 TWA5 TWA4 TWA3 TWA2 TWA1 TWA0 TWGCE Device's own Slave address
The upper 7 bits are the address to which the 2-wire Serial Interface will respond when addressed by a Master. If the LSB is set, the 2-wire Serial Interface will respond to the general call address ($00), otherwise it will ignore the general call address. Table 39. TWCR: Slave Receiver Mode Initialization
TWCR value TWINT 0 TWEA 1 TWSTA 0 TWSTO 0 TWWC 0 TWEN 1 0 TWIE X
TWEN must be set to enable the 2-wire Serial Interface. The TWEA bit must be set to enable the acknowledgment of the device's own Slave address or the general call address. TWSTA and TWSTO must be cleared. When TWAR and TWCR have been initialized, the 2-wire Serial Interface waits until it is addressed by its own Slave address (or the general call address if enabled) followed by the data direction bit which must be "0" (write) for the 2-wire Serial Interface to operate in the Slave Receiver mode. After its own Slave address and the write bit have been received, the 2wire Serial Interrupt flag is set and a valid status code can be read from TWSR. The status code is used to determine the appropriate software action. The appropriate action to be taken for each status code is detailed in Table 42. The Slave Receiver mode may also be entered if arbitration is lost while the 2-wire Serial Interface is in the Master mode (see states $68 and $78).
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If the TWEA bit is reset during a transfer, the 2-wire Serial Interface will return a "Not Acknowledged" (1) to SDA after the next received data byte. While TWEA is reset, the 2-wire Serial Interface does not respond to its own Slave address. However, the 2-wire Serial Bus is still monitored and address recognition may resume at any time by setting TWEA. This implies that the TWEA bit may be used to temporarily isolate the 2-wire Serial Interface from the 2wire serial bus. In ADC Noise Reduction Mode, Power-down Mode and Power-save Mode, the clock system to the 2-wire Serial Interface is turned off. If the Slave Receiver mode is enabled, the interface can still acknowledge a general call and its own Slave address by using the 2-wire serial bus clock as a clock source. The part will then wake up from sleep and the 2-wire Serial Interface will hold the SCL clock Low during the wake up and until the TWCINT flag is cleared. Note that the 2-wire Serial Data Register - TWDR does not reflect the last byte present on the bus when waking up from these Sleep Modes.
Slave Transmitter Mode
In the Slave Transmitter mode, a number of data bytes are transmitted to a Master Receiver (see Figure 74). The transfer is initialized as in the Slave Receiver mode. When TWAR and TWCR have been initialized, the 2-wire Serial Interface waits until it is addressed by its own Slave address (or the general call address if enabled) followed by the data direction bit which must be "1" (read) for the 2-wire Serial Interface to operate in the Slave Transmitter mode. After its own Slave address and the read bit have been received, the 2-wire Serial Interrupt flag is set and a valid status code can be read from TWSR. The status code is used to determine the appropriate software action. The appropriate action to be taken for each status code is detailed in Table 43. The Slave Transmitter mode may also be entered if arbitration is lost while the 2-wire Serial Interface is in the Master mode (see state $B0). If the TWEA bit is reset during a transfer, the 2-wire Serial Interface will transmit the last byte of the transfer and enter state $C0 or state $C8. the 2-wire Serial Interface is switched to the not addressed Slave mode, and will ignore the Master if it continues the transfer. Thus the Master Receiver receives all "1" as serial data. While TWEA is reset, the 2-wire Serial Interface does not respond to its own Slave address. However, the 2-wire serial bus is still monitored and address recognition may resume at any time by setting TWEA. This implies that the TWEA bit may be used to temporarily isolate the 2-wire Serial Interface from the 2wire serial bus.
Miscellaneous States
There are two status codes that do not correspond to a defined 2-wire Serial Interface state: Status $F8 and Status $00, see Table 44. Status $F8 indicates that no relevant information is available because the 2-wire Serial Interrupt flag (TWINT) is not set yet. This occurs between other states, and when the 2-wire Serial Interface is not involved in a serial transfer. Status $00 indicates that a bus error has occurred during a 2-wire serial transfer. A bus error occurs when a START or STOP condition occurs at an illegal position in the format frame. Examples of such illegal positions are during the serial transfer of an address byte, a data byte or an acknowledge bit. When a bus error occurs, TWINT is set. To recover from a bus error, the TWSTO flag must set and TWINT must be cleared by writing a logic 1 to it. This causes the 2-wire Serial Interface to enter the not addressed Slave mode and to clear the TWSTO flag (no other bits in TWCR are affected). The SDA and SCL lines are released and no STOP condition is transmitted.
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Table 40. Status Codes for Master Transmitter Mode
Application Software Response Status Code (TWSR) $08 Status of the 2-wire Serial Bus and 2-wire Serial Hardware A START condition has been transmitted A repeated START condition has been transmitted To TWCR To/From TWDR Load SLA+W STA X STO 0 TWINT 1 TWEA X Next Action Taken by 2-wire Serial Hardware SLA+W will be transmitted; ACK or NOT ACK will be received Load SLA+W or Load SLA+R X X 0 0 1 1 X X SLA+W will be transmitted; ACK or NOT ACK will be received SLA+R will be transmitted; Logic will switch to Master Receiver mode $18 SLA+W has been transmitted; ACK has been received Load data byte or No TWDR action or No TWDR action or No TWDR action 0 1 0 1 0 0 1 1 1 1 1 1 X X X X Data byte will be transmitted and ACK or NOT ACK will be received Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset Data byte will be transmitted and ACK or NOT ACK will be received Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset Data byte will be transmitted and ACK or NOT ACK will be received Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset Data byte will be transmitted and ACK or NOT ACK will be received Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset 2-wire serial bus will be released and not addressed Slave mode entered A START condition will be transmitted when the bus becomes free
$10
$20
SLA+W has been transmitted; NOT ACK has been received
Load data byte or No TWDR action or No TWDR action or No TWDR action
0 1 0 1
0 0 1 1
1 1 1 1
X X X X
$28
Data byte has been transmitted; ACK has been received
Load data byte or No TWDR action or No TWDR action or No TWDR action
0 1 0 1
0 0 1 1
1 1 1 1
X X X X
$30
Data byte has been transmitted; NOT ACK has been received
Load data byte or No TWDR action or No TWDR action or No TWDR action
0 1 0 1
0 0 1 1
1 1 1 1
X X X X
$38
Arbitration lost in SLA+W or data bytes
No TWDR action or No TWDR action
0 1
0 0
1 1
X X
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Figure 71. Formats and States in the Master Transmitter Mode
MT
Successfull transmission to a slave receiver
S
SLA
W
A
DATA
A
P
$08
Next transfer started with a repeated start condition
$18
$28
S
SLA
W
$10
Not acknowledge received after the slave address
A
P
R
$20
MR
Not acknowledge received after a data byte
A
P
$30
Arbitration lost in slave address or data byte
A or A
Other master continues
A or A
Other master continues
$38
Arbitration lost and addressed as slave
$38
Other master continues
A
$68
$78
$B0
To corresponding states in slave mode
From master to slave
DATA
A
Any number of data bytes and their associated acknowledge bits This number (contained in TWSR) corresponds to a defined state of the 2-wire serial bus
From slave to master
n
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Table 41. Status Codes for Master Receiver Mode
Application Software Response Status Code (TWSR) $08 Status of the 2-wire Serial Bus and 2-wire Serial Hardware A START condition has been transmitted A repeated START condition has been transmitted To TWCR To/From TWDR Load SLA+R STA X STO 0 TWINT 1 TWEA X Next Action Taken by 2-wire Serial Hardware SLA+R will be transmitted ACK or NOT ACK will be received Load SLA+R or Load SLA+W X X 0 0 1 1 X X SLA+R will be transmitted ACK or NOT ACK will be received SLA+W will be transmitted Logic will switch to Master Transmitter mode $38 Arbitration lost in SLA+R or NOT ACK bit No TWDR action or No TWDR action $40 SLA+R has been transmitted; ACK has been received No TWDR action or No TWDR action No TWDR action or No TWDR action or No TWDR action 0 1 0 0 1 0 1 0 0 0 0 0 1 1 1 1 1 1 1 1 1 X X 0 1 X X X 2-wire serial bus will be released and not addressed Slave mode will be entered A START condition will be transmitted when the bus becomes free Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Repeated START will be transmitted STOP condition will be transmitted and TWSTO flag will be reset STOP condition followed by a START condition will be transmitted and TWSTO flag will be reset
$10
$48
SLA+R has been transmitted; NOT ACK has been received
$50
Data byte has been received; ACK has been returned
Read data byte or Read data byte Read data byte or Read data byte or Read data byte
0 0 1 0 1
0 0 0 1 1
1 1 1 1 1
0 1 X X X
$58
Data byte has been received; NOT ACK has been returned
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Figure 72. Formats and States in the Master Receiver Mode
MR
Successfull reception from a slave receiver
S
SLA
R
A
DATA
A
DATA
A
P
$08
Next transfer started with a repeated start condition
$40
$50
$58
S
SLA
R
$10
Not acknowledge received after the slave address
A
P
W
$48
MT
Arbitration lost in slave address or data byte
A or A
Other master continues
A
Other master continues
$38
Arbitration lost and addressed as slave
$38
Other master continues
A
$68
$78
$B0
To corresponding states in slave mode
From master to slave
DATA
A
Any number of data bytes and their associated acknowledge bits This number (contained in TWSR) corresponds to a defined state of the 2-wire serial bus
From slave to master
n
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Table 42. Status Codes for Slave Receiver Mode
Application Software Response Status Code (TWSR) $60 Status of the 2-wire Serial Bus and 2-wire Serial Hardware Own SLA+W has been received; ACK has been returned To TWCR To/From TWDR No TWDR action or No TWDR action No TWDR action or No TWDR action STA X X X X STO 0 0 0 0 TWINT 1 1 1 1 TWEA 0 1 0 1 Next Action Taken by 2-wire Serial Hardware Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Switched to the not addressed Slave mode; no recognition of own SLA or GCA Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1" Switched to the not addressed Slave mode; no recognition of own SLA or GCA; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1"; a START condition will be transmitted when the bus becomes free
$68
Arbitration lost in SLA+R/W as Master; own SLA+W has been received; ACK has been returned General call address has been received; ACK has been returned
$70
No TWDR action or No TWDR action No TWDR action or No TWDR action
X X X X
0 0 0 0
1 1 1 1
0 1 0 1
$78
Arbitration lost in SLA+R/W as Master; General call address has been received; ACK has been returned Previously addressed with own SLA+W; data has been received; ACK has been returned Previously addressed with own SLA+W; data has been received; NOT ACK has been returned
$80
No TWDR action or No TWDR action Read data byte or Read data byte or
X X 0 0
0 0 0 0
1 1 1 1
0 1 0 1
$88
Read data byte or
1
0
1
0
Read data byte
1
0
1
1
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Table 42. Status Codes for Slave Receiver Mode (Continued)
Application Software Response Status Code (TWSR) $90 Status of the 2-wire Serial Bus and 2-wire Serial Hardware Previously addressed with general call; data has been received; ACK has been returned Previously addressed with general call; data has been received; NOT ACK has been returned To TWCR To/From TWDR Read data byte or Read data byte Read data byte or Read data byte or STA X X 0 0 STO 0 0 0 0 TWINT 1 1 1 1 TWEA 0 1 0 1 Next Action Taken by 2-wire Serial Hardware Data byte will be received and NOT ACK will be returned Data byte will be received and ACK will be returned Switched to the not addressed Slave mode; no recognition of own SLA or GCA Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1" Switched to the not addressed Slave mode; no recognition of own SLA or GCA; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1"; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; no recognition of own SLA or GCA Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1" Switched to the not addressed Slave mode; no recognition of own SLA or GCA; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1"; a START condition will be transmitted when the bus becomes free
$98
Read data byte or
1
0
1
0
Read data byte
1
0
1
1
$A0
A STOP condition or repeated START condition has been received while still addressed as Slave
Read data byte or Read data byte or
0 0
0 0
1 1
0 1
Read data byte or
1
0
1
0
Read data byte
1
0
1
1
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Rev. 1138F-FPSLI-06/02
Figure 73. Formats and States in the Slave Receiver Mode
Reception of the own slave address and one or more data bytes. All are acknowledged
S
SLA
W
A
DATA
A
DATA
A
P or S
$60
Last data byte received is not acknowledged
$80
$80
$A0
A
P or S
$88
Arbitration lost as master and addressed as slave
A
$68
Reception of the general call address and one or more data bytes
General Call
A
DATA
A
DATA
A
P or S
$70
Last data byte received is not acknowledged
$90
$90
$A0
A
P or S
$98
Arbitration lost as master and addressed as slave by general call
A
$78
From master to slave
DATA
A
Any number of data bytes and their associated acknowledge bits This number (contained in TWSR) corresponds to a defined state of the 2-wire serial bus
From slave to master
n
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Table 43. Status Codes for Slave Transmitter Mode
Application Software Response Status Code (TWSR) $A8 Status of the 2-wire Serial Bus and 2-wire Serial Hardware Own SLA+R has been received; ACK has been returned To TWCR To/From TWDR Load data byte or Load data byte Load data byte or Load data byte STA X X X X STO 0 0 0 0 TWINT 1 1 1 1 TWEA 0 1 0 1 Next Action Taken by 2-wire Serial Hardware Last data byte will be transmitted and NOT ACK should be received Data byte will be transmitted and ACK should be received Last data byte will be transmitted and NOT ACK should be received Data byte will be transmitted and ACK should be received Last data byte will be transmitted and NOT ACK should be received Data byte will be transmitted and ACK should be received Switched to the not addressed Slave mode; no recognition of own SLA or GCA Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1" Switched to the not addressed Slave mode; no recognition of own SLA or GCA; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1"; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; no recognition of own SLA or GCA Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1" Switched to the not addressed Slave mode; no recognition of own SLA or GCA; a START condition will be transmitted when the bus becomes free Switched to the not addressed Slave mode; own SLA will be recognized; GCA will be recognized if GC = "1"; a START condition will be transmitted when the bus becomes free
$B0
Arbitration lost in SLA+R/W as Master; own SLA+R has been received; ACK has been returned Data byte in TWDR has been transmitted; ACK has been received
$B8
Load data byte or Load data byte No TWDR action or No TWDR action or
X X 0 0
0 0 0 0
1 1 1 1
0 1 0 1
$C0
Data byte in TWDR has been transmitted; NOT ACK has been received
No TWDR action or
1
0
1
0
No TWDR action
1
0
1
1
$C8
Last data byte in TWDR has been transmitted (TWAE = "0"); ACK has been received
No TWDR action or No TWDR action or
0 0
0 0
1 1
0 1
No TWDR action or
1
0
1
0
No TWDR action
1
0
1
1
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Rev. 1138F-FPSLI-06/02
Figure 74. Formats and States in the Slave Transmitter Mode
Reception of the own slave address and one or more data bytes
S
SLA
R
A
DATA
A
DATA
A
P or S
$A8
Arbitration lost as master and addressed as slave
$B8
$C0
A
$B0
Last data byte transmitted.
A
All 1's
P or S
$C8
From master to slave
DATA
A
Any number of data bytes and their associated acknowledge bits This number (contained in TWSR) corresponds to a defined state of the 2-wire serial bus
From slave to master
n
Table 44. Status Codes for Miscellaneous States
Application Software Response Status Code (TWSR) $F8 Status of the 2-wire Serial Bus and 2-wire Serial Hardware No relevant state information available; TWINT = "0" Bus error due to an illegal START or STOP condition To TWCR To/From TWDR No TWDR action STA STO TWINT TWEA Next Action Taken by 2-wire Serial Hardware Wait or proceed current transfer
No TWCR action
$00
No TWDR action
0
1
1
X
Only the internal hardware is affected; no STOP condition is sent on the bus. In all cases, the bus is released and TWSTO is cleared.
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I/O Ports
All AVR ports have true read-modify-write functionality when used as general I/O ports. This means that the direction of one port pin can be changed without unintentionally changing the direction of any other pin with the SBI and CBI instructions. The same applies for changing drive value (if configured as output) or enabling/disabling of pull-up resistors (if configured as input). PortD is an 8-bit bi-directional I/O port with internal pull-up resistors. Three I/O memory address locations are allocated for the PortD, one each for the Data Register - PORTD, $12($32), Data Direction Register - DDRD, $11($31) and the Port D Input Pins - PIND, $10($30). The Port D Input Pins address is read only, while the Data Register and the Data Direction Register are read/write. The PortD output buffers can sink 20 mA. As inputs, PortD pins that are externally pulled Low will source current if the pull-up resistors are activated.
PortD
PortD Data Register - PORTD
Bit $12 Read/Write Initial Value 7 PORTD7 R/W 1 6 PORTD6 R/W 1 5 PORTD5 R/W 1 4 PORTD4 R/W 1 3 PORTD3 R/W 1 2 PORTD2 R/W 1 1 PORTD1 R/W 1 0 PORTD0 R/W 1 PORTD
PortD Data Direction Register - DDRD
Bit $11 Read/Write Initial Value 7 DDD7 R/W 0 6 DDD6 R/W 0 5 DDD5 R/W 0 4 DDD4 R/W 0 3 DDD3 R/W 0 2 DDD2 R/W 0 1 DDD1 R/W 0 0 DDD0 R/W 0 DDRD
PortD Input Pins Address - PIND
Bit $10 Read/Write Initial Value 7 PIND7 R Pull1 6 PIND6 R Pull1 5 PIND5 R Pull1 4 PIND4 R Pull1 3 PIND3 R Pull1 2 PIND2 R Pull1 1 PIND1 R Pull1 0 PIND0 R Pull1 PIND
The PortD Input Pins address - PIND - is not a register, and this address enables access to the physical value on each PortD pin. When reading PORTD, the PortD Data Latch is read, and when reading PIND, the logical values present on the pins are read.
PortD as General Digital I/O
PDn, General I/O pin: The DDDn bit in the DDRD register selects the direction of this pin. If DDDn is set (one), PDn is configured as an output pin. If DDDn is cleared (zero), PDn is configured as an input pin. If PDn is set (one) when configured as an input pin the MOS pull-up resistor is activated. To switch the pull-up resistor off the PDn has to be cleared (zero) or the pin has to be configured as an output pin. The port pins are input with pull-up when a reset condition becomes active, even if the clock is not running, see Table 45.
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Table 45. DDDn(1) Bits on PortD Pins
DDDn(1) 0 0 1 1 Note: PORTDn(1) 0 1 0 1 1. n: 7,6...0, pin number I/O Input Input Output Output Pull-up No Yes No No Comment Tri-state (High-Z) PDn will source current if external pulled low (default) Push-pull zero output Push-pull one output
Figure 75. PortD Schematic Diagram
MOS PULLUP DL RESET
RD RESET R Q DL GTS WD DDD* D
RL PD* Q PORTD* RESET R D
WL
RP
GTS: Global Tri-State DL: Configuration Download WL: Write PORTD WD: Write DDRD RL: Read PORTD Latch RD: Read DDRD RP: Read PORTD Pin
PortE
PortE is an 8-bit bi-directional I/O port with internal pull-up resistors. Three I/O memory address locations are allocated for the PortE, one each for the Data Register - PORTE, $07($27), Data Direction Register - DDRE, $06($26) and the PortE Input Pins - PINE, $05($25). The PortE Input Pins address is read only, while the Data Register and the Data Direction Register are read/write. The PortE output buffers can sink 20 mA. As inputs, PortE pins that are externally pulled Low will source current if the pull-up resistors are activated. All PortE pins have alternate functions as shown in Table 46.
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Table 46. PortE Pins Alternate Functions Controlled by SCR and AVR I/O Registers
Port Pin PE0 PE1 PE2 PE3 Alternate Function TX0 (UART0 transmit pin) RX0 (UART0 receive pin) TX1 (UART1 transmit pin) RX1 (UART1 receive pin) INT0 (external Interrupt0 input) INT1 (external Interrupt0 input) INT2 (external Interrupt0 input) INT3 (external Interrupt0 input) Input External Timer0 clock Output Output compare Timer0/PWM0 Output compare Timer2/PWM2 Output compare Timer1B/PWM1B Output compare Timer1A/PWM1A
PE4 PE5 PE6 PE7
External Timer1 clock Input capture Counter1
When the pins are used for the alternate function the DDRE and PORTE register has to be set according to the alternate function description.
PortE Data Register - PORTE
Bit $07 ($27) Read/Write Initial Value 7 PORTE7 R/W 1 6 PORTE6 R/W 1 5 PORTE5 R/W 1 4 PORTE4 R/W 1 3 PORTE3 R/W 1 2 PORTE2 R/W 1 1 PORTE1 R/W 1 0 PORTE0 R/W 1 PORTE
PortE Data Direction Register - DDRE
Bit $06 ($26) Read/Write Initial Value 7 DDE7 R/W 0 6 DDE6 R/W 0 5 DDE5 R/W 0 4 DDE4 R/W 0 3 DDE3 R/W 0 2 DDE2 R/W 0 1 DDE1 R/W 0 0 DDE0 R/W 0 DDRE
PortE Input Pins Address - PINE
Bit $05 ($25) Read/Write Initial Value 7 PINE7 R Pull1 6 PINE6 R Pull1 5 PINE5 R Pull1 4 PINE4 R Pull1 3 PINE3 R Pull1 2 PINE2 R Pull1 1 PINE1 R Pull1 0 PINE0 R Pull1 PINE
The PortE Input Pins address - PINE - is not a register, and this address enables access to the physical value on each PortE pin. When reading PORTE, the PortE Data Latch is read, and when reading PINE, the logical values present on the pins are read.
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LowPortE as General Digital I/O
PEn, General I/O pin: The DDEn bit in the DDRE register selects the direction of this pin. If DDEn is set (one), PEn is configured as an output pin. If DDEn is cleared (zero), PEn is configured as an input pin. If PEn is set (one) when configured as an input pin, the MOS pull-up resistor is activated. To switch the pull-up resistor off the PEn has to be cleared (zero) or the pin has to be configured as an output pin. The port pins are input with pull-up when a reset condition becomes active, even if the clock is not running. Table 47. DDEn(1) Bits on PortE Pins
DDEn(1) 0 0 1 1 Note: PORTEn(1) 0 1 0 1 I/O Input Input Output Output Pull-up No Yes No No Comment Tri-state (High-Z) PDn(1) will source current if external pulled Low (default). Push-pull zero output Push-pull one output
1. n: 7,6...0, pin number
Alternate Functions of PortE
* PortE, Bit 0 UART0 Transmit Pin. * PortE, Bit 1 UART0 Receive Pin. Receive Data (Data input pin for the UART0). When the UART0 receiver is enabled this pin is configured as an input regardless of the value of DDRE0. When the UART0 forces this pin to be an input, a logic 1 in PORTE0 will turn on the internal pull-up. * PortE, Bit 2 UART1 Transmit Pin. The alternate functions of Port E as UART0 pins are enabled by setting bit SCR52 in the FPSLIC System Control Register. This is necessary only in smaller pinout packages where the UART signals are not bonded out. The alternate functions of Port E as UART1 pins are enabled by setting bit SCR53 in the FPSLIC System Control Register. * PortE, Bit 3 UART1 Receive Pin. Receive Data (Data input pin for the UART1). When the UART1 receiver is enabled this pin is configured as an input regardless of the value of DDRE2. When the UART1 forces this pin to be an input, a logic 1 in PORTE2 will turn on the internal pull-up. * PortE, Bit 4-7 External Interrupt sources 0/1/2/3: The PE4 - PE7 pins can serve as external interrupt sources to the MCU. Interrupts can be triggered by low-level on these pins. The internal pullup MOS resistors can be activated as described above. The alternate functions of PortE as Interrupt pins by setting a bit in the System Control Register. INT0 is controlled by SCR48. INT1 is controlled by SCR49. INT2 is controlled by SCR50. INT3 is controlled by SCR51. PortE, Bit 7 also shares a pin with the configuration control signal CHECK. Lowering CON to initiate an FPSLIC download (whether for loading or Checking) causes the PE7/CHECK pin to immediately tri-state. This function happens only if the Check pin has been enabled in the system control register. The use of the Check pin will NOT disable the use of that pin as an input to PE7 nor as an input as alternate INT3.
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Alternate I/O Functions of PortE
PortE may also be used for various Timer/Counter functions, such as External Input Clocks (TC0 and TC1), Input Capture (TC1), Pulse Width Modulation (TC0, TC1 and TC2), and toggling upon an Output Compare (TC0, TC1 and TC2). For a detailed pinout description, consult Table 46 on page 149. For more information on the function of each pin, See "Timer/Counters" on page 85. Note that all port pins are synchronized. The synchronization latches are, however, not shown in the figures. Figure 76. PortE Schematic Diagram (Pin PE0)
MOS PULL-UP DL RESET
PortE Schematics
RD RESET R Q DL GTS WD DDE0 D
TX0ENABLE SCR(52)
RL 0 PE0 1 Q PORTE0 TX0D RESET R D
WL
RP T0 GTS: Global Tri-state DL: Configuration Download TX0ENABLE MOS PULL-UP DL RESET SCR(52) WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin TX0D: UART 0 Transmit Data TX0ENABLE: UART 0 Transmit Enable DL TX0 TX0D GTS SCR: System Control Register T0: Timer/Counter0 Clock
DATA BUS
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Rev. 1138F-FPSLI-06/02
Figure 77. PortE Schematic Diagram (Pin PE1)
MOS PULL-UP DL RESET
RD RESET R Q DDE1 D
DL GTS
WD
SCR(52) RL 0 PE1 1 OC0/PMW0 Q PORTE1 COM00 COM01 WL RESET R D
RP GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin RX0D: UART 0 Receive Data SCR: System Control Register OC0/PMW0: Timer/Counter 0 Output Compare COM0*: Timer/Counter0 Control Bits
SCR(52) MOS PULL-UP 0 RX0D 1
RX0
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AT94K Series FPSLIC
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DATA BUS
AT94K Series FPSLIC
Figure 78. PortE Schematic Diagram (Pin PE2)
MOS PULL-UP DL RESET
RD RESET R Q DL GTS WD DDE2 D
TX1ENABLE SCR(53)
RL 0 PE2 1 Q PORTE2 TX1D RESET R D
WL
RP TX1ENABLE MOS PULL-UP DL RESET SCR(53) GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE DL TX1 TX1D GTS RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin TX1D: UART 1 Transmit Data TX1ENABLE: UART 1 Transmit Enable SCR: System Control Register
DATA BUS
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Rev. 1138F-FPSLI-06/02
PortE Schematic Diagram (Pin PE3)
MOS PULL-UP DL RESET
RD RESET R Q DDE3 D
DL GTS
WD
SCR(53) RL 0 PE3 1 OC2/PMW2 Q PORTE3 COM20 COM21 WL RESET R D
RP
SCR(53) MOS PULL-UP 0 RX1D 1 GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin RX1 RX1D: UART 1 Receive Data SCR: System Control Register OC2/PMW2: Timer/Counter 2 Output Compare COM2*: Timer/Counter2 Control Bits
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AT94K Series FPSLIC
Figure 79. PortE Schematic Diagram (Pin PE4)
MOS PULL-UP DL RESET
RD RESET R Q DDE4 D
DL GTS
WD
SCR(48) RL PE4 Q PORTE4 RESET R D
WL
RP T1
SCR(48) MOS PULL-UP 0 extintp0 1 GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin INTP0 extintp0: External Interrupt 0 SCR: System Control Register T1: Timer/Counter1 External Clock
DATA BUS
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Figure 80. PortE Schematic Diagram (Pin PE5)
MOS PULL-UP DL RESET
RD RESET R Q DDE5 D
DL GTS
WD
SCR(49) RL 0 PE5 1 OC1B Q PORTE5 COM1B0 COM1B1 WL RESET R D
RP GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin extintp1: External Interrupt 1 SCR: System Control Register OC1B: Timer/Counter1 Output Compare B COM1B*: Timer/Counter1 B Control Bits
SCR(49) MOS PULL-UP 0 extintp1 1
INTP1
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AT94K Series FPSLIC
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DATA BUS
AT94K Series FPSLIC
Figure 81. PortE Schematic Diagram (Pin PE6)
MOS PULL-UP DL RESET
RD RESET R Q DDE6 D
DL GTS SCR(50)
WD
RL 0 PE6 1 OC1A Q PORTE6 COM1A0 COM1A1 WL RESET R D
RP GTS: Global Tri-State DL: Configuration Download SCR(50) MOS PULL-UP 0 extintp2 1 WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin extintp2: External Interrupt 2 SCR: System Control Register OC1A: Timer/Counter1 Output Compare A COM1A*: Timer/Counter1 A Control Bits INTP2
DATA BUS
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Rev. 1138F-FPSLI-06/02
Figure 82. PortE Schematic Diagram (Pin PE7)
MOS PULL-UP DL RESET
RD RESET R Q DDE7 D
DL GTS
WD
SCR(51) RL PE7 Q PORTE7 RESET R D
WL
RP ICP
SCR(51) MOS PULL-UP 0 extintp3 1 GTS: Global Tri-State DL: Configuration Download WL: Write PORTE WD: Write DDRE RL: Read PORTE Latch RD: Read DDRE RP: Read PORTE Pin INTP3 extintp3: External Interrupt 3 SCR: System Control Register ICP: Timer/Counter Input Capture Pin
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AT94K Series FPSLIC
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DATA BUS
AT94K Series FPSLIC
AC & DC Timing Characteristics
Absolute Maximum Ratings*(1)
Operating Temperature.................................. -55C to +125 C Storage Temperature ..................................... -65 C to +150C Voltage(2) on Any Pin with Respect to Ground .......................................-0.5V to 4.0V Supply Voltage (VCC ) .........................................-0.5V to +4.0V Maximum Soldering Temp. (10 sec. @ 1/16 in.)............. 250C ESD (RZAP = 1.5K, CZAP = 100 pF)................................. 2000V Notes: 1. For AL parts only 2. Minimum voltage of -0.5V DC which may undershoot to -2.0V for pulses of less than 20 ns. *NOTICE: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those listed under operating conditions is not implied. Exposure to Absolute Maximum Rating conditions for extended periods of time may affect device reliability.
DC and AC Operating Range - 3.3V Operation
AT94K Commercial Operating Temperature (Case) VCC Power Supply Input Voltage Level (CMOS) High (VIHC) Low (VILC) 0C - 70C 3.3V 0.3V 70% - 100% VCC 0 - 30% VCC AT94K Industrial -40C - 85C 3.3V 0.3V 70% - 100% VCC 0 - 30% V CC
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DC Characteristics - 3.3V Operation - Commercial/Industrial (Preliminary)
TA = -40C to 85C, VCC = 2.7V to 3.6V (unless otherwise noted(1))
Symbol VIH VIH1 VIH2 VIL VIL1 Parameter High-level Input Voltage Input High-voltage Input High-voltage Low-level Input Voltage Input Low-voltage Conditions CMOS XTAL RESET CMOS XTAL IOH = 4 mA V CC = V CC Minimum VOH High-level Output Voltage IOH = 12 mA V CC = 3.0V IOH = 16 mA V CC = 3.0V IOL = -4 mA V CC = 3.0V VOL Low-level Output Voltage IOL = -12 mA V CC = 3.0V IOL = -16 mA V CC = 3.0V RRST RI/O IIH Reset Pull-up I/O Pin Pull-up High-level Input Current V IN = VCC Maximum With Pull-down, V IN = VCC Low-level Input Current High-level Tri-state Output Leakage Current Low-level Tri-state Output Leakage Current Standby Current Consumption V IN = VSS With Pull-up, V IN = VSS Without Pull-down, VIN = V CC Maximum With Pull-down, V IN = VCC Maximum Without Pull-up, V IN = VSS With Pull-up, V IN = VSS Standby, Unprogrammed Active, V CC = 3V(1) 25 MHz Idle, VCC = 3V (1) Power-down, VCC = 3V (1) WDT Enable ICC Power Supply Current Power-down, VCC = 3V (1) WDT Disable Power-save, VCC = 3V(1) WDT Disable FPGA Core Current Consumption CIN Input Capacitance All Pins 75 -10 -300 - - - - - - - - -150 0.6 80(4) - 60 30 50 2 - -75 0.5 - 1.0 500 200 400 - 10 150 Minimum(3) 0.7 VCC 0.7 VCC(3) 0.85 VCC(3) -0.3 -0.5 2.1 2.1 2.1 - - - 100 35 - 75 -10 -300 Typical - - - - - - - - - - - - - - 150 - -150 Maximum(2) 5.5 VCC + 0.5 VCC + 0.5 30% V CC 0.1(2) - - - 0.4 0.4 0.4 500 120 10 300 - -75 10 300 Units V V V V V V V V V V V k k A A A A A A A A mA mA mA A A A mA/MHz pF
IIL
IOZH
IOZL
Notes:
1. 2. 3. 4.
Complete FPSLIC device with static FPGA core (no clock in FPGA active). "Maximum" is the highest value where the pin is guaranteed to be read as Low. "Minimum" is the lowest value where the pin is guaranteed to be read as High. 54 mA for AT94K05 devices.
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Power-On Power Supply Requirements
Atmel FPGAs require a minimum rated power supply current capacity to insure proper initialization, and the power supply ramp-up time does affect the current required. A fast ramp-up time requires more current than a slow ramp-up time.
Table 48. Power-On Power Supply Requirements(1)
Device AT94K05AL AT94K10AL AT94K20AL AT94K40AL Notes: Description Maximum Current Supply Maximum Current Supply Maximum Current(2)(3) 50 mA 100 mA
1. This specification applies to Commercial and Industrial grade products only. 2. Devices are guaranteed to initialize properly at 50% of the minimum current listed above. A larger capacity power supply may result in a larger initialization current. 3. Ramp-up time is measured from 0 V DC to 3.6 V DC. Peak current required lasts less than 2 ms, and occurs near the internal power on reset threshold voltage.
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FPSLIC Dual-port SRAM Characteristics
The Dual-port SRAM operates in single-edge clock controlled mode during read operations, and a double-edge controlled mode during write operations. Addresses are clocked internally on the rising edge of the clock signal (ME). Any change of address without a rising edge of ME is not considered. In read mode, the rising clock edge triggers data read without any significant constraint on the length of the clock pulse. The WE signal must be changed and held Low before the rising edge of ME to signify a read cycle. The WE signal should then remain Low until the falling edge of the clock. In write mode, data applied to the inputs is latched on either the falling edge of WE or the falling edge of the clock, whichever comes earlier, and written to memory. Also, WE must be High before the rising edge of ME to signify a write cycle. If data inputs change during a write cycle, only the value present at the write end is considered and written to the address clocked at the ME rise. A write cycle ending on WE fall does not turn into a read cycle - the next cycle will be a read cycle if WE remains Low during rising edge of ME. Figure 83. SRAM Read Cycle Timing Diagram
ADDR Address Valid tADS CLK (ME) t RDS tADH t MEL t MEH t RDH
WE
t ADS t ADH t RDS t RDH t ACC t MEH t MEL
- Address Setup - Address Hold - Read Cycle Setup - Read Cycle Hold - Access Time from posedge ME - Minimum ME High - Minimum ME Low
t ACC DATA READ Previous Data Output Valid
Figure 84. SRAM Write Cycle Timing Diagram
ADDR Address Valid tADS CLK (ME) t WRS WE t WDS t WDS DATA WRITE t WDH t WDH t ADH
t ADS - Address Setup t ADH - Address Hold t WRS - Write Cycle Setup t MPW - Minimum Write Duration t WDS - Data Setup to Write End t WDH - Data Hold to Write End
tMPW t MPW
Data Valid
Frame Interface
The FPGA Frame Clock phase is selectable (see "System Control Register - FPGA/AVR" on page 30). This document refers to the clock at the FPGA/Dual-port SRAM interface as ME (the relation of ME to data, address and write enable does not change). By default, FrameClock is inverted (ME = ~FrameClock). Selecting the non-inverted phase assigns ME = FrameClock. Recall, the Dual-port SRAM operates in single-edge clock controlled mode during read operations, and double-edge clock controlled mode during writes. Addresses are clocked internally on the rising edge of the clock signal (ME). Any change of address without a rising edge of ME is not considered.
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AT94K Series FPSLIC
Table 49. SRAM Read Cycle Timing Numbers Commercial 3.3V 10%/Industrial 3.3V 10%
Commercial Symbol tADS tADH tRDS tRDH tACC tMEH tMEl Parameter Address Setup Address Hold Read Cycle Setup Read Cycle Hold Access Time from Posedge ME Minimum ME High Minimum ME Low Minimum 0.6 0.7 0 0 3.4 0.7 0.6 Typical 0.8 0.9 0 0 4.2 0.9 0.8 Maximum 1.1 1.3 0 0 5.9 1.3 1.1 Minimum 0.5 0.6 0 0 2.9 0.6 0.6 Industrial Typical 0.8 0.9 0 0 4.2 0.9 0.8 Maximum 1.2 1.5 0 0 6.9 1.5 1.3 Units ns ns ns ns ns ns ns
Table 50. SRAM Write Cycle Timing Numbers Commercial 3.3V 10%/Industrial 3.3V 10%
Commercial Symbol tADS tADH tWRS tMPW tWDS tWDH Parameter Address Setup Address Hold Write Cycle Setup Minimum Write Duration Data Setup to Write End Data Hold to Write End Minimum 0.6 0.7 0 1.4 4.6 0.6 Typical 0.8 0.9 0 1.8 5.7 0.8 Maximum 1.1 1.3 0 2.5 8.0 1.1 Minimum 0.5 0.6 0 1.2 3.9 0.5 Industrial Typical 0.8 0.9 0 1.8 5.7 0.8 Maximum 1.2 1.5 0 3.0 9.4 1.3 Units ns ns ns ns ns ns
163
Rev. 1138F-FPSLI-06/02
Table 51. FPSLIC Interface Timing Information(1)
3.3V Commercial 10% Symbol tIXG4 tIXG5 tIXC tIXI Parameter Clock Delay From XTAL2 Pad to GCK_5 Access to FPGA Core Clock Delay From XTAL2 Pad to GCK_6 Access to FPGA Core Clock Delay From XTAL2 Pad to AVR Core Clock Clock Delay From XTAL2 Pad to AVR I/O Clock Minimum 3.6 3.9 2.8 3.5 Typical 4.8 5.2 3.7 4.7 Maximum 7.6 8.1 6.3 7.5 3.3V Industrial 10% Minimum 3.4 3.6 2.5 3.2 Typical 4.8 5.2 3.7 4.7 Maximum 7.9 8.8 6.9 7.8 Units ns ns ns ns
tCFIR tCFIW
AVR Core Clock to FPGA I/O Read Enable AVR Core Clock to FPGA I/O Write Enable
5.3 5.2
6.6 6.6
7.9 7.9
4.4 4.4
6.6 6.6
9.2 9.2
ns ns
tCFIS tFIRQ
AVR Core Clock to FPGA I/O Select Active FPGA Interrupt Net Propagation Delay to AVR Core
6.3 0.2
7.8 0.2
9.4 0.3
5.3 0.1
7.8 0.2
11.0 0.3
ns ns
tIFS tFRWS tFAS tFDWS tFDRS Note:
FPGA SRAM Clock to On-chip SRAM FPGA SRAM Write Stobe to On-chip SRAM FPGA SRAM Address Valid to On-chip SRAM Address Valid FPGA Write Data Valid to On-chip SRAM Data Valid On-chip SRAM Data Valid to FPGA Read Data Valid
6.1 4.4 5.4 1.3 0.2
7.7 5.5 6.7 1.7 0.2
7.7 5.5 6.7 2.0 0.2
4.9 3.7 4.3 1.3 0.2
7.7 5.5 6.7 1.7 0.2
7.7 5.5 6.7 2.0 0.2
ns ns ns ns ns
1. Insertion delays are specified from XTAL2. These delays are more meaningful because the XTAL1-to-XTAL2 delay is sensitive to system loading on XTAL2. If it is necessary to drive external devices with the system clock, devices should use XTAL2 output pin. Remember that XTAL2 is inverted in comparison to XTAL1.
164
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
External Clock Drive Waveforms
Figure 85. External Clock Drive Waveforms
VIH1 VIL1
Table 52. External Clock Drive, VCC = 3.0V to 3.6V
Symbol 1/tCLCL tCLCL tCHCX tCLCX tCLCH tCHCL Parameter Oscillator Frequency Clock Period High Time Low Time Rise Time Fall Time Minimum 0 40 15 15 - - Maximum 25 - - - 1.6 1.6 Units MHz ns ns ns s s
165
Rev. 1138F-FPSLI-06/02
AC Timing Characteristics - 3.3V Operation
Delays are based on fixed loads and are described in the notes. Maximum times based on worst case: VCC = 3.00V, temperature = 70C Minimum times based on best case: VCC = 3.60V, temperature = 0C Maximum delays are the average of tPDLH and tPDHL.
Cell Function Core 2 Input Gate 3 Input Gate 3 Input Gate 4 Input Gate Fast Carry Fast Carry Fast Carry Fast Carry Fast Carry Fast Carry Fast Carry Fast Carry DFF DFF DFF DFF DFF DFF incremental -> L Local Output Enable Local Output Enable tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tsetup (Minimum) thold (Minimum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPZX (Maximum) tPXZ (Maximum) x/y -> x/y x/y/z -> x/y x/y/w -> x/y x/y/w/z -> x/y y -> y x -> y y -> x x -> x w -> y w -> x z -> y z -> x q -> x/y x/y -> clk x/y -> clk R -> x/y S -> x/y q -> w x/y -> L oe -> L oe -> L 2.9 2.8 3.4 3.4 2.3 2.9 3.0 2.3 3.4 3.4 3.4 2.4 2.8 - - 3.2 3.0 2.7 2.4 2.8 2.4 ns ns ns ns ns ns ns ns ns ns ns ns ns - - ns ns ns ns ns ns 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load - - 1 Unit Load 1 Unit Load - - 1 Unit Load Parameter Path -25 Units Notes
166
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
AC Timing Characteristics - 3.3V Operation
Delays are based on fixed loads and are described in the notes. Maximum times based on worst case: VCC = 3.0V, temperature = 70C Minimum times based on best case: VCC = 3.6V, temperature = 0C Maximum delays are the average of tPDLH and tPDHL. All input IO characteristics measured from a VIH of 50% of VDD at the pad (CMOS threshold) to the internal VIH of 50% of VDD. All output IO characteristics are measured as the average of tPDLH and tPDHL to the pad VIH of 50% of VDD.
Cell Function Repeaters Repeater Repeater Repeater Repeater Repeater Repeater tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) L -> E E -> E L -> L E -> L E -> IO L -> IO 2.2 2.2 2.2 2.2 1.4 1.4 ns ns ns ns ns ns 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load 1 Unit Load Parameter Path -25 Units Notes
All input IO characteristics measured from a VIH of 50% of VDD at the pad (CMOS threshold) to the internal VIH of 50% of VDD. All output IO characteristics are measured as the average of tPDLH and tPDHL to the pad VIH of 50% of VDD.
Cell Function IO Input Input Input Input Output, Slow Output, Medium Output, Fast Output, Slow Output, Slow Output, Medium Output, Medium Output, Fast Output, Fast tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPZX (Maximum) tPXZ (Maximum) tPZX (Maximum) tPXZ (Maximum) tPZX (Maximum) tPXZ (Maximum) pad -> x/y pad -> x/y pad -> x/y pad -> x/y x/y/E/L -> pad x/y/E/L -> pad x/y/E/L -> pad oe -> pad oe -> pad oe -> pad oe -> pad oe -> pad oe -> pad 1.9 5.8 11.5 17.4 9.1 7.6 6.2 9.5 2.1 7.4 2.7 5.9 2.4 ns ns ns ns ns ns ns ns ns ns ns ns ns No Extra Delay 1 Extra Delay 2 Extra Delays 3 Extra Delays 50 pf Load 50 pf Load 50 pf Load 50 pf Load 50 pf Load 50 pf Load 50 pf Load 50 pf Load 50 pf Load Parameter Path -25 Units Notes
167
Rev. 1138F-FPSLI-06/02
AC Timing Characteristics - 3.3V Operation
Delays are based on fixed loads and are described in the notes. Maximum times based on worst case: VCC = 3.0V, temperature = 70C Minimum times based on best case: VCC = 3.6V, temperature = 0C Maximum delays are the average of tPDLH and tPDHL. Clocks and Reset Input buffers are measured from a VIH of 1.5V at the input pad to the internal VIH of 50% of VCC. Maximum times for clock input buffers and internal drivers are measured for rising edge delays only.
Cell Function Parameter Path Device -25 Units Notes
Global Clocks and Set/Reset GCK Input Buffer tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPD (Maximum) pad -> clock pad -> clock pad -> clock pad -> clock clock -> colclk clock -> colclk colclk -> secclk colclk -> secclk colclk -> secclk colclk -> secclk clock pad -> out clock pad -> out AT94K05 AT94K10 AT94K40 AT94K05 AT94K10 AT94K40 AT94K05 AT94K10 AT94K40 AT94K05 AT94K10 AT94K40 AT94K05 AT94K10 AT94K40 AT94K05 AT94K10 AT94K40 1.2 1.5 1.9 0.7 0.8 0.9 1.3 1.8 2.5 1.0 1.0 1.0 5.4 8.2 12.6 13.4 14.5 ns ns ns ns ns ns ns ns ns ns ns ns Rising Edge Clock
FCK Input Buffer
Rising Edge Clock
Clock Column Driver
Rising Edge Clock
Clock Sector Driver
Rising Edge Clock
GSRN Input Buffer
-
Global Clock to Output
Rising Edge Clock Fully Loaded Clock Tree Rising Edge DFF 20 mA Output Buffer 50 pf Pin Load Rising Edge Clock Fully Loaded Clock Tree Rising Edge DFF 20 mA Output Buffer 50 pf Pin Load
Fast Clock to Output
tPD (Maximum)
clock pad -> out clock pad -> out
AT94K05 AT94K10 AT94K40
12.1 12.7 13.5
ns ns
168
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
AC Timing Characteristics - 3.3V Operation
Delays are based on fixed loads and are described in the notes. Maximum times based on worst case: VCC = 3.0V, temperature = 70C Minimum times based on best case: VCC = 3.6V, temperature = 0C
Cell Function Async RAM Write Write Write Write Write Write Write Write Write/Read Read Read Read Sync RAM Write Write Write Write Write Write Write Write Write Write/Read Write/Read Read Read Read tCYC (Minimum) tCLKL (Minimum) tCLKH (Minimum) tsetup (Minimum) thold (Minimum) tsetup (Minimum) thold (Minimum) tsetup (Minimum) thold (Minimum) tPD (Maximum) tPD (Maximum) tPD (Maximum) tPZX (Maximum) tPXZ (Maximum) cycle time clk clk we setup-> clk we hold -> clk wr addr setup-> clk wr addr hold -> clk wr data setup-> clk wr data hold -> clk din -> dout clk -> dout rd addr -> dout oe -> dout oe -> dout 12.0 5.0 5.0 3.2 0.0 5.0 0.0 3.9 0.0 8.7 5.8 6.3 2.9 3.5 ns ns ns ns ns ns ns ns ns ns ns ns ns ns - - rd addr = wr addr rd addr = wr addr - - - Pulse Width High tWECYC (Minimum) tWEL (Minimum) tWEH (Minimum) tsetup (Minimum) thold (Minimum) tsetup (Minimum) thold (Minimum) thold (Minimum) tPD (Maximum) tPD (Maximum) tPZX (Maximum) tPXZ (Maximum) cycle time we we wr addr setup-> we wr addr hold -> we din setup -> we din hold -> we oe hold -> we din -> dout rd addr -> dout oe -> dout oe -> dout 12.0 5.0 5.0 5.3 0.0 5.0 0.0 0.0 8.7 6.3 2.9 3.5 ns ns ns ns ns ns ns ns ns ns ns ns - rd addr = wr addr - - - Pulse Width Low Pulse Width High Parameter Path -25 Units Notes
CMOS buffer delays are measured from a VIH of 1/2 VCC at the pad to the internal VIH at A. The input buffer load is constant. Buffer delay is to a pad voltage of 1.5V with one output switching. Parameter based on characterization and simulation; not tested in production. An FPGA power calculation is available in Atmel's System Designer software (see also page 160).
169
Rev. 1138F-FPSLI-06/02
Packaging and Pin List Information
FPSLIC devices should be laid out to support a split power supply for both AL and AX families. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note, available on the Atmel web site. Table 53. Part and Package Combinations Available
Part # PLCC 84 TQ 100 LQ144 PQ 208 Package AJ AQ BQ DQ AT94K05 46 58 82 96 AT94K10 46 58 84 116 84 120 AT94K40
Table 54. AT94K JTAG ICE Pin List
Pin TDI TDO TMS TCK AT94K05 96 FPGA I/O IO34 IO38 IO43 IO44 AT94K10 192 FPGA I/O IO50 IO54 IO63 IO64 AT94K40 384 FPGA I/O IO98 IO102 IO123 IO124
Table 55. AT94K Pin List
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O West Side GND I/O1, GCK1 (A16) I/O2 (A17) I/O3 I/O4 I/O5 (A18) I/O6 (A19) GND I/O1, GCK1 (A16) I/O2 (A17) I/O3 I/O4 I/O5 (A18) I/O6 (A19) GND I/O1, GCK1 (A16) I/O2 (A17) I/O3 I/O4 I/O5 (A18) I/O6 (A19) GND I/O7 I/O8 I/O9 15 16 4 5 12 13 14 1 2 3 1 2 3 4 5 6 7 2 4 5 6 7 8 9 Packages PC84 TQ100 PQ144 PQ208
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
170
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O I/O10 I/O11 I/O12 VCC(1) GND I/O13 I/O14 I/O7 I/O8 I/O7 I/O8 I/O9 I/O10 I/O15 I/O16 I/O17 I/O18 GND I/O19 I/O20 I/O11 I/O12 I/O21 I/O22 I/O23 I/O24 GND I/O9, FCK1 I/O10 I/O11 (A20) I/O12 (A21) GND I/O13, FCK1 I/O14 I/O15 (A20) I/O16 (A21) VCC
(1)
Packages PC84 TQ100 PQ144 PQ208
10 11 12 13
GND I/O25, FCK1 I/O26 I/O27 (A20) I/O28 (A21) VCC
(1)
8 9 10 17 18 6 7 11 12
14 15 16 17 18
I/O17 I/O18
I/O29 I/O30 GND I/O31 I/O32 I/O33 I/O34 I/O35 I/O36 GND
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
171
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O VCC
(1)
Packages PC84 TQ100 PQ144 PQ208
I/O37 I/O38 I/O39 I/O40 I/O19 I/O20 I/O41 I/O42 GND I/O13 I/O14 I/O21 I/O22 I/O43 I/O44 I/O45 I/O46 I/O15 (A22) I/O16 (A23) GND VDD
(2)
19 20
13 8 14
21 22
I/O23 (A22) I/O24 (A23) GND VDD
(2)
I/O47 (A22) I/O48 (A23) GND VDD
(2)
19 20 21 22 23 24
9 10 11 12 13 14
15 16 17 18 19 20
23 24 25 26 27 28
I/O17 (A24) I/O18 (A25)
I/O25 (A24) I/O26 (A25)
I/O49 (A24) I/O50 (A25) I/O51 I/O52
I/O19 I/O20
I/O27 I/O28
I/O53 I/O54 GND
15
21 22
29 30
I/O29 I/O30
I/O55 I/O56 I/O57 I/O58 I/O59 I/O60 VCC(1) GND I/O61 I/O62 I/O63
31 32
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
172
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O I/O64 I/O65 I/O66 GND I/O31 I/O32 VDD I/O21 (A26) I/O22 (A27) I/O23 I/O24, FCK2 GND
(2)
Packages PC84 TQ100 PQ144 PQ208
I/O67 I/O68 VDD(2) I/O69 (A26) I/O70 (A27) I/O71 I/O72, FCK2 GND I/O73 I/O74 25 26 16 17 23 24 25 26 27 33 34 35 36 37
I/O33 (A26) I/O34 (A27) I/O35 I/O36, FCK2 GND
I/O37 I/O38
I/O75 I/O76 I/O77 I/O78 GND I/O79 I/O80
I/O39 I/O40 I/O25 I/O26 I/O41 I/O42
I/O81 I/O82 I/O83 I/O84 GND VCC(1) I/O85 I/O86 I/O87 I/O88
38 39 40 41
I/O27 (A28) I/O28
I/O43 (A28) I/O44
I/O89 (A28) I/O90 GND
27
18 19
28 29
42 43
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
173
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O I/O91 I/O92 I/O29 I/O30 I/O31 (OTS) I/O32, GCK2 (A29) AVRRESET GND M0 I/O45 I/O46 I/O47 (OTS) I/O48, GCK2 (A29) AVRRESET GND M0 I/O93 I/O94 I/O95 (OTS) I/O96, GCK2 (A29) AVRRESET GND M0 28 29 30 31 32 20 21 22 23 24 30 31 32 33 34 35 36 44 45 46 47 48 49 50 Packages PC84 TQ100 PQ144 PQ208
South Side
VCC
(1)
VCC
(1)
VCC(1) M2 I/O97, GCK3 I/O98 (HDC/TDI) I/O99 I/O100 I/O101 I/O102 (LDC/TDO) GND I/O103 I/O104 I/O105 I/O106 I/O107 I/O108 VCC(1) GND
33 34 35 36
25 26 27 28
37 38 39 40 41 42
55 56 57 58 59 60 61
M2 I/O33, GCK3 I/O34 (HDC/TDI) I/O35 I/O36 I/O37 Not a User I/O I/O38 (LDC/TDO)
M2 I/O49, GCK3 I/O50 (HDC/TDI) I/O51 I/O52 I/O53 Not a User I/O I/O54 (LDC/TDO)
29
43
37
30
44
62
I/O39 I/O40
I/O55 I/O56 I/O57 I/O58
I/O109 I/O110 I/O111 I/O112
63 64 65 66
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
174
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O I/O113 I/O114 GND I/O115 I/O116 I/O59 I/O60 I/O117 I/O118 I/O119 I/O120 GND I/O41 I/O42 I/O43/TMS I/O44/TCK GND I/O61 I/O62 I/O63/TMS I/O64/TCK VCC
(1)
Packages PC84 TQ100 PQ144 PQ208
GND I/O121 I/O122 I/O123/TMS I/O124/TCK VCC
(1)
45 46 47 38 39 31 32 48 49
67 68 69 70 71
I/O65 I/O66
I/O125 I/O126 GND I/O127 I/O128 I/O129 I/O130 I/O131 I/O132 GND VCC(1) I/O133 I/O134
72 73
I/O67 I/O68 I/O45 I/O46 I/O69 I/O70
I/O135 I/O136 I/O137 I/O138 GND I/O139 33 34 50 51 74 75
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
175
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O I/O140 I/O141 I/O142 I/O47 (TD7) I/O48 (InitErr) VDD
(2)
Packages PC84 TQ100 PQ144 PQ208
I/O71 (TD7) I/O72 (InitErr) VDD
(2)
I/O143 (TD7) I/O144 (InitErr) VDD
(2)
40 41 42 43 44 45
35 36 37 38 39 40
52 53 54 55 56 57
76 77 78 79 80 81
GND I/O49 (TD6) I/O50 (TD5)
GND I/O73 (TD6) I/O74 (TD5)
GND I/O145 (TD6) I/O146 (TD5) I/O147 I/O148 I/O149 I/O150 GND
I/O51 I/O52
I/O75 I/O76 I/O77 I/O78
I/O151 I/O152 I/O153 I/O154 I/O155 I/O156 VCC(1) GND I/O157 I/O158 I/O159 I/O160 I/O161 I/O162 GND
41 42
58 59
82 83 84 85
I/O79 I/O80 VCC I/O53 (TD4) I/O54 (TD3)
(1)
I/O163 I/O164 VCC(1) I/O165 (TD4) I/O166 (TD3) 46 47 43 44 60 61 86 87
I/O81 (TD4) I/O82 (TD3)
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
176
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O I/O55 I/O56 GND AT94K10 192 FPGA I/O I/O83 I/O84 GND AT94K40 384 FPGA I/O I/O167 I/O168 GND I/O169 I/O170 I/O85 I/O86 I/O171 I/O172 I/O173 I/O174 GND I/O175 I/O176 I/O87 I/O88 I/O57 I/O58 I/O89 I/O90 I/O177 I/O178 I/O179 I/O180 GND VCC(1) I/O181 I/O182 I/O59 (TD2) I/O60 (TD1) I/O91 (TD2) I/O92 (TD1) I/O183 (TD2) I/O184 (TD1) I/O185 I/O186 GND I/O187 I/O188 I/O61 I/O62 I/O63 (TD0) I/O64, GCK4 GND CON I/O93 I/O94 I/O95 (TD0) I/O96, GCK4 GND CON I/O189 I/O190 I/O191 (TD0) I/O192, GCK4 GND CON East Side 50 51 52 53 47 48 49 50 67 68 69 70 71 72 97 98 99 100 101 103 48 49 45 46 65 66 95 96 91 92 93 94 Packages PC84 TQ100 PQ144 62 63 64 PQ208 88 89 90
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
177
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O VCC
(1)
AT94K10 192 FPGA I/O VCC
(1)
AT94K40 384 FPGA I/O VCC
(1)
Packages PC84 54 55 56 57 TQ100 51 52 53 54 PQ144 73 74 75 76 77 78 PQ208 106 108 109 110 111 112
RESET PE0 PE1 PD0 PD1
RESET PE0 PE1 PD0 PD1
RESET PE0 PE1 PD0 PD1 GND VCC(1) GND
PE2 PD2
PE2 PD2
PE2 PD2 GND
58
55 56
79 80
113 114
No Connect PD3 PD4
No Connect PD3 PD4 VCC
(1)
No Connect PD3 PD4 VCC
(1)
81 82 83
119 120 121
PE3 CS0, Cs0n
PE3 CS0, Cs0n
PE3 CS0, Cs0n GND GND VCC(1)
59 60
57 58
84 85
122 123
SDA SCL
SDA SCL
SDA SCL GND
124 125
PD5 PD6 PE4 PE5 VDD
(2)
PD5 PD6 PE4 PE5 VDD
(2)
PD5 PD6 PE4 PE5 VDD
(2)
59 60 61 62 63 64 65 66 61 62 63 64 65 66 67
86 87 88 89 90 91 92 93 94
126 127 128 129 130 131 132 133 134
GND PE6 PE7 (CHECK) PD7
GND PE6 PE7 (CHECK) PD7
GND PE6 PE7 (CHECK) PD7
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
178
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O INTP0 AT94K10 192 FPGA I/O INTP0 AT94K40 384 FPGA I/O INTP0 GND VCC(1) GND GND XTAL1 XTAL2 XTAL1 XTAL2 VDD RX0 TX0 GND
(2)
Packages PC84 TQ100 PQ144 95 PQ208 135
XTAL1 XTAL2 VDD
(2)
67 68
68 69
96 97
138 139
RX0 TX0 GND
RX0 TX0 GND GND
98 99 100
140 141 142
INTP1 INTP2
INTP1 INTP2
INTP1 INTP2 GND VCC(1)
145 146
TOSC1 TOSC2
TOSC1 TOSC2
TOSC1 TOSC2 GND
69 70
70 71
101 102
147 148
RX1 TX1 D0 INTP3 (CSOUT) CCLK VCC
(1)
RX1 TX1 D0 INTP3 (CSOUT) CCLK VCC
(1)
RX1 TX1 D0 INTP3 (CSOUT) CCLK VCC
(1)
103 104 71 72 73 74 72 73 74 75 105 106 107 108
149 150 151 152 153 154
I/O65:95 Are Unbonded(3)
I/O97:144 Are Unbonded(3)
I/O193:288 Are Unbonded(3) North Side
Testclock GND I/O97 (A0) I/O98, GCK7 (A1) I/O99
Testclock GND I/O145 (A0) I/O146, GCK7 (A1) I/O147
Testclock GND I/O289 (A0) I/O290, GCK7 (A1) I/O291
75 76 77 78
76 77 78 79
109 110 111 112 113
159 160 161 162 163
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
179
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O I/O100 AT94K10 192 FPGA I/O I/O148 AT94K40 384 FPGA I/O I/O292 I/O293 I/O294 GND I/O295 I/O296 I/O101 (CS1, A2) I/O102 (A3) I/O149 (CS1, A2) I/O150 (A3) I/O297 (CS1, A2) I/O298 (A3) I/O299 I/O300 VCC(1) GND I/O104 I/O151 I/O152 I/O103 I/O153 I/O154 I/O301 I/O302 I/O303 I/O304 I/O305 I/O306 GND I/O307 I/O308 I/O155 I/O156 I/O309 I/O310 I/O311 I/O312 GND I/O105 I/O106 GND I/O157 I/O158 I/O159 I/O160 VCC
(1)
Packages PC84 TQ100 PQ144 114 PQ208 164
79 80
80 81
115 116
165 166
Shorted to Testclock
Shorted to Testclock
Shorted to Testclock
Shorted to Testclock
117
167 168
169 170
GND I/O313 I/O314 I/O315 I/O316 VCC(1) I/O317 I/O318
118 119 120
171 172 173
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
180
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O GND I/O319 I/O320 I/O321 I/O322 I/O323 I/O324 GND VCC(1) I/O107 (A4) I/O108 (A5) I/O161 (A4) I/O162 (A5) I/O325 (A4) I/O326 (A5) GND I/O163 I/O164 I/O109 I/O110 I/O165 I/O166 I/O327 I/O328 I/O329 I/O330 GND I/O331 I/O332 I/O333 I/O334 I/O111 (A6) I/O112 (A7) GND VDD
(2)
Packages PC84 TQ100 PQ144 PQ208
81 82
82 83
121 122
174 175
176 177 84 85 123 124 178 179
I/O167 (A6) I/O168 (A7) GND VDD
(2)
I/O335 (A6) I/O336 (A7) GND VDD
(2)
83 84 1 2 3 4
86 87 88 89 90 91
125 126 127 128 129 130
180 181 182 183 184 185
I/O113 (A8) I/O114 (A9)
I/O169 (A8) I/O170 (A9)
I/O337 (A8) I/O338 (A9) I/O339 I/O340 I/O341 I/O342 GND
I/O115 I/O116
I/O171 I/O172
I/O343 I/O344
92 93
131 132
186 187
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
181
Rev. 1138F-FPSLI-06/02
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O I/O173 I/O174 I/O117 (A10) I/O118 (A11) I/O175 (A10) I/O176 (A11) AT94K40 384 FPGA I/O I/O345 I/O346 I/O347 (A10) I/O348 (A11) VCC
(1)
Packages PC84 TQ100 PQ144 PQ208 188 189 5 6 94 95 133 134 190 191
GND I/O349 I/O350 I/O351 I/O352 I/O353 I/O354 GND I/O355 I/O356 VDD
(2)
VDD(2) I/O357 I/O358 I/O359 I/O360 GND I/O361 I/O362 135 136 137 192 193 194
I/O177 I/O178 I/O119 I/O120 GND I/O179 I/O180 GND
I/O181 I/O182
I/O363 I/O364 I/O365 I/O366 GND I/O367 I/O368
195 196
I/O121 I/O122 I/O123 (A12) I/O124 (A13)
I/O183 I/O184 I/O185 (A12) I/O186 (A13)
I/O369 I/O370 I/O371 (A12) I/O372 (A13) 7 8 96 97 138 139
197 198 199 200
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
182
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table 55. AT94K Pin List (Continued)
AT94K05 96 FPGA I/O AT94K10 192 FPGA I/O AT94K40 384 FPGA I/O GND VCC(1) I/O373 I/O374 I/O375 I/O376 I/O377 I/O378 GND I/O187 I/O188 I/O125 I/O126 I/O127 (A14) I/O128, GCK8 (A15) VCC (1) I/O189 I/O190 I/O191 (A14) I/O192, GCK8 (A15) VCC(1) I/O379 I/O380 I/O381 I/O382 I/O383 (A14) I/O384, GCK8 (A15) VCC(1) 9 10 11 98 99 100 140 141 142 143 144 201 202 203 204 205 Packages PC84 TQ100 PQ144 PQ208
Notes:
1. VCC is I/O high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 2. VDD is core high voltage. Please refer to the "Designing in Split Power Supply Support for AT94KAL/AX and AT94SAL/AX Devices" application note. 3. Unbonded pins are No Connects.
183
Rev. 1138F-FPSLI-06/02
Ordering Information
Usable Gates 5,000 Speed Grade -25 MHz Ordering Code AT94K05AL-25AJC AT94K05AL-25AQC AT94K05AL-25BQC AT94K05AL-25DQC AT94K05AL-25AJI AT94K05AL-25AQI AT94K05AL-25BQI AT94K05AL-25DQI 10,000 -25 MHz AT94K10AL-25AJC AT94K10AL-25AQC AT94K10AL-25BQC AT94K10AL-25DQC AT94K10AL-25AJI AT94K10AL-25AQI AT94K10AL-25BQI AT94K10AL-25DQI 40,000 -25 MHz AT94K40AL-25BQC AT94K40AL-25DQC AT94K40AL-25BQI AT94K40AL-25DQI Package 84J 100A 144L1 208Q1 84J 100A 144L1 208Q1 84J 100A 144L1 208Q1 84J 100A 144L1 208Q1 144L1 208Q1 144L1 208Q1 Operation Range Commercial (0C - 70C)
Industrial (-40C - 85C)
Commercial (0C - 70C)
Industrial (-40C - 85C)
Commercial (0C - 70C) Industrial (-40C - 85C)
Package Type 84J 100A 144L1 208Q1 84-lead, Plastic J-leaded Chip Carrier (PLCC) 100-lead, Thin (1.0 mm) Plastic Quad Flat Package (TQFP) 144-lead, Low Profile Plastic Gull Wing Quad Flat Package (LQFP) 208-lead, Plastic Gull Wing Quad Flat Package (PQFP)
184
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Packaging Information
84J - PLCC
1.14(0.045) X 45
PIN NO. 1 IDENTIFIER
1.14(0.045) X 45 0.318(0.0125) 0.191(0.0075)
E1 B
E
B1
D2/E2
e D1 D A A2 A1
0.51(0.020)MAX 45 MAX (3X)
COMMON DIMENSIONS (Unit of Measure = mm) SYMBOL A A1 A2 D D1 E Notes: 1. This package conforms to JEDEC reference MS-018, Variation AF. 2. Dimensions D1 and E1 do not include mold protrusion. Allowable protrusion is .010"(0.254 mm) per side. Dimension D1 and E1 include mold mismatch and are measured at the extreme material condition at the upper or lower parting line. 3. Lead coplanarity is 0.004" (0.102 mm) maximum. E1 D2/E2 B B1 e MIN 4.191 2.286 0.508 30.099 29.210 30.099 29.210 27.686 0.660 0.330 NOM - - - - - - - - - - 1.270 TYP MAX 4.572 3.048 - 30.353 29.413 30.353 29.413 28.702 0.813 0.533 Note 2 Note 2 NOTE
10/04/01 2325 Orchard Parkway San Jose, CA 95131 TITLE 84J, 84-lead, Plastic J-leaded Chip Carrier (PLCC) DRAWING NO. 84J REV. B
R
185
Rev. 1138F-FPSLI-06/02
100A - TQFP
PIN 1 B
PIN 1 IDENTIFIER
e
E1
E
D1 D C
0~7 A1 L
COMMON DIMENSIONS (Unit of Measure = mm) SYMBOL A A1 A2 D D1 E MIN - 0.05 0.95 15.75 13.90 15.75 13.90 0.17 0.09 0.45 NOM - - 1.00 16.00 14.00 16.00 14.00 - - - 0.50 TYP MAX 1.20 0.15 1.05 16.25 14.10 16.25 14.10 0.27 0.20 0.75 Note 2 Note 2 NOTE
A2
A
Notes:
1. This package conforms to JEDEC reference MS-026, Variation AED. 2. Dimensions D1 and E1 do not include mold protrusion. Allowable protrusion is 0.25 mm per side. Dimensions D1 and E1 are maximum plastic body size dimensions including mold mismatch. 3. Lead coplanarity is 0.08 mm maximum.
E1 B C L e
10/5/2001 2325 Orchard Parkway San Jose, CA 95131 TITLE 100A, 100-lead, 14 x 14 mm Body Size, 1.0 mm Body Thickness, 0.5 mm Lead Pitch, Thin Profile Plastic Quad Flat Package (TQFP) DRAWING NO. 100A REV. C
R
186
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
144L1 - LQFP
D1
D
XX
e
E1
E
CO
U NT
RY
b
Bottom View Top View
COMMON DIMENSIONS (Unit of Measure = mm) SYMBOL MIN 0.05 1.35 1.40 22.00 BSC 20.00 BSC 22.00 BSC 20.00 BSC 0.50 BSC 0.17 0.22 1.00 REF 0.27 4, 5 2, 3 2, 3 NOM MAX 0.15 1.45 NOTE 6
A2 A1 L1
A1 A2 D D1 E
Side View
E1 e b L1
Notes: 1. This drawing is for general information only; refer to JEDEC Drawing MS-026 for additional information. 2. The top package body size may be smaller than the bottom package size by as much as 0.15 mm. 3. Dimensions D1 and E1 do not include mold protrusions. Allowable protrusion is 0.25 mm per side. D1 and E1 are maximum plastic body size dimensions including mold mismatch. 4. Dimension b does not include Dambar protrusion. Allowable Dambar protrusion shall not cause the lead width to exceed the maximum b dimension by more than 0.08 mm. Dambar cannot be located on the lower radius or the foot. Minimum space between protrusion and an adjacent lead is 0.07 mm for 0.4 and 0.5 mm pitch packages. 5. These dimensions apply to the flat section of the lead between 0.10 mm and 0.25 mm from the lead tip. 6. A1 is defined as the distance from the seating place to the lowest point on the package body.
11/30/01 REV. A
R
2325 Orchard Parkway San Jose, CA 95131
TITLE 144L1, 144-lead (20 x 20 x 1.4 mm Body), Low Profile Plastic Quad Flat Pack (LQFP)
DRAWING NO. 144L1
187
Rev. 1138F-FPSLI-06/02
208Q1 - PQFP
D1
A2 L1 E1 A1
Side View
e b
Top View
D
COMMON DIMENSIONS (Unit of Measure = mm) SYMBOL A1 A2 MIN 0.25 3.20 3.40 30.60 BSC 28.00 BSC 30.60 BSC 28.00 BSC 0.50 BSC 0.17 1.30 REF 0.27 4 2, 3 2, 3 NOM MAX 0.50 3.60 NOTE
E
D D1 E E1 e b L1
Bottom View
Notes: 1. This drawing is for general information only; refer to JEDEC Drawing MO-153, Variation AA, for proper dimensions, tolerances, datums, etc. 2. The top package body size may be smaller than the bottom package size by as much as 0.15 mm. 3. Dimensions D1 and E1 do not include mold protrusions. Allowable protrusion is 0.25 mm per side. D1 and E1 are maximum plastic body size dimensions including mold mismatch. 4. Dimension b does not include Dambar protrusion. Allowable Dambar protrusion shall not cause the lead width to exceed the maximum b dimension by more than 0.08 mm. Dambar cannot be located on the lower radius or the foot. Minimum space between protrusion and an adjacent lead is 0.07 mm.
11/30/01 2325 Orchard Parkway San Jose, CA 95131 TITLE 208Q1, 208-lead (28 x 28 mm Body, 2.6 Form Opt.), Plastic Quad Flat Pack (PQFP) DRAWING NO. 208Q1 REV. A
R
188
AT94K Series FPSLIC
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Thermal Coefficient Table
Package Style PLCC TQFP LQFP PQFP Lead Count 84 100 144 208 Theta J-A 0 LFPM 37 47 33 32 Theta J-A 225 LFPM 30 39 27 28 Theta J-A 500 LPFM 25 33 23 24 Theta J-C 12 22 8.5 10
189
Rev. 1138F-FPSLI-06/02
AT94K Series FPSLIC
Table of Contents
Features................................................................................................. 1 Description ............................................................................................ 2 FPGA Core............................................................................................. 5
Fast, Flexible and Efficient SRAM ........................................................................ 5 Fast, Efficient Array and Vector Multipliers ........................................................... 5 Cache Logic Design.............................................................................................. 5 Automatic Component Generators ....................................................................... 5 The Symmetrical Array ......................................................................................... 5 The Busing Network ............................................................................................. 6 Cell Connections................................................................................................... 8 The Cell ................................................................................................................ 8 RAM.................................................................................................................... 10 Clocking and Set/Reset ...................................................................................... 14
FPGA/AVR Interface and System Control ........................................ 21
FPGA/AVR Interface- Memory-mapped Peripherals ......................................... Program and Data SRAM .................................................................................................................. Data SRAM Access by FPGA - FPGAFrame Mode .......................................... SRAM Access by FPGA/AVR .............................................................................................................. AVR Cache Mode ............................................................................................... Resets................................................................................................................. System Control ................................................................................................... 21 22 24 24 29 29 30
AVR Core and Peripherals ................................................................. 34
Instruction Set Nomenclature (Summary)........................................................... Complete Instruction Set Summary .................................................................... Pin Descriptions.................................................................................................. Clock Options ..................................................................................................... Architectural Overview ........................................................................................ General-purpose Register File............................................................................ X-register, Y-register and Z-register ...................................................................................................................... ALU - Arithmetic Logic Unit................................................................................ Multiplier Unit ...................................................................................................... SRAM Data Memory........................................................................................... Memory-mapped I/O........................................................................................... Software Control of System Configuration.......................................................... FPGA Cache Logic ............................................................................................. 35 36 40 41 42 43
44 44 44 44 47 51 53
i
1138F-FPSLI-06/02
FPGA I/O Selection by AVR ............................................................................... 53 FPGA I/O Interrupt Control by AVR .................................................................... 57 Reset and Interrupt Handling .............................................................................. 58 Sleep Modes....................................................................................................... 66 JTAG Interface and On-chip Debug System ...................................................... 68 IEEE 1149.1 (JTAG) Boundary-scan ............................................................................................................. 73 Bypass Register.................................................................................................. 74 Device Identification Register ............................................................................. 74 AVR Reset Register............................................................................................ 75 Timer/Counters ................................................................................................... 85 Timer/Counter Prescalers ................................................................................... 85 8-bit Timers/Counters T/C0 and T/C2................................................................. 86 Timer/Counter1................................................................................................... 95 Watchdog Timer ............................................................................................... 104 Multiplier ........................................................................................................... 106 UARTs .............................................................................................................. 119 2-wire Serial Interface (Byte Oriented) ........................................................................................................... 130 I/O Ports............................................................................................................ 147
AC & DC Timing Characteristics ..................................................... 159
Absolute Maximum Ratings*(1).......................................................................... 159 DC and AC Operating Range - 3.3V Operation ............................................... 159
Power-On Power Supply Requirements ......................................... 161
FPSLIC Dual-port SRAM Characteristics ......................................................... 162 External Clock Drive Waveforms ...................................................................... 165
Packaging and Pin List Information................................................ 170 Packaging Information ..................................................................... 185
84J - PLCC ...................................................................................................... 100A - TQFP.................................................................................................... 144L1 - LQFP .................................................................................................. 208Q1 - PQFP ................................................................................................. 185 186 187 188
Table of Contents .................................................................................. i
ii
AT94K Series FPSLIC
1138F-FPSLI-06/02
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Available on web site
(c) Atmel Corporation 2002. Atmel Corporation makes no warranty for the use of its products, other than those expressly contained in the Company's standard warranty which is detailed in Atmel's Terms and Conditions located on the Company's web site. The Company assumes no responsibility for any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of Atmel are granted by the Company in connection with the sale of Atmel products, expressly or by implication. Atmel's products are not authorized for use as critical components in life support devices or systems.
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Rev. 1138F-FPSLI-06/02

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