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W89C940 elanc-pci (twisted-pair ether-lan controller with pci interface) general description he elanc-pci (twisted-pair ether-lan controller with pci interface) integrates a w89c902 serial(elanc- pci) lan coprocessor for twisted-pair (slct) and pc/at pci bus interface logic into a single chip. the elanc-pci provides an easy way of implementing the interface between an ieee 802.3-compatible ethernet and a personal computer, elanc-pci also provide fast dma operation to improve the packet transmit and receive performance. the pci bus is a high performance local bus architecture with low latency random access time. it is a synchronous bus with operation up to 33mhz. the pci bus interface is designed to provide the registers with the device information required for configuration, recording the status of the lines , control registers, interrupt line and i/o base address registers. it is capable of functioning in a half-duplex environment. the W89C940fis designed to fully comply with the standard of pci 2.0 specification. taking advantage of pci's nature, W89C940f supports auto-configuration function to free users' depression and confusion on tunning system resources conflict. with extremely high throughput on pci bus, W89C940f offers a 32 bits data path to highly boost its performance without extra cost. comparing with lan card with isa bus, its improvement is excellent. besides, it also supports up to 256kb flash memory reserved for various applications, for instance anti-virus, popular drivers, boot rom, viewing your pc assets...etc., and what is more, these software are able to be updated on line. this can increase more niche feature on your lan card, help you get more and bright your company profile. W89C940f is a single chip - build-in pci bus interface and all necessary circuits - which will let design and board assembly become easy. features ? fully compatible with ieee 802.3 standard ? software compatible with novell ne2000 ? complies with pci local bus specification revision 2.0 ? slave mode for pci bus ? fast dma operation enhancing network access performance ? aui, utp interface available ? supports one chip 32kx8 and 16kx8 sram ? supports up to 64kb boot rom ? eeprom auto-load function after power on reset ? eeprom on-board programming function available ? utp interface polarity auto detection correction function available ? utp/bnc auto media-switching function provided ? led displaying for network segment link/activity status ? signature register available for device identification ? single 5v power supply with low power consumption ? 100 pin pqfp
W89C940 2 pin configuration 50 5 1 5 2 5 3 5 4 5 5 5 6 5 7 5 8 5 9 6 0 6 1 6 2 6 3 6 4 6 5 6 6 6 7 6 8 6 9 7 0 7 1 7 2 7 3 7 4 81 7 5 7 6 7 7 7 8 7 9 8 0 82 83 84 85 86 87 88 89 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 90 91 92 93 94 95 96 97 98 99 100 123456 1 0 1 1 789 1 2 1 3 1 4 1 5 1 6 1 7 1 8 1 9 2 0 2 1 2 2 2 3 2 4 2 5 2 6 2 7 2 8 2 9 3 0 33 32 31 v c c a d 2 2 a d 2 1 a d 2 0 a d 1 9 a d 1 8 a d 1 7 a d 1 6 a d 1 5 c b e # 2 / f r a m # e i r d y # t r d y # d e v s e l # s t o p # g n d v c c p a r c # b e # 1 a d 1 4 a d 1 3 a d 1 2 a d 1 1 a d 1 0 a d 9 a d 8 c / b e # 0 b u s c l k g n d v c c d n g p x t n x t n x r p d c p x r n d ca c t e e c s b p c s b r c s b m s a 1 4 \ l m s a 1 3 m s a 1 2 m s a 1 1 m s a m m 1 0 s a m s a m s a m s a m s a m s a m s a m s a m s a s a 9 8 7 6 5 4 3 2 1 0 v c c x 1 x 2 g n d tpdp tpdm xrdp xrdm dgnd rst# inta ad31 ad30 ad29 ad28 ad27 ad26 ad25 ad24 ad23 c/be3# idsel dgnd mswrb msrdb msd7 msd6 msd5 msd4 msd3 msd2 msd1 msd0 ad0 ad1 ad2 ad3 ad4 ad5 ad6 ad7 dgnd dvcc W89C940(100 pins) # avcc dd d d d d d a
W89C940 3 block diagram h o s t b u s config. registers interrupt control logic pci and interface logic local bus arbitrator buffer memory control eeprom control logic boot rom control logic b u s slct module data buffer m e m o r y sram btrom eeprom aui tpi
W89C940 4 pin description pci interface name number type description clk 29 in clock: bus clock from pci bus. all of the pci signals, except rst#, are synchronized by rising edge of clock. the allowable operating frequency of clk for W89C940 is from 25mhz to 33mhz. rst# 87 in reset: asynchronous reset signal from pci bus. ad[31:00] ad31- ad24 ad23 ad22- ad16 ad15-ad8 ad7-ad0 89 - 96 99 2 - 8 19 - 26 33 - 40 t/s address and data: bidirection bus for pci address and data signals transaction. ad[31:00] is a time division bus. two phases are used to carry the address and data messages of pci bus. the address phase is the clock cycle in which frame# is aeerted. ad[31:24] contains the most significant byte(msb) and the ad[7:0] contain the least significant byte(lsb) during the data phase. the data written from host should be stable and valid when irdy# is asserted. the data driven by W89C940 will be stable and valid when trdy# is asserted. c/be[3:0]# c/be3# c/be2# c/be1# c/be0# 97 9 18 27 t/s in bus command and byte enables: c/be[3:0]# define the type of bus command during the address phase and the byte enables during the data phase of a transaction. there are 16 types of bus command defined in pci bus. four bits of c/be[3:0]# are used to decode the 16 types of bus command. the byte enable determine which byte lanes carry meaningful data. c/be0# indicate the byte 0(ad[7:0]) is valid. c/be1# indicate the byte 1(ad[15:8]) is valid. c/be2# indicate the byte 2(ad[23:16]) is valid. c/be3# indicate the byte 3(ad[32:24]) is valid. par 17 t/s parity: even parity across ad[31:0] and c_be[3:0]b. W89C940 will drive the par in read data phase. the host drives the par for address phase and writes data phase. par is stable and valid one clock after the address phase. par is stable and valid one clock after either irdy# is asserted on a write transaction or trdy# is asserted on a read transaction. once par is valid, it remains valid until one clock after the completion of the current data phase. frame# 10 s/t/s in cycle frame: frame# is asserted by host to indicate the beginning of a bus transaction. when frame# is deasserted, the transaction is in the final data phase.
W89C940 5 pci interface name number type description irdy# 11 s/t/s in initiator ready: initiator ready indicates the host's ability to complete the current data phase of transaction. during a write cycle, irdy# indicates that valid data is presented on ad[31:00]. during a read cycle, it indicates the master is ready to accept the data. the wait cycles are inserted till irdy# and trdy# are asserted at the same cycle. trdy# 12 s/t/s target ready: target ready indicates the W89C940's ability to complete the current data phase of transaction. during a read cycle, trdy# indicates that valid data is presented on ad[31:00]. during a write cycle, it indicates the W89C940 is ready to accept the data. the wait cycles are inserted till both irdy# and trdy# are asserted at the same cycle. stop# 14 s/t/s stop: stop indicates W89C940 is requesting the master to stop the current transaction. idsel 98 in initialization device select: idsel is used as a chip select during pci configuration read and write transaction. devsel# 13 s/t/s device select: devsel# will be asserted when W89C940 decode the correct address. inta# 88 o/d interrupt request: inta# is used to request an interrupt service. the interrupt signal can be masked by the register of imr( interrupt mask register). inta# status is kept at isr( interrupt status register). network interface name number type description x1 x2 53 52 i/ttl o/ttl crystal or oscillator input. crystal or oscillator input (x1) and output (x2) pin. if a crystal is used, it should be connected directly to x1 and x2. if an oscillator is selected, x1 is the 20 mhz input and x2 should be left floating. txp txn 75 74 o/aui aui transmit output: aui differential output pair. the data transmitted by dte will be sent through txp and txn in a differential signal with manchest code format. a 270 ohm pull-down resistor is required for each of txp and txn. txp and txn should be isolated by a pulse transformer from directly connecting outside loop.
W89C940 6 network interface name number type description rxp rxn 79 78 i/aui aui receive input: aui differential input pair. the data received by network transceiver will be sent back through rxp and rxn in a differential signal format. the rxp and rxn are also should be isolated by a pulse transformer. cdp cdn 77 76 i/aui aui collision input: aui differential input pair. the network transceiver will drive a 10mhz differential signal onto cdp and cdn when a collision event is occurred. the cdp and cdn should be isolated by a pulse transformer. xrdp xrdm 84 85 i/tpi tpi receive input: 10base-t receive differential input pair. rxp and rxn should be shunted by a 100 ohms resistor for twisted-pair line impedance matching. tpdp tpdm 82 83 o/tpi tpi transmit output: 10base-t transmit differential output pair. a 1.21k ohm shunt resistor is required across the txp and txn for signal pre-equalization. act 73 o/led activity displaying: network activity displaying. act will indicate the network activity status by three types of signals(dc 0 , dc1 and ac 10hz). dc 0 : indicating "link good", if utp is selected. dc 1 : indicating 1) "link fail", if utp is selected. 2) "idle", if aui is selected. ac 10hz : indicating the dte is transmitting a packet or the carrier on the network is detected by the transceiver and the carrier sense signal is received by W89C940. the act will keep dc 1 if there is an abnormal network collision occurred, f.g. the transceiver collision signal always active. memory interface name number type description msd[7:0] 48 - 41 b/mos local memory data bus: a bidirection bus for data transfer between the local memory and the W89C940. msd0 is used as a serial data input pin during the auto configuration duration for hardware reset. the data drove by the do of eeprom will clocked into the msd0 when the eeprom load operation is active. the ethernet node id and optional configuration content will be loaded into chip s registers at this moment. msd1 is used as a serial data output pin during the auto configuration duration for hardware reset.the command drove by the msd1 will be clocked into the di of eeprom for accessing the content of eeprom. msd2 supplies the clock with a period of 1.2 s for eeprom during auto configuration duration.
W89C940 7 memory interface name number type description msrdb 49 o/mos local memory read enable. an active low signal to enable the local sram read. mswrb 50 o/mos local memory write enable. an active low signal to enable the local sram write. msa[14:0] 69 - 55 o/mos local memory address bus. address bus for local memory addressing. the msa14 will be used as the address strobe signal when the size is larger than 32kx8. if the rom size is larger than 32kx8, boot rom address !13-a10 is connected to msa13-msa10 and a17-a14 is connected to the latched msa13- msa10. the valid address for the higher significant bits(a14,a15,....) will be stable before the bpcsb is active low and should be latched by an external data latch which is triggered by msa14. the a0 ~ a13 of the boot rom device are connected to msa0 ~ msa13 directly no matter the boot rom size is larger than 32kx8 or not. rcsb 70 o/mos memory chip select: the rcsb is active low. rcsb enables the local memory read/write cycle in conjunction with the msrdb, mswrb pins. bpcsb 71 o/mos boot rom chip select: bpcsb is active low. bpcsb enables the boot rom read cycle during the system booting up. eecs 72 o/mos eeprom chip select. the eeprom read/write operation will be enabled when eecs is active high. power pins name number type description dvcc 1, 16, 30, 31, 54 i digital power supply: 5v dc power supply for internal digital logic circuitry. dgnd 15, 28, 32, 51, 86, 100 i digital ground: ground pins for internal digital logic circuitry. avcc 81 i analog power supply: 5v dc power supply for internal analog circuitry.
W89C940 8 power pins name number type description agnd 80 i analog ground: ground pin for internal analog circuitry. it is recommended that there is a decoupling capacitor connected between the power supply pins and ground pins. a rc low pass filter is also recommended to be used for analog power supply. note: signal type definition in input is a standard input-only signal out totem pole output is a standard active driver. t/s tri-state is a bi-directional, tri-state input/output pin. s/t/s sustained tri-state is an active low tri-state signal owned and driven by one and only one agent at a time. the agent that drives an s/t/s pin low must drive it high for at least one clock before letting it float. a new agent cannot start driving a s/t/s signal any sooner than one clock after the previous owner tri-states it. a pull-up is required to sustain the inactive state until another agent drives it, and must be provided by the central resource. o/d open drain allows multiple devices to share as a wire-or.
W89C940 9 functional description ieee 802.3 mac function core coprocessor (slct) operation the slct core coprocessor has five major logic blocks that control ethernet operations: the register files, transmit logic, receive logic, fifo logic, and dma logic. the relationship between these blocks is depicted in the following block diagram. register files the register files of the slct can be accessed in the same way as the configuration registers. the elanc-pci should be in slave mode when the system accesses the register files. the command register (cr) determines the page number of the register file, while the system address sa<0:3> selects one register address from 01h to 0fh. the pci io read/write commands are used to activate the i/o operations. refer to the w89c90 data sheet for more detailed information on the registers. dma interface logic the slct has two types of dma operations, local dma and remote dma. fifo logic the slct has a 16-byte fifo, which acts as an internal buffer to adjust transmission/reception speed differences between dmas. the fifo has fifo threshold pointers to determine the level at which it should initiate a local dma. the threshold levels are different for reception and transmission. the fifo threshold levels are defined in the dcr register. the fifo logic also provides a fifo overrun and underrun signal for network management purposes. in a case where the receive packets are flooding into the fifo but the slct still does not have the bus authority, the fifo may be overrun. on the other hand, if a transmission begins before data are fed into the fifo, it may be underrun. both cases result in a network error. these types of cases can be prevented by changing the values of the fifo thresholds. pci bus interface dma interface logic 16-byte fifo transmit logic receive logic sna tx/rx logic register files
W89C940 10 normally, the data in the fifo cannot be read; reading fifo data during normal operation may cause the system to hang. in loopback mode, however, the slct allows fifo data to be read by byte in order to check the correctness of the loopback operation. receive logic the receive logic is responsible for receiving the serial network data and packing the data in byte/word sequence. the receive logic thus has serial to parallel logic in addition to network detection capability. the elanc-pci accepts both physical addresses and group addresses (multicast and broadcast addresses). the slct extracts the address field from the serial input data. it then determines if the address is acceptable, according to the configurations defined in the receive configuration register (rcr). if the address is not acceptable, the packet reception is aborted. if the address is acceptable, the data packet is sent to the serial to parallel logic before being fed into the fifo. data packets can thus be processed either byte or word-wide. after receiving a data packet, the slct automatically adds four bytes of data receive status, next packet pointer, and two bytes of receive byte count into the fifo for network management purposes. the receive status contains the status of the incoming packet, so that the system can determine if the packet is desired. the next packet pointer points to the starting address of the next packet in the local receive ring. the receive byte count is the length of the packet received by the slct. note that the receive byte count may be different from the "length" field specified in the ethernet packet format. these four bytes of data will be transferred to the local buffer with the last batch of the local dma. however, these four bytes are stored at the first four addresses before the packet. transmit logic the slct must be filled before transmission begins. that is, the local dma read must begin before the slct begins transmission. the slct first transmits 62 bits of preamble, then two bits of sfd, and then the data packet. the parallel to serial logic serializes the data from the fifo into a data packet. after the data packet, the slct optionally adds four bytes of cyclic redundancy code (crc) to the tail of the packet. a protocol pla determines the network operations of the elanc-pci. collision detection, random backoff, and auto retransmit are implemented in the transmit logic. the protocol pla ensures that the elanc-pci follows ieee 802.3 protocol. 10base2 and 10base5 pls (physical layer signal) function sna operation tp or coax aui interface pll manchester encoder/decoder osc/ crytal slct interface logic l c e
W89C940 11 file 1 the elanc-pci also contains a serial network adapter (sna), which adapts the non-return-to-zero (nrz) used in the core processor and host system to manchester coded network symbols. the sna contains three blocks: a phase locked loop (pll), a manchester encoder/decoder, and a collision decoder, as well as crystal/oscillator logic. the manchester encoder/decoder handles code interpretation between nrz signals and manchester coded signals. the pll locks the receiving signals with an internal voltage control oscillator (vco) so that network noise(jitter) can be eliminated before the signals enter the core coprocessor. the collision decoder detects whether the network is in a collision status. 10base-t mau function tp transceiver operation transmit driver there are two signals for data transmission, txp and txn, which connect to the twisted-pair cable via a transmitter filter and an optional common mode choke. smart squelch the main function of this block is to determine when valid data are present on the differential receiving inputs (rxp/rxn). to ensure that impulse noise on the medium will not be taken as a valid datum, this circuit adopts a combination of amplitude and timing measurements to determine the validity of the input signals. to qualify incoming data, the smart squelch circuitry monitors the signals for three peaks of alternating polarity that occur within a 400 ns window. once this condition has been satisfied, the squelch level is reduced to minimize the noise effect and the chances of causing premature start of idle (soi) pulse detection. if the receiver detects activity on the receive line while packets are being transmitted, incoming data is qualified on five peaks of alternating polarity so as to prevent false collisions caused by impulse noise. the squelch function returns to its squelch state under any of the following conditions: ? a normal start of idle (soi) signal ? an inverted soi signal ? a missing soi signal a missing soi signal is assumed when no transitions have occurred on the receiver for 175ns after a packet has arrived. in this case, a normal soi signal is generated and appended to the data. collision detection a collision occurs when transmit and receive signals occur simultaneously on the twisted pair cable. collisions will not be reported when the device is in link-fail state. the collision signal is also generated when the transceiver has detected a jabber condition or when the sqe test is being performed. sqe test the signal quality error (sqe) test is used to test the collision signaling circuitry in the twisted pair transceiver module. after each packet transmission, an sqe signal is sent to the slct. the slct expects this signal and will flag an error if it does not exist. jabber the jabber timer monitors the transmitter and disables the transmission if the transmitter is active for greater than 26.2 ms.the jabber will re-enable the transmitter after the slct has been idle for at least 420 ms.
W89C940 12 link integrity during periods of inactivity, link pulses are generated and received by both maus at either end of the twisted pair to ensure that the cable has not been broken or shorted. a positive, 100 ns link integrity signal is generated by the twisted pair transceiver and transmitted on the twisted pair cable every 13 ms during periods of no transmission activity. the elanc-pci assumes a link-good state if it senses valid link pulse activity on the twisted pair transceiver receive circuit. if neither receive data nor a link pulse (positive or negative) is detected within 105 ms, the elanc-pci enters link-fail state. when a link-fail condition occurs, four consecutive positive link pulses (or eight negative link pulses) must be received before a link-good condition is assumed. lce core access function lce core access function (lce: lan controller of ethernet) the lce core of the elanc-pci can be accessed by programming the register of the lce core. the elanc- pci's register files are mapped into the lower 16 i/o spaces: iobase to iobase+0fh. any read/write to the elanc-pci's registers is an "in"/"out" command to these addresses. addresses iobase+10h to iobase+17h are mapped to the i/o port for the system to access the contents of the buffer memory. remote dma reads and writes correspond to "in"/"out" commands to these addresses. when addresses iobase+18h to +1fh are read a software reset will be issued to the core coprocessor and released about 780nsec later, automatically. the following table summarizes the i/o address mapping: address register operation iobase+00h - iobase+0fh lce core's registers slave register read/write iobase+10h - iobase+17h i/o ports remote dma read/write iobase+18h - iobase+1fh reset software reset the buffer memory map for lce core memory address space is summarized in the following table: ne2000 compatible 0000h - 001fh id registers 0020h - 00ffh 0100h - 3fffh unused 4000h - 7fffh 16k x 8 local memory 8000h - ffffh unused node id each node in an ethernet network has a unique six-byte id. the node id is mapped into the memory space of the elanc-pci. the elanc-pci will load the node id from the eeprom after power on reset. the node i.d. should be allocated in the first 3 words(with the address of 00h ~ 02h) of the eeprom.
W89C940 13 bus arbitration the elanc-pci handles bus arbitration automatically. the lan card can operate in four modes: idle state, slave read/write mode, dma mode, and pci mode. the elanc-pci controls the on-board devices by decoding these modes. at power on, the elanc-pci is in idle mode. if a register read/write command is issued, the elanc-pci enters the slave read/write mode. if a local dma or remote dma is initiated by the elanc-pci core coprocessor, the elanc-pci enters dma mode. a pci command will put the elanc-pci into pci mode. at any given time, the elanc-pci can be in only one state. the elanc-pci handles state changes automatically. however, two events, such as a dma command and an pci command, may be requested at the same time; in this case, the elanc-pci allocates the bus on a first-come, first-served basis. no predefined priority is set within the elanc-pci. ne2000 mode dma function the elanc-pci provides two dma channels for system access. the remote dma mode moves data between system memory space and local memory space. the local dma moves data between the fifo of the slct and local memory space. however, since the slct can handle local dma operations without system intervention (refer to the data sheet for the slct), the system has to perform only remote dma reads/writes. in a transmit operation, the data should be moved to local memory before the system orders the slct to start transmission. the remote dma write moves the data from the pci bus to the local sram. this is simply an "out" command on the pc. for a receive operation, the network may feed data constantly and the local memory may become full if the data are not moved out to system memory through a remote dma read operation. this operation is the "in" command on the pc. remote dma a remote dma can be performed only in i/o mode. the remote dma moves data between the host and the local buffers. unlike a local dma, the remote dma is byte or word-wide. each remote dma operation transfers four bytes, double-word, depending on the pci cycle. since the remote dma is simply an pci i/o operation, pci is sometimes affected by a remote dma. if the remote dma is interleaved with other devices, trdy# is deasserted to force the system to insert wait states. the elanc-pci will automatically handle any arbitration necessary. a double word access on W89C940 from pci bus is allowed. the buffer memory access will stop when the remote byte counter is decreased to zero. a double word read command will read only three bytes of valid data if remote byte counter is set 3 or two bytes of valid data if the remote byte counter is set 2 respectively. local dma the local dma transfers data from/to the on-board buffers. to perform data reception or transmission from/to remote nodes in the network, data must be moved from/to the fifo. to enhance the efficiency of the transmission, the local dma transfers data in batches: data are first collected and then moved in a batch. each transfer can move up to 12 bytes of data at once. this scheme reduces time wasted in requesting the bus. a local dma begins by requesting the local bus. if the bus is available to the elanc-pci, it responds at once by asserting the bus acknowledge; if, on the other hand, the bus is currently authorized to another device, the elanc-pci will not assert the bus acknowledge and the slct must wait. note that this sequence will not affect the host system or the pci bus signals. after each batch is transferred, the slct checks the fifo threshold levels to determine if another batch transfer should be requested.
W89C940 14 boot prom access function boot prom operation for diskless applications, the system requires an on-board boot device. the elanc-pci allows the system to use an on-board boot prom as the boot device. the boot prom is essentially a byte-read device. elanc-pci will fetch a byte from the boot prom and drive the ad bus of the pci interface. if the system do a word read command, the elanc-pci will invoke two byte read operation with consecutive address and drove the second byte on another byte of the pci interface. for double word command, the elanc-pci will deassert the trdy# until four read operation with consecutive address to the boot prom is completed and then the four bytes of data will be drove onto the 32 bits data bus of pci. W89C940 can support the eprom and flash memory with 220nsec access time with the size up to 256kb. in order to support 64kb,128kb and 256kb size with 15-bit address bus, W89C940 use msa14 to latch the high address bits msa[17:14] from msa[13:10]. the structure for address latch is shown as following. W89C940 74ls373 eprom msa14/l msa[9:0] msa[13:10] msa[17:14]
W89C940 15 configuration programming function elanc-pci mode configuration registers mcr a mode configuration register(mcr) is used to program the operation mode of the elanc-pci. the address is page 0, 0ah. mcr can be updated by software. reading this register is the same as reading a register in the slct core coprocessor. writing to these registers is done by first reading the register to be written to and then using a slave write operation to update the configurations. the content of mcr is as following table: bit symbol description 0 1 phy0 phy1 physical layer interface: these two bits select the type of physical interface which the elanc-pci attached on. both the thin ehternet and thick ethernet type use the aui of elanc-pci as the input/output interface. the other two utp types,then, use the tpi of elanc-pci as the input/output interface. the output and input pins of aui or tpi are idle, when the corresponding type is not selected. phy1 phy0 physical interface type 0 0 utp (with 10base-t compatible receive squelch level) 0 1 thin ethernet 1 0 thick ethernet (aui port) 1 1 utp (with reduced receive squelch level) 2 gdlnk good link status: a read operation on this bit will get the link test status. a "1" indicate that it is link good and a "0" is link fail. the gdlnk do not imply any information if the phy0 and phy1 is programmed as thin or thick ethernet. 3 lnken link test pulse enable: the network media auto switching function, link integrity test function and the link test pulse generation function will be enabled when lnken = "0". otherwise, all of these functions will be disabled when lnken = "1". 4 shls sram high/low speed select: high speed sram with 20nsec access time is selected if shls =1. low speed sram with 70nsec access time is selected if shls =0. 5 6 7 bps0 bps1 bps2 boot prom size: the size of the boot prom is selected by bps0, bps1, and bps2. bps2 bps1 bps0 size 0 0 x no boot prom 0 1 0 8k 0 1 1 16k 1 0 0 32k 1 0 1 64k 1 1 0 128k 1 1 1 256k
W89C940 16 pci bus operation configuration registers the W89C940 implement a system configuration registers for pci bus auto configuration function. the W89C940 support the predefined header portion of the system configuration space ( i.e. first 64 bytes of the 256 bytes configuration space). a summarized table for those registers is as following. address of configuration space register attribute default value after power on write by 01h~00h vendor-id r/w 1050h eeprom 03h~02h device-id r/w 5a5ah eeprom 05h~04h command r/w 0000h s ystem s/w 07h~06h status r/w 0280h s ystem s/w 08h revision-id r/w 00h eeprom 0bh~09h class-code r 020000h none 0ch cache-line-size r 00h none 0dh latency-timer r 00h none 0eh header-type r 00h none 0fh bist r 00h none 13h~10h i/o-base-address r/w ffffffe1h s ystem s/w 17h~14h reserved-reg.-0 r 00000000h none 1bh~18h reserved-reg.-1 r 00000000h none 1fh~1ch reserved-reg.-2 r 00000000h none 23h~20h reserved-reg.-3 r 00000000h none 27h~24h reserved-reg.-4 r 00000000h none 2bh~28h reserved-reg.-5 r 00000000h none 2fh~2ch reserved-reg.-6 r 00000000h none 33h~30h rom-base-address r/w ffff8001h s ystem s/w 37h~34h reserved-reg.-7 r 00000000h none 3bh~38h reserved-reg.-8 r 00000000h none 3ch interrupt line r/w 00h system s/w 3dh interrupt pin r 01h none 3eh min-gnt r/w 00h eeprom 3fh max-lat r/w 00h eeprom the vendor id, device id, revision id, min-gnt and max-lat are programmed by eeprom, i.e. the contents of these register can be updated by eeprom load only. the i/o base address and the rom base address registers can be updated by system software. those system configuration registers should be accessed by a double word access operation. the W89C940 will drive 32 bits data on the bus when these configuration registers are accessed. vendor id register the vendor i.d. identifies the manufacturer of the device. valid vendor identifiers are allocated by the pci sig to ensure uniqueness. the content of this register will be updated after power on by the eeprom load operation. the vendor id should be programmed into the word with 09h address of the eeprom for power on auto loading.
W89C940 17 device i.d. register the device i.d. identifies the particular device. this identifier is allocated by the vendor.the content of this register will be updated after power on by the eeprom load operation. the device id should be programmed into the word with 0ah address of the eeprom for power on auto loading. command register bit location attribute description 0 r/w this bit controls the i/o space access response of W89C940. a value of "0" will disables the W89C940 response. a value of "1" allows the W89C940 to respond to i/o space accesses. 1 r/w this bit controls the memory space access response of W89C940. a value of "0" will disables the W89C940 response. a value of "1" allows the W89C940 to respond to memory space accesses. 2 r the W89C940 do not support pci bus master function. this bit is fixed to "0". 3 r the W89C940 do not support the special cycle operation. this bit is fixed to "0" 4 r the W89C940 do not support the memory write cycle and the invalidate command. this bit is fixed to "0". 5 r the W89C940 is not a vga compatible device. this bit is fixed to "0". 6 r/w this bit controls the parity error response of W89C940. a value of "0" will force the W89C940 ignore a parity error. a value of "1" allows the W89C940 to take a normal action when a parity error is detected. this bit will be reset after power on. 7 r the W89C940 do not support data stepping function and this bit is fixed to "0" always. 8 - this bit is an enable bit for W89C940 internal serr# driver. a value of "0" will disables the internal serr# driver. a value of "1" enables the internal serr# driver. 9~15 r all of these bits are fixed to "0" internally. and no specific function are related to these bits.
W89C940 18 status register bit location attribute description 15 r/w this bit will be set "1" by W89C940 when it detects a parity error, even if parity error handling is disabled(as controlled by bit 6 in the command register). a "write 1" operation on this bit will clear this bit. this bit will be set "0" after it is cleared. 14 r/w this bit will be set "1" by W89C940 when it assert the internal serr#. a "write 1" operation on this bit will clear this bit. this bit will be set "0" after it is cleared. this bit is read only for 100 pin package and is fixed to "0". 13 r the W89C940 do not support pci bus master function. this bit is fixed to "0". 12 r the W89C940 do not support pci bus master function. this bit is fixed to "0". 11 r/w this bit will be set "1" by W89C940 when it terminates a transaction with target-abort. a "write 1" operation on this bit will clear this bit. this bit will be set "0" after it is cleared. 10~9 r the bit-10 is fixed to "0" and bit-9 is fixed to "1". it indicated that the W89C940 assert the devsel# with medium speed. 8 r the W89C940 do not support pci bus master function. this bit is fixed to "0". 7 r the W89C940 support fast back-to-back transaction. 6~0 r all of these bits are fixed to "0" internally. and no specific function are related to these bits. there are two cases that the W89C940 will initiate the target-abort. the first one is the addressing parity check error cause internal serr# asserted but without stop# signal and the second one is the byte enable and address check error that the stop# is asserted. if addressing don't match the following table, the target doesn't transfer the data, but terminate with target abort. ad1 ad0 c/be3# c/be2# c/be1# c/be0# 00xxx0 01xx01 10x011 110111 revision i.d. register the revision i.d. is chosen by the vendor. it specifies a device specific revision identifier. zero is an acceptable value. it can be viewed as a vendor defined extension to the device i.d. the content of this register will be updated after power on by the eeprom load operation. the revision id should be programmed into the 23th byte of the eeprom for power on auto loading.
W89C940 19 class code register the class code register is read only. the code of 020000h indicates that the W89C940 is a ethernet controller. cache-line-size register the W89C940 do not support the memory write and invalidate command. all bits of this register are fixed to "0". latency-timer register the W89C940 do not implement a writable latency timer. all bits of this register are fixed to "0". header-type register the W89C940 is a single function device. the bit 7 of header type register is fixed to "0" and all of other bits of this register are also fixed to "0". bist register the W89C940 do not support the built in self test function. it will always return "00h" for a reading operation. i/o-base-address register bit 31~24 23~16 15~8 7 6 5 4 3 2 1 0 attribute r/w r/w r/w r/w r/w r/w r r r r r initial value ffh ffh ffh 1 1 1 0 0 0 0 1 the bit 0 fixed to "1" indicates that W89C940 requires the i/o space of the system as its buffer for data transfer. the bit 0 to bit 4 implemented as a read only field imply that W89C940 need a i/o space with a range of 32 bytes. the power-up software can determine how munch address space the device required by writing a value of all 1's to the register and then reading the value back. the W89C940 will return 0's in all don't care address bits(bit 0 ~ bit 4), effectively specifying the address required, if the idsel and the configuration command are recognized. the i/o base address will be decided by the bit 5 to bit 31 of the i/o base address register. the system software should write the base address(32 bits address) onto this register. the bit 0 to bit 4 will be ignored by W89C940. the bit 5 to bit 31 will be used as a reference value of the address decoder of the W89C940. there are nine types of command decoded by c/be[0:3]# during the address phase of a transaction. these nine types of command are as the following table. c/be[3:0]# command type 0010 i/o read 0011 i/o write 0110 memory read 0111 memory write 1010 configuration read 1011 configuration write 1100 memory read multiple, this command will be decoded as the memory read command 1110 memory read line, this command will be decoded as the memory read command 1111 memory write and invalidate, this command will be decoded as the memory write command the last three commands are used in cache memory access. the application of W89C940 do not support this command.
W89C940 20 rom-base-address register bit 31~24 23~16 15~8 7~0 attribute r/w r/w r/w r/w initial value ffh ffh 80h 01h the W89C940 supports 8kx8, 16kx8, 32kx8, 64kx8, 128kx8 and 256kx8 rom address decoding function. for a 8kx8 rom application, the upper 19 bits of this register correspond to the upper 19 bits of the expansion rom base address. the lower 13 bits of this register correspond to the size of the expansion rom. those bits correspond to the size of the expansion rom are determined by mcr bit 5, bit 6 and bit 7 and can not be writable by the system configuration write command. the device independent configuration software can only determined the bits corresponding to the base address. the following table describe the relationship between the addressing bus, sizing bits and the mcr bit 5/6/7. mcr.7 mcr.6 mcr.5 addressing bits sizing bits rom size 0 0 x none none no boot rom 0 1 0 31~13 12~0 8kx8 0 1 1 31~14 13~0 16kx8 1 0 0 31~15 14~0 32kx8 1 0 1 31~16 15~0 64kx8 1 1 0 31~17 16~0 128kx8 1 1 1 31~18 17~0 256kx8 the device independent configuration software can only determined the addressing bits. the bit 0 of the rom base address register will be reset "0" by W89C940 if the mcr is set as "no boot rom", i.e. bps0=0, bps1=0 and bps2=0. the bit 0 of the rom base address register will be set "1" if the mcr is programmed as there is an expansion rom device add-on the lan adapter. the initial value of ffff8001h indicates that there is a 32kx8 expansion rom device existing. the initial value is changed according to the boot rom size selection in the mcr (mode configuration register). interrupt line register this register is a readable and writable register. the post software of system could write the routing information into this register as it initializes and configures the system. the value in this register tells which input of the system interrupt controllers the device's interrupt pin i connected to. device drivers and operating systems can use this information to determine priority and vector information. for x86 based pcs, the value in this register correspond to irq numbers (0-15) of the standard dual 8259 configuration. the value 255 is defined as meaning "unknown" or "no connection" to the interrupt controller. values between 15 and 255 are reserved. interrupt pin register the W89C940 use the inta# as its interrupt pin. the content of this register is fixed into "01". min-gnt register it is used for specifying how long a burst period the device needs assuming a clock rate of 33mhz. the content of this register will be updated after power on by the eeprom load operation. the min-gnt should be programmed into the 17th byte of the eeprom for power on auto loading.
W89C940 21 max-lat register it is used for specifying how often the device needs to gain access to the pci bus. max_lat is used to set the devices desired settings for latency timer values. the registers specify the values in units of 0.25 microsecond. zero means the device has no major requirements for the settings of latency timer. the content of this register will be updated after power on by the eeprom load operation. the max-lat should be programmed into the 18th byte of the eeprom for power on auto loading. eeprom programming function eeprom load and reload procedure a eeprom control register(ecr) is used to control the operation mode of the eeprom. the ecr is allocated on the register address of page 3, 02h of lce. the content of ecr is as following table: bit symbol description 0-5 reserved 6 erws eeprom read write select: the write sequence to eeprom is selected if erws = 1. if erws = 0, the read sequence is selected. 7 eac eeprom access control: eac will enable the eeprom read/write sequence if eac = 1. the eas will be reset to " 0 " if the read/write sequence finished. set eac = 0 will abort the eeprom read/write sequence immediately. the read/write sequence for eeprom is described as following two statements. write sequence: write(ecr with erws=1 and eac=1); /* enable the write sequence */ write(bfr, address); /* specify the address in which the data will be modified */ write(bfr, word_data); /* specify the data which will be write into the eeprom */ repeat( read(ecr.eac); ) until (eac=0); /* wait for the programming process completed */ file2 any operation that violate the write sequence will cause the eeprom programming process aborted. the bfr is a buffer register located at the register address of page3, 04h of lce. with the eeprom load back sequence specified above, the contents at the specified address will be overwritten by the new data. one word of data is modified by each write sequence. the allowable address in which the content will be modified is from 00h to 3fh. read sequence: write(ecr with erws=0 and eac=1); /* enable the read sequence */ write(bfr, address); /* specify the address in which the data will be read out */ repeat( read(ecr.eac); ) until (eac=0); /* wait for the reading process completed */ read(bfr); /* read word data */
W89C940 22 the read data will be kept in the bfr after the reading process is completed. the content of bfr will not changed except that the other write or read sequence is started or a write(bfr, address) operation is executed. i.e. the data of bfr can be read out any time afterwards. eeprom content the format of eeprom contents is as followings: address high byte low byte bit 15 ~ bit 8 bit 7 ~ bit 0 0fh reserved reserved 0eh reserved reserved 0dh reserved reserved 0ch reserved reserved 0bh mcr revision i.d. 0ah device i.d.(high byte) device i.d.(low byte) 09h vendor i.d.(high byte) vendor i.d.(low byte) 08h max_lat min_gnt 07h 57h 57h 06h reserved reserved 05h reserved reserved 04h reserved reserved 03h reserved reserved 02h ethernet address 5 ethernet address 4 01h ethernet address 3 ethernet address 2 00h ethernet address 1 ethernet address 0 the 5757h located at 07h address is used for ne2000 compatibility. the elanc-pci will load this parameter into its internal register file for ne2000 software compatibility. eeprom load timing a system reset should allow at least 1usec for the W89C940 to decode the action as a reset. after reset signal, the device start to read the eeprom after 1usec. the read clock is sent by the W89C940 to the eeprom. normally the period of the clock is 1.2usec. it will take about 14.4usec to read the 12 bytes of data from eeprom. the reset timing is as shown below.
W89C940 23 since the elanc-pci reloads data into the configuration registers each time the system is reset, caution should be taken in handling resets. a system reset should keep low at least 480ns for the elanc-pci to decode the action as a reset. any signal on the reset pin shorter than this will be interpreted as noise and no response will be taken by the elanc-pci. after the reset signal is recognized, the elanc-pci to read configurations and id contents from the eeprom. the read clock is sent by the elanc-pci to the eeprom. normally the period of the clock is 1.2 s. the elanc-pci will serially generate the eeprom address so that the configuration and id after the reset signal is recognized, the elanc-pci to read configurations and id contents from the eeprom. the read clock is sent by the elanc-pci to the eeprom. normally the period of the clock is 1.2 s. the elanc-pci will serially generate the eeprom address so that the configuration and id will be read into the internal register file of W89C940. network status led display function network segment status led display network activity displaying. act will indicate the network activity status by three types of signals (dc0 dc1 and ac 10hz). dc 0 : indicating "link good", if utp is selected. dc 1 : indicating 1) "link fail", if utp is selected. 2) "idle", if aui is selected. ac 10hz : indicating the dte is transmitting a packet or the carrier on the network is detected by the transceiver and the carrier sense signal is received by W89C940. the act will keep dc 1 if there is an abnormal network collision occurred, e.g. the transceiver collision signal always active. utp or coaxial auto-selection function auto media-switching the elanc-pci provides a utp/bnc auto media-switching function. the physical interface will jump from utp to bnc when the elanc-pci is configured as utp, link checking is enabled, and the current utp path is broken. it will jump back immediately after the utp path has been reconnected. when the physical interface is configured as bnc or aui, this auto media-switching function will be disabled. a t l eas t eeread rst# 1usec 1usec 14.4usec
W89C940 24 phy1 phy0 lnken gdlnk auto switching function 0 0 1 1 disabled, keep at utp 0 0 0 1 enabled, keep at utp 0000 enabled, utp switch to bnc or aui 0111 disabled, keep at aui 0 1 0 0 or 1 disabled, keep at aui 1011 disabled, keep at aui 1 0 0 0 or 1 disabled, keep at aui 1111 disabled, keep at utp 1101 enabled, keep at utp 1100 enabled, utp switch to bnc or aui signature register the signature register can be read by pci configuration cycle with address 40h. the consecutive read will get a data pattern 88h, 00h, 88h, 00h,.... if byte enable (c_beb#) is asserted. a write operation will have no effect on the content of this signature register. early interrupt function 1. background: W89C940 includes some control circuit and status register bits to generate interrupt signal early during receiving packets. besides traditional interrupt generated at incoming packet end, W89C940 can generate interrupt when received packet bytes reach early interrupt threshold and early interrupt function is enabled. 2. register list: registers io address descriptions eir_en page 0 base+0bh [0] early interrupt enable register: read/write asserted high to enable early interrupt function. deasserted to disable early interrupt function. to program receive control register (rcr) to monitor mode or data configuration register (dcr) to loopback mode will also disable early interrupt function. initial value after power-on reset is 0. read once write. eir_mask page 0 base+0bh [1] early interrupt mask register: read/write asserted high to initiate an interrupt on inta# of pci local bus when an early interrupt event occured. deasserted this register will mask an interrupt generated. deasserted this register does not disable early interrupt status register. initial value after power-on reset is 0.read once write. eir_statu s page 0 base+0bh [7] early interrupt status register: read/write asserted high when the byte count of incoming frame reaches early interrupt threshold with correct destination address (ds), in the enable mode of early interrupt function. write 1 to clear eir_status. initial value after power-on reset is 0. read once write.
W89C940 25 eir_thd [15:0] page 3 base+06h [15:0] early interrupt threshold register: word read/write early interrupt threshold is in the unit of byte. the minimum value of threshold is 64 bytes. any value less than 64 bytes will be treated as 64 bytes except value 0000h. not to program threshold or program 0000h will be disable early interrupt function. the initial threshold value after power-on reset is 0000h. clda0[7:0] clda1[7:0] page 0 base+01h[7:0] base+02h[7:0] current local dma address register: read only. currrent address of local dma. use word io read command to access the content. initial value after power-on reset is 0000h. using word command to read port base+01h will have both clda0 & clda1. 3. program procedure: a. set eir_en=1 to enable eraly interrupt function and set eir_mask=1 to enable interrupt pin inta# of pci local bus. b. program eraly interrupt threshold, eir_thd. c. set dcr not in loopback mode. d. set rcr not in monitor mode. e. program cr to start receive packet. f. wait until a frame with a correct destination address and receive byte count greater than early interrupt threshold. g. an intrrupt initiated and eir_status register set. ps: a, b, c, d & e can also be programmed individually. pci bus transaction this section will introduce the read transaction, write transaction, and termination transaction of pci bus. read transaction ( i/o and memory read ) the timing of read transaction is shown in figure.
W89C940 26 clk 1 2 3 4 5 6 7 8 ad[31::0] address bus cmd data be#'s par stop# devsel# trdy# irdy# c_be[3:0]# frame# the transaction is initiated by frame# , the address is asserted and bus read command of c/be[3:0]# is also asserted. this phase is called address phase. irdy# (initiator ready) is asserted by master after address phase. target initiate trdy#( target ready) and assert valid data on the bus. the devsel# means the target is addressed and respond to the master device. the data transaction is happened on both irdy# and trdy# are asserted on the same clock edge that is called data phase. during the data phase, the be (byte enable) indicate the data length of the data. if it is a double word, 32 bits, the be will be 0000. if data is a word, the be will be 1100 or 0011 if the host send the memory read command in burst mode, W89C940 accept the first data phase access and then reject the further data access request with retry disconnection. only one data phase is allowed for transaction. write transaction ( i/o and memory write) the write transaction is like read transaction, the frame# initiate the transaction with address phase and the data is written in data phase. the data could be asserted directly after address phase. it does not need a wait state for avoiding bus contention. the transaction is ended when the frame#, irdy#, trdy# and devsel# are deasserted. if the host send the memory read command in burst mode, W89C940 accept the first data phase access and then reject the further data access request with retry disconnection. only one data phase is allowed for transaction. the write transaction is as shown in the figure
W89C940 27 clk ad[31::0] address bus cmd data be#'s 1 2 3 4 5 6 7 8 frame# c_be[3:0]# irdy# trdy# devsel# stop# par configuration read transaction the configuration read timing is as shown clk ad[31::0] address bus cmd data be#'s 1234567 idsel 8 frame# c_be[3:0]# irdy# trdy# devsel# stop# par the timing is the same as the figure i/o read transaction, except the idsel is asserted during the address phase. the transaction access the configuration registers of the device. configuration write transaction the timing is as shown.
W89C940 28 clk ad[31::0] address bus cmd data be#'s 1 2 3 4 5 6 7 8 frame# c_be[3:0]# irdy# trdy# devsel# stop# par idsel the timing is the same as the figure i/o read transaction, except the idsel is asserted during the address phase. the transaction access the configuration registers of the device. transaction termination target initiated termination the W89C940 device can only work in slave mode. it respond to the request from the master device and act as a target. sometimes the target are unable to answer the master device and initiate a termination. there are two types of termination will occur. the first one is disconnect-c/retry type. the second one is target abort type. the timing is as shown in the figure the first type is the disconnect-c/retry type, as shown in the figure
W89C940 29 clk frame# ad[31::0] irdy# trdy# address bus cmd be#'s 1 2 3 4 15 16 17 c/be[3::0]# 0 18 19 stop# devsel# because W89C940 don't support memory command in burst mode. when the host try to send memory command in burst mode, the first data phase is completed. trdy# and irdy# are deasserted, but the frame# is asserted for the next data phase. the device will assert stop# to terminate the transaction. data is not transferred after stop# is asserted. the host need to initiate another transaction for further data transfer. the timing is shown above. the target-abort type, as shown in the figure clk frame# ad[31::0] irdy# trdy# address bus cmd be#'s 1 2 3 4 5 6 7 c/be[3::0]# 0 stop# devsel# 8 9 the condition is the target requires the transaction to be terminated and does not want the transaction tried again. as shown in the figure, the devsel# is deasserted when stop# is asserted. if there is a data needed to be transferred, devsel# must be asserted for one or more clock cycles and trdy# must be deasserted before target-abort can be signaled. there are two cases that the device will initiate the target-abort. the first one is the addressing parity check error cause internal serr# asserted and the second one is the byte enable and addressing check error. if addressing don't match the following table, the target doesn't transfer the data, but terminate with target abort. ad1 ad0 c/be3# c/be2# c/be1# c/be0# 0 0xxx0 01xx01 10x011
W89C940 30 110111
W89C940 31 fast back-to-back transactions clk frame# ad[31::0] irdy# trdy# devsel# stop# address bus cmd data be#'s 1 2 3 4 5 6 7 par c/be[3::0]# 8 address bus cmd be#'s data without contention of trdy#, devsel#, or stop#, the idle states between transactions are removed. it increase the throughput of the data transaction. if the first transaction is a write cycle and the second transaction access( can be read or write transaction) to the same target , one idle cycle can be removed between transactions. parity as shown in the figure below, parity is generated at immediately following clock and the internal perr# is after par. parity is calculated the same on all pci transactions regardless of the type or form. parity covers ad[31:0] and c/beb[3:0]# lines regardless of whether or not all lines carry meaningful information. the number of 1s on ad[31:0], c/beb[3:0]# and par equals an even number. parity is also calculated at configuration phase. clk frame# ad[31::0] address bus cmd data be#'s 1 2 3 4 5 par perr# c_be#[3::0]
W89C940 32 test mode setting and definition W89C940 provide three test modes they are 90 test mode, tp test mode, and aui test mode. the system reset signal is fed into 400ns low glitch eater and the output is rst_i. at 400 nsec rst_i asserted period, the three pins (eecs,bpcsb,rcsb) output (0,1,1). after rst_i deasserted, the three pins become input pins and sample at 90nsec. the sampled value (*1,*2,*3) determine the test mode. the timing and test mode type is shown as following. 400ns low glitch eater 400ns low glitch eater pci rstb rst_i rst_i eecs_o 0 z z z 0 bpcs_o 1 z z z 1 rcsb_o 1 z z z 1 eecs_i z z *1 z z bpcsb_i z z *2 z z rcsb_i z z *3 z z eecs_o: eecs pin output driver eecs_i : eecs pin input forcing (*1, *2, *3) = (0,1,1) ---- normal operation mode = (1,0,0) ---- fast eeprom mode = (1,0,1) ---- 90 test mode = (1,1,0) ---- tp test mode = (1,1,1) ---- aui test mode = (0,0,0) ---- aui linear mode file 3
W89C940 33 absolute maximum ratings symbol parameter minimum maximum unit ta operating temperature 0 70 c ts storage temperature -55 150 c v dd supply voltage -0.5 7.0 v v in input voltage v ss -0.5 v dd +0.5 v v out output voltage v ss -0.5 v dd +0.5 v tl lead temperature (soldering 10 seconds maximum) 250 c power supply (v dd =4.75 v to 5.25v, v ss =0 v, ta=0 c to 70 c) symbol parameter condition minimum maximum unit iddi power supply current(idle, clock active) vdd=5.25v 150 ma iddt power supply current(transmitting) vdd=5.25v 250 ma dc characteristics (v dd =4.75 v to 5.25 v, v ss =0 v, ta=0 c to 70 c) digital: symbol parameter condition minimum maximum unit v il low level input voltage v ss -0.5 0.8 v v ih high level input voltage 2.0 v dd +0.5 v v ol low output voltage iol=4.0ma 0.4 v v oh high output voltage ioh=-4.0ma 2.4 v i il1 input leakage current (note 1) vin=5.25v vin=0v 10 a i il2 input leakage current (note 2) vin=5.25v vin=0v 2 ma
W89C940 34 i ol tristate leakage current vout=vdd vout=vss -10 0.3 ma a note 1: all of the input pins except those stated in note 2.; note 2: xrdp, xrdm, cdp, cdn, rxp, rxn. aui: symbol parameter condition minimum maximum unit v dd differential output voltage (txp/n) as the test load +/-550 +/-1200 mv v ob differential idle output voltage imbalance (txp/n) as the test load +/-40 mv v u undershoot voltage (txp/n) as the test load 100 mv v ds differential squelch threshold (cdp/n, rxp/n) -175 -300 mv v cm differential input common mode voltage (cdp/n, rxp/n) 2.0 4.0 v twisted pair: symbol parameter condition minimum maximum unit r ti xrdp/m differential input resistance 3 kohms v tib xrdp/m open circuit input voltage (bias) -2.75 vdd-1.0 v v tiv xrdp/m differential input voltage range vdd=5v -3.1 3.1 v v tps xrdp/m positive squelch threshold 300 585 mv v tns xrdp/m negative squelch threshold -585 -300 mv v tpu xrdp/m positive unsquelch threshold 200 350 mv v tnu xrdp/m negative unsquelch threshold -350 -200 mv v toh tpdp/m high output voltage i=32ma vddtp-.44 vddtp v
W89C940 35 v tol tpdp/m low output voltage i=32ma vsstp vsstp+.44 v i to tpdp/m output current 32 ma r to tpdp/m output resistance 13.5 kohms
W89C940 36 preliminary switching characteristics pci accesses read transaction clk ad[31::0] address data be#'s 1 2 3 bus cmd devsel# trdy# irdy# c/be[3:0]# frame# t9 t11 t12 t13 t10 par t7 input output t2 t3 t5 t8 t1 t4 t6 t14 t15 idsel# 0 symbol description min typical max unit t1 pci input signal set up time* 7 nsec t2 pci input signal hold time* 0 nsec t3 be byte enable set up time 7 nsec t4 be byte enable hold time 0 nsec t5 irdy# set up time 7 nsec t6 irdy# hold time 0 nsec t7 par input setup time 7 nsec t8 par input hold time 0 nsec t9 devsel# driven time 11 12 13 nsec t10 devsel# hold time 11 12 13 nsec t11 output data hold time 18 19 20 nsec t12 trdy# driven time 11 12 13 nsec t13 trdy# hold time 11 12 13 nsec t14 par output driven time 11 12 13 nsec t15 par output hold time 11 12 13 nsec *address, command, and frame# for slave access, idsel# for configuration read transaction
W89C940 37 write transaction clk ad[31::0] address data be#'s 1 2 3 bus cmd devsel# trdy# irdy# c/be[3:0]# frame# t9 t11 t12 t13 t14 t10 par t7 input input t1 t2 t3 t5 t8 t15 t4 t6 t16 idsel# perr# t17 t18 0 data symbol description min typical max unit t1 pci input signal setup time* 7 nsec t2 pci input signal hold time* 0 nsec t3 be byte enable set up time 7 nsec t4 be byte enable hold time 0 nsec t5 irdy# set up time 7 nsec t6 irdy# hold time 0 nsec t7 par input setup time 7 nsec t8 par input hold time 0 nsec t9 devsel# driven time 11 12 13 nsec t10 devsel# hold time 11 12 13 nsec t11 input data set up time 7 nsec t12 input data hold time 0 nsec t13 trdy# driven time 11 12 13 nsec t14 trdy# hold time 11 12 13 nsec t15 par input setup time 7 nsec t16 par input hold time 0 nsec t17 internal perr# driven time** 11 12 13 nsec t18 internal perr# hold time** 11 12 13 nsec *address, command, and frame# for slave access, idsel# for configuration read transaction **internal perr# will be asserted if the parity error event occurred.
W89C940 38 transaction termination disconnect-c/retry type clk frame# ad[31::0] irdy# trdy# address bus cmd be#'s 1 2 3 4 15 16 17 c/be[3::0]# 0 t1 18 19 t3 stop# devsel# t2 symbol description min typ max unit t1 frame# deasserted from clock 15 0 nsec t2 clock 16 to stop# asserted time 11 12 13 nsec t3 clock 18 to stop# and devsel# hold time 11 12 13 nsec note: 1) the other timing requirements for pci input signal are as the read transaction timing. 2) t1,t2 and t3 are used for the disconnect type c(host try to transfer more than one data phase). target-abort type clk frame# ad[31::0] irdy# trdy# address bus cmd be#'s 1 2 3 4 5 6 7 c/be[3::0]# 0 t1 t2 stop# t3 devsel# 8 9 symbol description min typ max unit t1 frame# deasserted from clock 15 0 nsec t2 clock 4 to devsel# hold time 11 12 13 nsec t3 clock 6 to stop# hold time 11 12 13 nsec note: 1) the other timing requirements for pci input signal are as the read transaction timing.. 2) t2 and t3 are used for the target abort type(host addressing error). fast back-to-back transactions
W89C940 39 clk ad[31::0] devsel# trdy# irdy# c/be[3:0]# frame# par bus cmd be#'s address data address write data be#'s 1 2 3 4 5 6 78 bus cmd input input 0 t1 symbol description min typical max unit t1 frame# set up time to clock 6 7 nsec
W89C940 40 memory support bus access 32kx8-20 sram remote read byte access cycle clk 1 2 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] data devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t2 t1 t4 t3 t5 n+4 n+7 n+8 n+ 9 t6 t7 n+5 n+6 symbol description min typical max unit
W89C940 41 t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec remote read word access cycle clk 1 2 3 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t2 t1 t4 n+ 4 n+5 n+ 6 data t8 t3 t5 n+9 n+10 n+11 t6 t7 t7 t6 n+8 note: 1) the other timing requirements for pci signal are as the read transaction timing. 2) n=0,1,2,3,..... when local dma get the control of the bus, pci bus will insert wait state. wait state number is n. symbol description min typical max unit t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec
W89C940 42 t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec t8 msd hold time from clock n+8 nsec remote read double word access cycle clk 1 23 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] data devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t1 t4 t3 n+ 4 n+5 n+ 6 n+7 t2 t8 n+8 n+9 t5 t6 t7 t7 t6 t6 t7 t7 t6 t2 t8 n+10 n+11 n+12 n+13 n+14 symbol description min typical max unit t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec t8 msd hold time from clock n+8 nsec remote write byte access cycle
W89C940 43 clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 msa0-13 t1 msrdb rcsb msd0-7 mswrb t4 t3 t5 t6 0 n+ 5 n+ 6 n+ 7 n+8 n+9 t7 symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+5 to msd valid 7 12 17 nsec t6 clock n+7 to msd deasserted 14 19 24 nsec t7 msa change to mswrb deasserted time 17 22 27 nsec t8 clock n+7/ n+9 to msd deasserted 16 21 26 nsec t9 clock n+9 to msd deasserted 8 13 18 nsec file4 remote write word access cycle
W89C940 44 clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 t5 msa0-13 t1 msrdb rcsb msd0-7 mswrb t4 t3 t7 t6 t8 0 n+ 5 n+ 6 n+ 7 n+8 n+9 n+10 n+ 11 t9 t4 t3 t10 t11 note: 1) the other timing requirements for pci signal are as the read transaction timing. 2) n=0,1,2,3,..... when local dma get the control of the bus, pci bus will insert wait state. wait state number is n. symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+10 to rcsb deasserted 7 12 17 nsec t6 clock n+9 to msa deasserted 14 19 24 nsec t7 clock n+5 to msd valid 17 22 27 nsec t8 clock n+7 to msd deasserted 16 21 26 nsec t9 clock n+10 to msd deasserted 8 13 18 nsec t10 msa change to mswrb deasserted time t11 msa change to mswrb deasserted time
W89C940 45 remote write double word access cycle clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 msa0-13 t1 msrdb rcsb msd0-7 mswrb t7 t6 t5 0 n+ 5 n+ 6 n+ 7 n+8 n+9 n+10 n+ 11 t8 t9 t4 t3 t4 t3 t10 t11 t8 t9 t4 t3 t4 t3 n+12 n+13 n+ 14 n+ 15 symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+11 to rcsb deasserted 7 12 17 nsec t6 clock n+10 to msa deasserted 14 19 24 nsec t7 clock n+5 to msd valid 17 22 27 nsec t8 clock n+7 to msd deasserted 16 21 26 nsec t9 clock n+9 to msd deasserted 8 13 18 nsec t10 msa change to mswrb deasserted time t11 msa change to mswrb deasserted time 32kx8-70 sram remote read byte access cycle
W89C940 46 clk 1 2 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] data devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t2 t1 t4 t3 t5 n+4 n+7 n+8 n+ 9 t6 t7 n+5 n+6 symbol description min typical max unit t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec
W89C940 47 t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec remote read word access cycle clk 1 2 3 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t2 t1 t4 n+4 n+5 n+ 6 data t8 t3 t5 n+9 n+10 n+11 t6 t7 t7 t6 n+8 note: 1) the other timing requirements for pci signal are as the read transaction timing. 2) n=0,1,2,3,..... when local dma get the control of the bus, pci bus will insert wait state. wait state number is n. symbol description min typical max unit t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec
W89C940 48 t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec t8 msd hold time from clock n+8 nsec remote read double word access cycle clk 1 23 frame# ad[31::0] address bus cmd be#'s trdy# irdy# c_be#[3:0] data devsel# msrdb rcsb msa0-13 mswrb (read) msd0-7 0 t1 t4 t3 n+4 n+5 n+ 6 n+7 t2 t8 n+8 n+9 t5 t6 t7 t7 t6 t6 t7 t7 t6 t2 t8 n+10 n+11 n+12 n+13 n+14 symbol description min typical max unit t1 clock n+4 to rcsb and msa valid (note 2) 20 25 30 nsec t2 clock n+6 to msa valid 25 28 30 nsec t3 clock n+7 to rcsb deasserted time 10 15 20 nsec t4 clock n+4 to msrdb valid 22 27 30 nsec t5 clock n+7 to msrdb deasserted time 15 20 25 nsec t6 msd setup tim to clock n+6 7 nsec t7 msd hold time from clock n+6 0 nsec t8 msd hold time from clock n+8 nsec remote write byte access cycle
W89C940 49 clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 msa0-13 t1 msrdb rcsb msd0-7 mswrb t4 t3 t5 t6 0 n+ 5 n+ 6 n+ 7 n+8 n+9 t7 symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+5 to msd valid 7 12 17 nsec t6 clock n+7 to msd deasserted 14 19 24 nsec t7 msa change to mswrb deasserted time 17 22 27 nsec t8 clock n+7/ n+9 to msd deasserted 16 21 26 nsec t9 clock n+9 to msd deasserted 8 13 18 nsec remote write word access cycle
W89C940 50 clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 t5 msa0-13 t1 msrdb rcsb msd0-7 mswrb t4 t3 t7 t6 t8 0 n+ 5 n+ 6 n+ 7 n+8 n+9 n+10 n+ 11 t9 t4 t3 t10 t11 note: 1) the other timing requirements for pci signal are as the read transaction timing. 2) n=0,1,2,3,..... when local dma get the control of the bus, pci bus will insert wait state. wait state number is n. symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+10 to rcsb deasserted 7 12 17 nsec t6 clock n+9 to msa deasserted 14 19 24 nsec t7 clock n+5 to msd valid 17 22 27 nsec t8 clock n+7 to msd deasserted 16 21 26 nsec t9 clock n+10 to msd deasserted 8 13 18 nsec t10 msa change to mswrb deasserted time t11 msa change to mswrb deasserted time
W89C940 51 remote write double word access cycle clk 12 3 frame# ad[31::0] address bus cmd data be#'s trdy# irdy# c_be[3:0]# data be#'s devsel# t2 msa0-13 t1 msrdb rcsb msd0-7 mswrb t7 t6 t5 0 n+ 5 n+ 6 n+ 7 n+8 n+9 n+10 n+ 11 t8 t9 t4 t3 t4 t3 t10 t11 t8 t9 t4 t3 t4 t3 n+12 n+13 n+ 14 n+ 15 symbol description min typical max unit t1 clock n+5 to msa, rcsb, and msd valid (note 2) 17 22 27 nsec t2 clock n+7 to msa valid 14 19 24 nsec t3 clock n+6 to mswrb valid 9 14 19 nsec t4 write pulse width 4 9 14 nsec t5 clock n+11 to rcsb deasserted 7 12 17 nsec t6 clock n+10 to msa deasserted 14 19 24 nsec t7 clock n+5 to msd valid 17 22 27 nsec t8 clock n+7 to msd deasserted 16 21 26 nsec t9 clock n+9 to msd deasserted 8 13 18 nsec t10 msa change to mswrb deasserted time t11 msa change to mswrb deasserted time
W89C940 52 local read cycle clk 1 2 3 4 5 6 7 8 msrdb rcsb msa0-13 mswrb (read) msd0-7 t2 t1 t4 t8 t3 t5 t6 t7 t7 t6 symbol description min typic al max t1 clock 1 to rcsb and msa valid (note 2) 4 8 12 t2 clock 3 to msa valid 20 24 28 t3 clock 6 to rcsb deasserted time 4 8 12 t4 clock 1 to msrdb valid 8 12 16 t5 clock 6 to msrdb deasserted time 8 12 16 t6 msd setup tim to clock 3 24 28 32 t7 msd hold time from clock 3 24 28 32 t8 msd hold time from clock 8 local write cycle clk 12 3 0 1 2 3 4 56 7 t2 t5 msa0-13 t1 msrdb rcsb msd0-7 mswrb t7 t6 t8 t9 t3 t4 t3 t4 t10 t11 symbol description min typic al max
W89C940 53 t1 clock 1 to msa and rcsb valid 16 20 24 t2 clock 4 to msa valid 4 8 12 t3 clock 3 to mswrb valid 4 8 12 t4 write pulse width 20 24 28 t5 clock 6 to rcsb deasserted 20 24 28 t6 clock 6 to msa deasserted t7 clock 1 to msd valid t8 clock 3 to msd deasserted 8 12 16 t9 clock 5 to msd deasserted 8 12 16 t10 msa valid to mswrb deasserted 64 68 72 t11 msa valid to mswrb deasserted 40 44 48
W89C940 54 32kx8-220 bprom/ flash memory read cycle clk frame# ad[31::0] trdy# irdy# c_beb[3:0]# devsel# msa14/l msa[9:0] msa[13:10] bpcsb msrdb msd[7:0] 0 1 23 4 5 67 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 t1 t2 t3 t4 t5 t6 t7 t8 t9 t10 t11 t12 t9 t10 t11 t12 symbol description min typical max unit t1 clock 4 to msa14/l valid 8 13 18 nsec t2 clock 5 to msa14/l deasserted time 8 13 18 nsec t3 clock 6 to msa bus valid 8 13 18 nsec t4 clock 14 to msa bus valid 8 13 18 nsec t5 clock 23 to msa deasserted 8 13 18 nsec t6 clock 4 to msa high nibble valid 8 13 18 nsec t7 clock 6 to bpcsb valid 15 20 25 nsec t8 clock 25 to bpcsb deasserted 7 12 17 nsec t9 clock 8/ clock 17 to msrdb asserted time 15 20 25 nsec t10 clock 13/ clock 22 to msrdb deasserted time 8 13 18 nsec t11 msd setup time from clock 13 7 nsec t12 msd hold time from clock 15 0 nsec note: 1) the other timing requirements for pci signal are as the read transaction timing. 2) bprom/flash memory access could be byte, word or double word access. the timing is the same.
W89C940 55 file5
W89C940 56 aui/utp timing aui transmit timing (end of transmit) symbol description min. max. unit ttoh transmit output high before idle 200 ns ttoi transmit output idle time 8000 ns aui/utp receive timing (end of receive) symbol description min. max. unit t eo p 1 end of packet received hold time after logic "1" (note 1) 200 ns t eo p 0 end of packet received hold time after logic "0" (note 1) 200 ns note 1: this parameter is specified by design and is not tested. ttoi 0 ttoh 10 txp/n txp/n 101 11 rxp/xrdp rxn/xrdm rxp/xrdp 00 teop1 teop0 rxn/xrdm
W89C940 57 tpi transmit timing (end of transmit) 01 teth1 1 teth1 tpdp tpdm tpdp tpdm symbol description min. max. unit t eth1 end of packet transmitted hold time 1 (tpdp/m) (note 1) 250 ns link pulse timing tlpi tlpw tpdp tpdm symbol description min. max. unit t l p i link output pulse interval 8 24 ms t l p w link output pulse width 80 120 ns
W89C940 58 serial eeprom timing symbol description min. max. unit t1 eecs asserted to sk 500 ns t2 eecs hold from sk 0 500 ns t3 msd2 off time 500 600 ns t4 msd2 on time 500 600 ns t5 msd2 clock period 1 1.2 s t6 msd1 set up time to msd2 high 500 600 ns t7 msd1 hold time from msd2 high 500 600 ns t8 msd0 valid from msd2 high 300 ns t2 t1 t5 eecs t6 msd2 msd1 msd0 t8 t3 t7 t4 (sck) (do) (di)
W89C940 59 ac timing test conditions parameter test condition supply voltage (v dd /v ss ) 5v 5% temperature 25 c/70 c input test pattern levels (ttl/cmos) gnd to 4.0v input rise and fall times (ttl/cmos) 5ns input and output pattern reference level (ttl/cmos) 1.5v input waveform level (diff) -350 to -1315 mv input and output waveform reference levels 50% point of the differential tristate reference levels float (v) + 0.5v note 1: these parameters are specified by design and are not tested. output load the above specifications are valid only if the mandatory isolations are correctly employed and all differential signals are taken to the aui of the pulse transformer. note 1: load capacitance employed depends on output type. for 3sl, mos, tpi, aui: cl=50 pf. for 3sh, och: cl=240 pf. note 2: specifications which measure delays from an active state to a high-z state are not guaranteed by production test, but a re characterized using 240 pf and are correlated to determine true driver turn-off time by eliminating inherent r-c delay times in measurements. note 3: sw1=open for push pull outputs during timing test. sw1=vcc for vol test. sw1=gnd for voh test. sw1=vcc for high-z to active low and active low to high-z measurements. sw1=gnd for high-z to active high and active high to high-z measurements. sw1 (note 3) vcc 0.1uf input device under test rl = 2.2k output cl (note 1,2)
W89C940 60 pin capacitance ta = 25 c f = 1 mhz symbol parameter typ unit c in input capacitance 7 pf c out output capacitance 10 p derating factor output timing is measured with a purely capacitive load of 50pf or 240pf. the following correction factor can be used for other loads (this factor is preliminary only): derating for 3sl, mos = -0.05 ns/pf. derating for 3sh, ocl, tpi = -0.03 ns/pf. aui transmit test load note: in the above diagram, the tx+ and tx- signals are taken from the aui side of the pulse transformer. the pulse transformer used for all testing is a 100 h +/-0.1% pulse engineering pe64103. package dimensions dop don r=270 r=270 r=78
W89C940 61 100 pins pqfp he e hd d e b symbol a1 a2 b c d e e hd he l l1 y @ dimension in inch dimension in mm 0.004 min 0.112 + 0.005 + + + 0.012+ 0.004 - 0.002 0.006+ 0.004 0.551 0.787 0.026 + + + + 0.740 0.976 0.047 0.095 0.004 max 0.008 0.008 0.012 0.012 0.006 0.005 0.005 - 0.002 0 -------- 12 0.102 min 2.845 + 0.127 + + + 0.350+ 0.102 - 0.051 0.152+ 0.102 14.000 20.000 0.650 + + + + 18.796 24.790 1.194 2.413 0.102 max 0.203 0.203 0.305 0.305 0.152 0.127 0.127 - 0.051 0 -------- 12 @ c l1 l a2 a1 d y

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