W89C940 Datasheet, PDF (23/61 Pages) Winbond – ELANC-PCI (TWISTED-PAIR ETHER-LAN CONTROLLER WITH PCI INTERFACE)

W89C940
RST#
at least
1usec
EEREAD
1usec
14.4usec
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 1.2µS. 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 1.2µS. 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.
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