W89C926 Datasheet, PDF (6/48 Pages) Winbond – PCMCIA ETHERNET NETWORK TWISTED PAIR INTERFACE CONTROLLER

W89C926 PENTIC+
Pin Description, continued
NAME
NUMBER
MSWR
86
Network Interface
TXO+, -
60, 59
RXI+, -
58, 57
TX+, -
RX+, -
CD+, -
X1
X2
64, 63
66, 65
68, 67
55
54
THIN
51
ACTLED
52
TYPE
O/TTL
DESCRIPTION
Memory Support Write:
MSWR is asserted by the PENTIC+ to strobe write data
into the on-board memory. Both SRAM and flash
memory use MSWR as the write command strobe.
O/DIF
I/DIF
O/DIF
I/DIF
I/DIF
I/XTAL
O/XTAL
O/TTL
O/TTL
Twisted Pair Transmit Outputs:
UTP differential output pair. A 1.21 KΩ precision resistor
should be shunted across these pins for signal pre-
equalization.
Twisted Pair Receive Inputs:
These inputs are fed into a differential amplifier which
passes valid data to the LCE core. A 100Ω precision
resistor should be shunted across these pins for
impedance matching.
AUI Transmit Outputs:
Differential transmit outputs. These pins should be con-
nected to 270 ohm external pull-down resistors.
AUI Receive Inputs:
Differential receive input pair from AUI interface.
AUI Collision Inputs:
Differential collision input pair from AUI interface.
Crystal Input:
Master 20 MHz clock input.
Crystal Feedback Output:
This pin should be connected to the crystal when a
crystal is used and should be left unconnected when an
oscillator is used.
Thin Cable Select:
This pin is high when the PENTIC+ is configured for thin
cable media. It can be used as a switch to DC-DC con-
verter for network media selection.
Activity:
This output asserts low for approximately 50 mS
whenever the PENTIC+ transmits or receives data
without collisions. This output can also be controlled by
the power-down state machine; refer to the descriptions
of the COR and CFA registers for more details.
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