SMC Networks SMC91C95

DESCRIPTION OF PIN FUNCTIONS

PIN NO. NAME SYMBOL TYPE DESCRIPTION

10 nReceive

LED nRXLED OD16 Internal ENDEC - Receive LED output.

Receive

Clock RXCLK I with pullup External ENDEC - Receive clock input.

11 nLink LED nLNKLED OD16 Internal ENDEC - Link LED output.

Transmit

Data TXD 0162 External ENDEC - Transmit Data output.

111 Enable

EEPROM ENEEP I with pullup Input. This active high input enables the

EEPROM to be read or written by the

SMC91C95. Internally pulled up. Must be

connected to ground if no serial EEPROM is

used. In PCMCIA mode, a parallel EEPROM

is required if no serial EEPROM is used.

115 nEnable 16

Bit nEN16 I with pullup Input. When low the SMC91C95 is configured

for 16 bit bus operation. If left open the

SMC91C95 works in 8 bit bus mode. 16 bit

configuration can also be programmed via

serial EEPROM (In ISA Mode only) or via

software initialization of the CONFIGURATION

101

102

Crystal 1

Crystal 2

XTAL1

XTAL2

Iclk An external parallel resonance 20 MHz crystal

should be connected across these pins. If an

external clock source is used, it should be

connected to XTAL1 and XTAL2 should be

left open.

123

124

AUI Receive RECP

RECN

Diff. Input AUI receive differential inputs.

AUI

Transmit TXP/nCOLL

TXN/nCRS Diff.

Output Internal ENDEC - (nXENDEC pin open). In

this mode TXP and TXN are the AUI transmit

differential outputs. They must be externally

pulled up using 150 ohm resistors.

IExternal ENDEC - (nXENDEC pin tied low).

In this mode the pins are inputs used for

collision and carrier sense functions.