SMC Networks SMC91C95 - Manual (Page 15)

15
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
REGISTER.
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.
2
3
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.
I External ENDEC - (nXENDEC pin tied low).
In this mode the pins are inputs used for
collision and carrier sense functions.