Description Of Pin Functions - SMC Networks SMC91C95 Product Manual

PIN NO. NAME
113
35, 36, Address 0-
38-43, 15
45-50,
52, 53
54 Address 16
nFlash
Memory
Write
55 Address 17
nFlash
Memory
Chip Select
56 Address 18
57 Address 19
Card Enable
1
34 Address
Enable

DESCRIPTION OF PIN FUNCTIONS

SYMBOL TYPE
nROM/ I/O4 with
nPCMCIA pullup
A0-A15 I
A16 I
nFWE O4
A17 I
nFCS O4
A18 I
A19 I with pullup
nCE1
AEN I with pullup
nREG
9
DESCRIPTION
This pin is sampled at the end of RESET.
When this pin is sampled low the SMC91C95
is configured for PCMCIA operation and all
pin definitions correspond to the PCMCIA
mode. For ISA operation this pin is left open
and is used as a ROM chip select output that
goes active when nMEMR is low and the
address bus contains a valid ROM address.
Input address lines 0 through 15.
ISA - Input address line 16.
PCMCIA - Output. Flash Memory Write
Enable used for programming the attribute
memory. Goes active (low) when nWE=0 and
WRATTRIB=1 (in ECOR bit 3).
ISA - Input address line 17.
PCMCIA - Output. Flash Memory Chip Select
used to access attribute memory. Goes active
(low) when nREG=0, nCE1=0 and A15=0.
Input address line 18.
ISA - Input address line 19.
PCMCIA - Card Enable 1 input. Used to
select card on even byte accesses.
ISA - Address enable input. Used as an
address qualifier. Address decoding is only
enabled when AEN is low.
PCMCIA - Attribute memory and IO select
input. Asserted when the card attribute space
or IO space is being accessed.