SMC Networks SMC91C95 User Manual

Page 12

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12

DESCRIPTION OF PIN FUNCTIONS

PIN NO.

NAME

SYMBOL

TYPE

DESCRIPTION

nIOIS16

PCMCIA - Active low output asserted
whenever the SMC91C95 is in 16 bit mode,
and “Enable Function” bit in the ECOR
register is high, nREG is low and A4-A15
decode to the LAN address specified in I/O
Base Registers 0 and 1 in PCMCIA attribute
space.

88

nI/O Read

nIORD

IS with

pullup

Input. Active low read strobe used to access
the SMC91C95 IO space.

87

nI/O Write

nIOWR

IS with

pullup

Input. Active low write strobe used to access
the SMC91C95 IO space.

86

nMemory
Read

nMEMR

IS with

pullup

ISA - Active low signal used by the host
processor to read from the external ROM.

nOutput
Enable

nOE

PCMCIA - Output Enable input used to read
from the COR, CSR and attribute memory.

24

nModem
Reset

nMRESET

O4

Reset output to Modem. Asserted whenever
RESET pin is high, internal POR is active, or
SRESET bit is high (MCOR bit 7).

18

Modem
Interrupt

MINT

I with pull

down

Interrupt input from Modem. Reflected in
INTR (CSR bit 1) and asserts the appropriate
interrupt pin if enabled.

23

nModem
Chip Select

nMCS

O4

Chip select output to modem.

17

Modem
Ready

MRDY

I with pullup

Modem ready input. Low indicates the modem
is not ready, either after reset or exiting from
stop or sleep modes.

27

nModem
Powerdown

nMPWDN

O4

Powerdown output to modem controller. This
pin is active (low) when either the PWRDWN
bit (CSR bit 2) is set or the modem is disabled
(not configured).

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