Connector Pin Assignments B-1 3

ISA Expansion Bus Connectors

The expansion slot signals, voltages, and grounds are supplied through the bus

connectors. The following table provides the pin assignments for the ISA

expansion bus.

ISA Expansion Slot Pin Assignments

Pin Direction Signal Pin Direction Signal
A1 Input IO CHCK# B1 Gr ound Ground
A2 Input/Output SD7 B2 Reset RESET
(RESDRV)
A3 Input/Output SD6 B3 Power +5V
A4 Input/Output SD5 B4 Input IRQ9
A5 Input/Output SD4 B5 Power -5V
A6 Input/Output SD3 B6 Input DRQ2
A7 Input/Output SD2 B7 Power -12V
A8 Input/Output SD1 B8 Input SRDY#
(N0WS#)
A9 Input/Output SD0 B9 Power +12V
A10 Input IO CHRDY B10 Ground Ground
A11 Output AEN B11 Output SMEMW#
(SMWTC#)
A12 Input/Output SA19 B12 Output SMEMR#
(SMRDC#)
A13 Input/Output SA18 B13 Input/Output IOW# (IOWC#)
A14 Input/Output SA17 B14 Input/Output IOR# (IORC#)
A15 Input/Output SA16 B15 Output DACK3#
A16 Input/Output SA15 B16 Input DRQ3
A17 Input/Output SA14 B17 Output DACK1
A18 Input/Output SA13 B18 Input DRQ1
A19 Input/Output SA12 B19 Input/Output REFRESH#
A20 Input/Output SA11 B20 Output BCLK
A21 Input/Output SA10 B21 Input IRQ7
A22 Input/Output SA9 B22 Input IRQ6
A23 Input/Output SA8 B23 Input IRQ5
A24 Input/Output SA7 B24 Input IRQ4
A25 Input/Output SA6 B25 Input IRQ3
A26 Input/Output SA5 B26 Output DACK2#
A27 Input/Output SA4 B27 Output TC