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A-12 Connector Pin Assignments
ISA Expansion Bus Connector Pin Assignments
The expansion slots have the following specifications:
n
I/O port addresses 378 through 37F, 2F8 through 2FF, and 3F8 through 3FF are
used by the system board (can be disabled).
n
8 MHz bus timing.
n
8/16-bit data transfer, DMA controlled.
n
System board ignores the MEMCS16 assertion signal during I/O cycles and the
IOCS16 signal during memory cycles.
n
IOCHRDY is never asserted by the system board.
n
The system board does not support bus master initiated refresh.
n
8-bit write transfers at odd addresses. Data is mirrored on high and low bytes.
All PC/AT signals, voltages, and grounds are supplied through the bus connectors. There
are no active components on the ISA backboard. Table Appendix A-22 shows the connec-
tor and pin assignments for the ISA expansion slots.
Table Appendix A-22 ISA Expansion Slot Pin Assignments
Pin
Direction
Signal
Pin
Direction
Signal
A1
Input
IOCHCK
B1
Ground
GND
A2
Input/Output
SD07
B2
Output
RSET DRV
A3
Input/Output
SD06
B3
Power
+5V
A4
Input/Output
SD05
B4
Input
IRO09
A5
Input/Output
SD04
B5
Power
–5V
A6
Input/Output
SD03
B6
Input
DRQ2
A7
Input/Output
SD02
B7
Power
–12V
A8
Input/Output
SD01
B8
Input
0WS
A9
Input/Output
SD00
B9
Power
+12V
A10
Input
IOCHRDY
B10
Ground
GND
A11
Output
AEN
B11
Output
SMEMWR
A12
Input/Output
SA19
B12
Output
SMEMRD
A13
Input/Output
SA18
B13
Input/Output
IORD
A14
Input/Output
SA17
B14
Input/Output
IOWR
A15
Input/Output
SA16
B15
Output
DACK3
Summary of Contents for PowerMate 466M
Page 10: ...Contents xiii ...
Page 176: ...Connector Pin Assignments A 15 ...