PC27E
Page 15
5.3
Main I/O Bus Backplane Connections
Connection to the computer is made through the I/O channel main bus. The pin designations
are shown in Figure 4, but for further information please consult the technical reference
manual for the host computer.
62 Pin Connector (Pins B1 and A1 are at the bracket end of the board)
Ground <
B1
A1
<
-I/O CHCK
+ Reset <
B2
A2
< >
SD7
+5 Volts<
B3
A3
< >
SD6
+IRQ2/9* >
B4
A4
<
SD5
-5 Volts <
B5
A5
< >
SD4
+DRQ2 >
B6
A6
< >
SD3
-12 Volts<
B7
A7
< >
SD2
-0WS
< >
B8
A8
< >
SD1
C
+12 Volts<
B9
A9
< >
SD0
O
Ground <
B10
A10
<
I/O CHRDY
M
S
-SMEMW<
B11
A11
< >
AEN
P
O
-SMEMR<
B12
A12
< >
SA19
O
L
-IOW
< >
B13
A13
< >
SA18
N
D
-IOR
< >
B14
A14
< >
SA17
E
E
-DACK3< >
B15
A15
< >
SA16
N
R
+DRQ3 < >
B16
A16
< >
SA15
T
-DACK1< >
B17
A17
< >
SA14
S
+DRQ1 < >
B18
A18
< >
SA13
S
I
-DACK0< >
B19
A19
< >
SA12
I
D
CLK
< >
B20
A20
< >
SA11
D
E
+IRQ7 < >
B21
A21
< >
SA10
E
+IRQ6 < >
B22
A22
< >
SA9
+IRQ5 < >
B23
A23
< >
SA8
+IRQ4 < >
B24
A24
< >
SA7
+IRQ3 < >
B25
A25
< >
SA6
-DACK2< >
B26
A26
< >
SA5
+T/C
<
B27
A27
< >
SA4
+BALE <
B28
A28
< >
SA3
+5 Volts<
B29
A29
< >
SA2
OSC
<
B30
A30
< >
SA1
Ground <
B31
A31
< >
SA0
* Note: Pin B4 is IRQ2 for an XT
Pin B4 is IRQ9 for an AT which is re-directed as IRQ2
FIG. 4 - MAIN PC BUS BACKPLANE CONNECTOR PIN ASSIGNMENTS
