Instruction manual

PC24E/25E
Page 16
3.3 Main I/O Bus Backplane Connections
Connection to the computer is made through the 62 pin I/O bus connector (Pins B1 and A1
are at the bracket end of the board). Pin connections are shown in figure 9. For further
information please consult the technical reference manual for the host computer.
Ground <
B1 A1
< -I/OCHCK
+Reset <
B2 A2
<> SD7
+5Volts <
B3 A3
<> SD6
+IRQ2/9* >
B4 A4
<SD5
-5Volts <
B5 A5
<> SD4
+DRQ2 >
B6 A6
<> SD3
-12Volts <
B7 A7
<> SD2
-0WS <>
B8 A8
<> SD1 C
+12Volts <
B9 A9
<> SD0 O
Ground <
B10 A10
< I/OCHRDY 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
DCLK<>
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
+5Volts <
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
Figure 9 MAIN PC BUS BACKPLANE CONNECTOR PIN ASSIGNMENTS