Specifications

CHAPTER 3
I/O Specifications
XD Connector 53
then connecting a hardware key to the expansion card. The XD connector may also be
used for a sound expansion card.
The XD connector is a 50-pin connector, JAE part number KX15-50K3E9. Table 3-9 shows
the pin assignments for this connector.
Table 3-9 XD connector pin assignments
Pin number Signal Description
1 ISA IRQ(3) ISA interrupt request 3
2 SA(10) S address bit 10
3 ISA IRQ(4) ISA interrupt request 4
4 SA(9) S address bit 9
5 ISA IRQ(7) ISA interrupt request 7
6 SMEMW S memory write
7 IOCHK I/O check
8 IRQ(9) Interrupt request 9
9 DREQ(6) DMA request 6
10 MINUS 12 V –12 V power supply
11 DACK DMA acknowledge
12 SMEMR S memory read
13 REFRESH Refresh
14 +12 V +12 V power supply
15 IOR I/O read
16 AEN Address enable
17 DREQ(3) DMA request 3
18 OSC Oscillator
19 RESETDRV Reset drive
20 +5 V +5 V power supply
21 SA(7) S address bit 7
22 XD(7) Buffered data bit 7
23 SA(4) S address bit 4
24 0WS 0 write strobe
25, 29, 45 GND Ground
26 IOW I/O write
27 ISA Detect Detect external device on ISA bus