Zenith Data Systems Z-171 PC Series Service Manual page 22

Page 2-5
Installation
Table 2-1 (continued): Bus Expansion Connector Pinout
PIN NUMBER SIGNALNAME DESCRIPTION
52 1Q7 Interrupt request 7. Assigned to parallel in-
terface.
53 1Q6 Interrupt request 6. Assigned to floppy con-
troller.
54 1Q5 Interrupt request 5. Assigned to external
drive controller.
59 1Q4 Interrupt request 4. Assigned to serial port
(configurable).
56 1Q3 Interrupt request 3. Assigned to serial port
(configurable).
57 DMACK2+* DMA acknowledge 2. Assigned to floppy
controller.
58 TC Terminal count. Goes high when terminal
count for any DMA channel is reached.
59 ALE Address latch enable. Generated by bus
controller to indicate valid processor ad-
dresses to the I/O channel.
60 +5 VDC +5 VDC bus.
61 MCLK A 14.31818 MHz oscillator.
62 GND Ground.
PIN 1
Figure 2-3: Expansion Connector