Expansion Connector - Zenith Z-171 Series Service Manual

Page
2-5
Installation
Table 2-1 (continued): Bus Expansion Connector Pinout
PIN NUMBER SIGNAL NAME DESCRIPTION
52
IQ7
Interrupt request 7. Assigned to parallel in-
terface.
53
IQ6
Interrupt request 6. Assigned to floppy con-
troller.
54
IQ5
Interrupt request 5. Assigned to external
drive controller.
55
IQ4
Interrupt request 4. Assigned to serial port
(configurable ).
56
IQ3
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 110 channel.
60
+5VDC
+5 VDCbus.
61
MCLK
A 14.31818 MHz oscillator.
62
GND
Ground.
PIN 1
Figure 2-3: Expansion Connector