Fluke 9000A-Z80QT, Инструкция по эксплуатации

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ZSOQT
a.
Perform
a write
operation to the port A
direction register to set
all
lines of I/O
port
A
(PAO-PA7)
as
inputs. The write address
is 2081;
write data
is
00.
b.
Perform
a read
operation at the
port
A
data
register, address 2080,
while sequentially applying both
+5V
and ground to each of the
port
A
input
pins (pins 2-9 of U2!) and observing the mainframe display. The
mainframe should indicate each high and
low applied to the inputs of
port A.
7. Check
the output operation
of
port B
(contained in U22 and U24) by
repeating
step
5
and using address 2083 for the
port
B direction register,
and address 2082
for
the
port B
data
register.
8. Check the
input operation
of
port B,
line PB7 (MAINTSTAT) by
repeating
step
6. Use address 2083
for
the
port B
direction register and
write data
00 to set line PB7 as an input. Perform the looping read at
address 2082, and apply both
+5V
and ground to pin
12
of the shielded
cable connector.
9.
Check
operation
of the interval timer (contained in
U25
and
26) by
first writing 00
to address 2094 to reset the timer, then writing
OF
to
address 209C. Verify that the
m
output at
U20, pin
18,
goes low
in
response to the second write
operation.
10.
Check
for
the occurrence of the UUT ON signal (produced by the
timing circuits as a result of the low lRQ signal) at pin
19
of the
PCB—to-PCB connector,
by repeating step
9.
ll.
Check for the occurrence of the SYNC signal at pin
10
of the
shielded cable connector, by repeating step
9.
12.
Check both
address decoders by performing read operations at
addresses 0000, 2000, 3000, 4000, 5000, 6000, and 7000. Verify
that
the
respective decoder output
goes low when addressed.
13.
If
repairs have been made to the inoperative pod as a result of the
preceding checks,
reinstall the pod’s microprocessor and attempt self
test. If self test operates,
but
the pod fails, refer to Troubleshooting a
Defective Pod.
The troubleshooting
guidelines presented in the preceding
paragraphs are
intend ed to assist
in
the
isolation
of faults within the pod.
lf attempted
troubleshooting fails to reveal the pod fault,
return of the pod to the nearest
Fluke Service
Center
is
recommended. Refer to the mainframe Service Manual
for a list of Fluke Service Centers.
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