Fluke 9000A-Z80QT, Инструкция по эксплуатации

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ZBOQT
4.
Check for operation2f_the
interval
timer
and timing circuits
by
observing pin
18
of U20
(IRQ)
for
a low-going output
each time a read
operation is
executed. If the
IRQ signal is
present, check
for
a SYNC
signal at pin
10
of
the shielded cable connector, and for a UUT ON signal
at pin
19
of
the PCB-to-PCB connector. The absence of these signals
allows the pod to communicate with the mainframe,
but
prevents the
latches
from
detecting addresses,
data, and control signals sent to the
UUT (or self test socket). Failure
of
these signals may also prevent data
read from the UUT from reaching the pod microprocessor.
5-10. SELF TEST CODE
1
Ifa
self test produces
a failure code of
1,
one
or
more
of
the following failures is
indicated:
0 UUT power sensing circuit failure
0 Control line(s) cannot be driven
0
Address.hne(s) cannot
be
driven
0
Data
line(s) cannot be driven
To
further isolate the trouble, proceed
as
follows:
1.
Check the operation of the UUT power sensing circuit by verifying
the
+5V
UUT supply at the
ribbon
cable connector and 0V on the Power
Fail line. Check the Power Fail line
of
the PCB-to-PCB connector, and if
necessary, at the shielded cable connector.
2.
Perform
a
write operation; use OFFO
for
the address and UP
for the
data.
a.
If the mainframe indicates a control line error, examine the entire
mainframe display to determine the stuck control line(s). While
looping on the
error, use the probe
or
a scope to locate
the
point
of
control
line failure.
b.
If the mainframe indicates an address line
error,
note the failed
address line(s) indicated on the mainframe display. While looping on
the
error, use the probe or a scope to locate the point
of
address
line
failure.
0.
If the mainframe indicates a
data
line error, note the failed line(s)
indicated on the mainframe display. While looping on the error, use
the probe
or a scope to locate the point
of
failure.
3. Repeat
steps 2b and
2c
using
FOOF
for the address and F0 forthe data
to check address and data lines in the opposite state.
5-13