Fluke 9000A-Z80QT, Инструкция по эксплуатации

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Z8OQT
NOTE
When troubleshooting
a
pod, perform
looping tests
of
the most
simple type (such as reads
and
writes as Opposed to
ROM and
RAM
tests) to
reveal
afault
symptom. A
synchronizedprobe
can
then be
used
to trace a
fault
once such a looping test
has
it isolated.
5-9.
SELF TEST CODE 0
If a self test produces a failure code of
0,
a UUT read
operation has failed, and
one or more of the following problems is
indicated:
UUT power sensing circuit failure
Control
line(s)
cannot be driven
Address line(s) cannot be driven
Wrong
data
read
To
further
isolate the trouble, proceed
as
follows:
1.
Check 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 at the PCB-to—PCB
connector, and
if
necessary, at the shielded cable
connector.
2.
Perform
a
read operation. Use address
OFFO
if using the self test
socket as the UUT. (The self test socket sends the upper address byte to
the
data
lines. During self test, read operations at
OFFO
and
FOOF
take
place.) Use any address
containingknowndata if using some
other UUT.
3.
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.
c.
If the data
read, indicated on the mainframe display, is not 0F
when using the
selftest
socket, or is
not identical to the known data
of
the UUT used for this test, a data
line or address line failure
is
indicated. Determine the failed line(s) from the display and locate the
point
of failure using the synchronized probe or a scope while
performing a looping read
operation.
Repeat
steps 2b and
20
at
different
addresses and for different data in
order
to toggle each of the address and data
lines.