HP 54750A, User Manual, Page: 362 / 478

The General Function Menus
Limit T est Menu
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Measurement
Not Found
The Meas Not F ound softkey allows you to determine what action the limit
test takes when the instrument cannot perform a measurement. F or example ,
if the instrument cannot nd an edge on a rise time measurement, what
action should the limit test take?
If the instrument is stopped, you can cycle through the selections to see the
limit test results in more detail.
NNNNNNNNNNNNNN
Fail F ail is used in cases where the instrument cannot make a
measurement. F or example , when an edge is expected to be
present but is not found. The fail mode is used for most
applications .
The total number of waveforms is incremented, and the total
number of failures is incremented.
NNNNNNNNNNNNNN
Pass Y ou might use the pass parameter when triggering on one
event and measuring another event that may not occur on
every trigger . F or example , in a communications system,
you may want to trigger on the clock and test the rise times
of edges in the data stream. However , there may be no
way to guarantee that a rising edge is present to measure
in the data stream at every clock edge . By using the pass
parameter , the limit test will not log a failure if an edge is
not found in the data stream.
If the measurement cannot be made , then the total number
of waveforms measured is incremented, but the total
number of failures is not incremented.
NNNNNNNNNNNNNNNNNNNN
Ignore Ignore is similar to P ass , except that the totals for the
number of waveforms and failures are not incremented.
Therefore , the total indicates the number of tests when the
measurement was available .
K ey Path 4 Limit test 5
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Fail when
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Meas not found
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fail or
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pass or
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ignore
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