Other Transitional Timing Considerations - HP 1660CS-Series User Manual

Transitional Mode Theory

Other transitional timing considerations

Other transitional timing considerations
Pod pairs are independent In single run mode each pod pair runs
independently. This means when one pod pair fills its trace buffer it will
not shut the others down. If you have a pod pair with enabled data lines
and no transitions on its lines, you get a message "Storing transitions
after trigger for pods nn/nn." In repetitive run mode, a full pod pair waits
2 seconds, then halts all other pod pairs.
Increasing duration of storage In the 125-MHz mode a transition on
any one of the 34 bits in a sample (if they are all turned on) will cause
storage. Reducing the number of bits that are turned on for any one pod
pair will more than likely increase data storage time.
Separating data lines which contain frequent transitions from lines with less
frequent transitions also helps. When doing this, be sure to cross pod pair
boundaries. It does not help to move fast lines from pod 1 to pod 2; fast lines
must be moved to pod 3, a different pod pair.
In the 250-MHz mode a transition on any one of 17 bits (half-channel) each
sample (if they are all turned on) will cause storage.
Invalid data The analyzer only looks for transitions on data lines that
are turned on. Data lines that are turned off store data, but only when
one of the lines that is turned on transitions. If the data line is turned on
after a run, you would see data, but it is unlikely that every transition
that occurred was captured.
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