Agilent Technologies 1670E Series, User Manual

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Logic Analyzer Concepts
Transitional Mode Theory (1660E/ES/EP-series only)
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.