User`s guide

DataBus Arm Violations - There are 4 possible arm violations in this tool. The examples below show cases where the
Arm Delay could be set improperly. If you encounter one of these cases, change the 'Arm Delay' and reacquire the
measurements.
The first is shown in the following figure. In this case, the histograms have tall, main peaks but, on the right side,
the short distributions trail off close to a full UI to the left. This is an arm violation that is caused by the arm plus
day falling very close to an edge of the data.
The second example is shown in the following figure. Here you can see that both distributions are on the right side
of the mean clock line (shown in red). This occurs when the arm violation is creating a condition where the left
most data histogram (see DataBus theory of operation) is the clock-to-data plus one unit interval. This is evident in
the summary that would incorrectly report the 'Average Skew' of this data set as the Skew plus 1UI (note that in the
example, the offset from the center of the two peaks is an additional UI).
© WAVECREST Corporation 2005 Glossary
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