User`s guide

In-depth theory
When making a propagation delay measurement, the instrument will measure various combinations of bit
clock edges to different data "periods". For example, a "101" transition would give a distribution of lower
values than a "110011" transition. Therefore, the resulting histograms will have many distributions
separated by the time of a Unit Interval (UI).
Each of these "unwanted" portions of the histogram are filtered out to yield only the positive
measurements not more than one UI from the Clock reference edge. Additionally, the output of the tool
shows the data transition closest to the bit-clock reference edge. An oscilloscope has a trigger delay.
© WAVECREST Corporation 2005 Section 4 - GigaView
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