Teledyne LeCroy WavePro Automation Command - Manual (Page 229)

Automation Command and Query Reference Manual - Control Reference
SetToCenter Action
This Action cvar corresponds to the button "Start IsoBER Scan" on the Eye Diagram tab of the Eye
Measure menu's right side dialog. Sending this command causes the "Show IsoBER" checkbox to be
checked, and the IsoBER curves appear inside the opening of the Eye diagram. Each curve shows
what the eye opening should be to achieve a certain probability of signal instrusion inside that curve.
Description
' Visual Basic Script
Set app = CreateObject("LeCroy.XStreamDSO")
app.SDA2.EyeMeasure.SetToCenter
Example
ShowEyeMeasure Bool
This cvar corresponds to the "Enable Eye Meas." checkbox at the left of the Eye Measure menu.
Setting it to false turns off the eye diagram, any failure cursors and failure location waveforms. Setting
it to true re-enables those things, and they appear if their individual controls are set.
Description
' Visual Basic Script
Set app = CreateObject("LeCroy.XStreamDSO")
app.SDA2.EyeMeasure.ShowEyeMeasure = true
app.SDA2.EyeMeasure.ShowSimpleEye = true
app.SDA2.EyeMeasure.ShowMask = true
app.SDA2.EyeMeasure.ShowMaskFailures = true
Example
ShowFailLocation Bool
The best way to describe the feature this enables is to distinguish between this and
ShowMaskFailures. ShowMaskFailures is a simple mask test, it looks at the accumulated Eye
Diagram and draws red circle cursors around any sample that violates the mask. See
"ShowMaskFailures" for more detail on the simple mask test. "ShowFailLocation" is a feature that
helps you gain insight into the mask failures. As its name implies, it looks at every UI of the current
acquisition, and builds a list of which UI numbers contained at least one sample that violated the mask
(see app.SDA2.EyeMeasure.FailedList). Then, by selecting a number in that list, you can view the
segment of the waveform centered at the middle of the UI with the failure. The samples from that UI
are highlighted with yellow circles, instead of red circles. If there are a few points at opposite corners
of the mask, you can filter the list to show only UI with nearby failures
(app.SDA2.EyeMeasure.FailedSymbolsFilter), to easily check if all the failures at a corner were
caused by the same local bit pattern.
When ShowFailLocation is true, the setting of ShowFailures is irrelevent; the cursors are drawn by the
Mask Failure Locator feature and not by the simple mask test.
Description
ShowIsoBER Bool
Turns on contours showing eye closure at the same Bit Error Rate = Iso BER contours. These are
displayed on the Eye.
Description
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