Teledyne LeCroy WavePro Automation Command User Manual

Page 246

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Automation Command and Query Reference Manual - Control Reference

example, there might be fewer 1 bits in Eye2 if the one state often lasted only 1 UI, more often than
the zero state lasted only 1 UI.

ShowBER

Bool

Shows the probability that the diamond in the center of the eye will be violated. For a good signal this
should be less than 1e-12, possibly much less.

Description

ShowExtinctionRatio

Bool

This parameter only applies to optical signals, which have vertical units of Watts, and will not produce
a value on waveforms with other vertical units such as Volts.

Description

ShowEyeAmplitude

Bool

EyeAmplitude are the difference between top and base deteminded from the slice in the middle of the
eye (see app.SDA2.EyeMeasure.SliceWidth). See also EyeHeight.

Description

ShowEyeCrossing

Bool

Shows the crossing level as a percent of the eye height. If the crossing level is very far from 50% the
parameter may not be able to find it, in which case it will display an error status icon (something other
than a green check) and its status will include the bit meaning "Not an NRZ Eye"; the value it shows
will be 50% but the status indicates that value is not valid. If the status is OK, then the value is
meaningful.

Description

ShowEyeHeight

Bool

EyeHeight is [EyeOne level minus 3 sigma] minus [EyeZero level plus 3 sigma], where sigma is found
from the distribution of hits in the persistence map in the vertical slice about the center that is
analyzed (See app.SDA2.EyeMeasure.SliceWidth). This number is always less than EyeAmplitude.
The subtraction of 3 sigma on each side is an attempt to show how much the eye will be open after a
couple of thousand UI are included; on each side there is a 0.1% probability of being closer to the
center than 3 sigma (assuming the distribution is Gaussian). This was meant to be a predictor, in the
days when sampling scopes built an eye with perhaps twenty sweeps per second. The speed of the
SDA2 means that more than several thousand UI can be included per second, so EyeHeight may not
longer be needed as a predictor of eye closure after a couple of thousand UI, since the SDA2 can
measure that very quickly.

Description

ShowEyeOneLevel

Bool

EyeOne is the "top" level, derived from the distribution of points in the vertical slice through the pmap
at the center of the screen (see app.SDA2.EyeMeasure.SliceWidth). See also EyeZero, and
EyeAmplitude.

Description

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918501 RevA

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