User guide

Accumulation Parameters for Bit Comparison without USB 3.1

SKPOS

For detailed information on "Bit Comparison without USB3.1 SKPOS" accumulation

parameters, see “Accumulation Parameters” on page 382.

Eye Measurements

Eye Measurements - Concepts

The purpose of eye measurements is to measure the eye height and width of the

incoming data signal at specific alignment BER thresholds. This information is

displayed on a representation of an eye diagram.

Eye Measurements - Procedures

Eye measurements are made each time the Auto Align, Clock/Data Center, or 0/1

Threshold Center functions are used.

To analyze the results:

View the graph and table in the Eye Results window.

This window provides detailed information on the calculated eye. See “Eye

Measurements - Reference” on page 393.

Analyze the results by observing changes in the eye results due to the following

adjustments:

– Make changes to your device or measurement setup.

– Run auto-search functions at different BER thresholds.

This will allow you to see the eye margin at specific BERs and construct

basic eye contour information.

Change the sampling point in the Sampling Point Setup window. See

“Sampling Point Display” on page 202 for details.

7 Evaluating Results

392 Agilent J-BERT N4903B High-Performance Serial BERT