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Appendix B: Troubleshooting Problems
Xtium2-CXP PX8 User's Manual
Diagnostic Tool Self-Test Window
Click the Start button to initiate the board memory self-test sequence. A healthy board will pass all
memory test patterns.
Figure 51: Diagnostic Tool Main Window
Camera Input Eye Diagram Monitor
Eye Diagrams allow the user to evaluate visibly the signal integrity between camera data lanes or
between different cable sets. This tool does not provide specific measurements but will help to
identify signal noise or jitter associated with bad cables or overly long cables.
The screen capture below shows a camera with four data lanes, where each digital signal is
repetitively sampled and overlaid over itself, showing relative low-high transitions of the differential
signal. The blue center area (eye surface) seems similar between each lane, typical for a good
cable set.
The closure (collapse or horizontal shortening) of the eye surface would indicate problems such as
poor signal to noise, high cable capacitance, multipath interference, among many possible digital
transmission faults.
Figure 52: Eye Diagram