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Xgig Tuning and Equalization Chapter 3, Getting Started with Xgig TraceControl
Xgig Analyzer User’s Guide 69
b
The blade is replaced
c A cable is changed
d
Device is replaced (drive, HBA, expander, etc.)
e Device transmitter settings are changed (for example, de-emphasis is increased)
2
Upon completion of tuning, if some ports still receive errors, follow the instructions below to
modify the equalization on that particular port and attempt to tune again. If problems persist,
shorten the cables or adjust the emphasis and/or amplitude settings on the transmitter, if
possible.
3
Settings persist across an Xgig chassis reboot or power cycle.
Restore Tuning Defaults
To restore the original factory settings for tuning, press the
Restore
button on the web page. The
restore function will also cause all link rates to return to the original factory settings. The tuning
process will automatically apply both the Tuning results and the latest Equalization settings at the
end of the tuning process.
Equalization
The general rules for choosing the appropriate Equalization setting are listed below. The suggested
settings for Equalization for each port and speed are provided in Table 4. Note that the legend
below Table 4 shows the precise meaning of cable lengths and de-emphasis settings at the input
device.
1 At data rates of 1.5000 Gbps and 3.0000 Gbps the equalization setting can be left to None .
2
The Equalization process is performed for the selected ports on a blade. All locked ports are
selected by default, but you can choose to unselect any of those ports. If Equalization is not
required for a particular port at a particular speed, make sure it is set to
None
.
3 At 6.0000 Gbps, you may need to change the equalization setting. Situations where
equalization settings should be changed include when the transmitting device has low or no
emphasis, or where a long cable is used. See Table 4 for a list of the suggested settings for
equalization based on de-emphasis of the signal and the length of the cable.
4 Always perform the Tuning procedure after you have completed Equalization. In the unlikely
event you believe the analyzer is receiving false errors after performing both Equalization and