Xgig Tuning And Equalization; Tuning - Viavi Xgig User Manual

Xgig Tuning and Equalization

Xgig Tuning and Equalization
Tuning and Equalization are procedures to optimize ports on the 6G SAS/SATA blades and
systems for your environment. When you connect the Xgig SAS Analyzer or Jammer in a new
environment (for example, after changing devices or cable length) we recommend that you run the
Tuning procedure below. If, after Tuning, the Analyzer or Jammer detects excessive signal
integrity issues, go on to adjust the Equalization settings. For more information about Tuning and
Equalization, see

Tuning

Tuning is used to fine-tune the sampling position in the data stream. The tuning function optimizes
the Xgig ports for the particular devices and channel in use, and maximizes the receiver margin to
ensure signal interoperability. Always perform Tuning after Equalization settings have changed.
Tuning can only be performed when the Analyzer ports are in
retiming would initiate an OOB sequence which would cause the user's devices to temporarily
stop sending traffic needed by the tuning algorithm.
Requirements for Tuning
1 All port-pairs to be tuned must be exchanging traffic in both directions. All ports will be tuned
at their respective data rate.
2 Use high link utilization, if possible.
If possible, use a stress pattern such as unscrambled CJTPAT; however, this is not required.
3
Initiate Tuning
Set up and connect all ports to be tuned so that they are exchanging traffic in both directions.
1
In TraceControl, create a domain and lock all ports to be tuned. Right-click the software LEDs
2
at the port level shown in the domain created for the 6G SAS/SATA blade or system, and
select
Xgig Analyzer User's Guide
"Technical Overview of Tuning and Equalization" on page
Change Equalization Settings
Chapter 3, Getting Started with Xgig TraceControl
Analog Passthrough
.
72.
mode. Digital
67