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Teledyne LeCroy Summit Z2-16 PCI Express Multi-lane Exerciser User Manual User Manual

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Chapter 4: Traffic Generation

Summit Z2-16 Exerciser User Manual

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Teledyne LeCroy

The Status bar at the bottom of the screen shows the current state of the PCI Express
Link. When the Link is down, it shows Detect. When it is up, it shows L0.

All of the intermediate link states, such as Polling and Configuration, are handled
automatically. In fact, after the Link=L0 command is executed and the LTSSM is alive,
the Exerciser attempts to keep the Link active just as any other PCI Express device does.
This includes handling of Recovery states and subsequent retraining events.

The next step is to enable flow control. This is done by executing the Link=InitFC
command. This causes the Exerciser to perform flow control initialization and, if enabled,
begin periodic transmission of Update_FC DLLP's. If the Link connect toolbar button was
used, the flow control initialization happens automatically.

By using these basic commands, the complicated process of link training is managed
automatically. The Link is now trained and the script execution can now focus on sending
TLP packets.

Script Execution

As mentioned above, each time a script is executed, the configuration settings for the
Exerciser are reprogrammed. When the Start generation button is pressed, the script is
uploaded to the Exerciser hardware and executed immediately. Progress of the script can
be tracked in the status bar at the bottom of the screen. Subsequent executions of the
same script do not require upload of the script to the Exerciser, however, as mentioned
above, the generation options are still reprogrammed.

Script execution can be throttled using Wait commands inserted directly into the script.
Waits can be time based, require receipt of certain packet types, or can even require
User input from the GUI.

After the script is complete, any enabled PCI Express behaviors, such as SKIP insertion,
Flow control, and ACK generation, continue. This allows you to run multiple scripts, one
after another, without interrupting the Link state.