Teledyne LeCroy Summit Z3-16 PCI Express Multi-lane Exerciser User Manual - Manual (Page 36)

Teledyne LeCroy LTSSM Control
36 Summit Z3‐16 PCI Express Multi‐Lane Exerciser User Manual
When the Summit Z3‐16 is directed to any of the low power states, it should be brought
out to L0 first before directing it to another low power state. For example, If the Summit
Z3 is in L1, it can not be directed to L0s immediately, you need to first direct it to L0 and
from there to L0s.
Note: If the device under test (DUT) does not support Loopback mode, the Summit Z3 may not
correctly transition out of Loopback state and a Link Reset may be required.
4.2.4 LTSSM Arc Tests
The Summit Z3‐16 Exerciser has been developed to allow for testing of the different arcs
of the LTSSM. This list of tests is displayed in the LTSSM Arc Tests in the left pane. When
you select a test from the test list, its information is displayed in the adjacent right panel.
The information is in the form as follows:
Test: The name of the test.
Test Description: A brief description of the test.
PreRequisites: The expected state that this test is starting from.
Test Scenario: Explains the details of what the test will perform.
Expected DUT State Transitions: The LTSSM states that the Device Under Test is going
through.
These tests have different prerequisites that need to be met in order to be run. Tests that
have their prerequisites met and that are ready to be run are displayed in black. Tests that
do not have their prerequisites met will be grayed out in the list of tests and you will not
be able to run them if you select them. In order to run tests that do not have their
prerequisites met, you can view the prerequisites and/or the description of the test by
clicking on that specific test. From there, you can manipulate the link speed/width/state
of the exerciser to match the prerequisites so that the test is enabled to run.
For example, as shown in the LTSSM Control Dialog, the Summit Z3‐16 is linked up at
2.5GT/s (Gen1) so the first test is ready to be run but the second and third tests are
grayed out since they require 5.0GT/s (Gen2) and 8.0GT/s (Gen3) speeds.
To run a test, select the test and click Run. The LTSSM state transitions from the test will
be displayed in the LTSSM Log (the bottom pane).
4.2.5 LTSSM Log
After issuing a speed change, link width change, link state transition, and/or running any
LTTSM arc test, the LTSSM state transitions that occurred will be displayed in the LTSSM
Log. This log will accumulate the state transitions from different run tests and the results
from commands issued from the controls. You can clear this log by clicking the Clear Log
button and you can also save the log as a text file for future reference by clicking on the
Save Log button. Clicking the Save Log button will prompt open the save file dialog.