Teledyne LeCroy USBTracer_Trainer - Users Manual - Manual (Page 344)

Chapter 12: Traffic Generation (3.0 Exerciser) USB Protocol Suite User Manual
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LeCroy Corporation
12.11 USB 3.0 Electrical Test Modes
In the Electrical Test window, you can use Loopback mode and Compliance mode.
To access the Electrical Test window, you must connect to the Voyager system.
12.11.1 Loopback Mode
The Voyager USB 3.0 Electrical Test window supports entry to the Polling.Loopback
substate. For receiver testing, the device under test (loopback slave) is placed in a
special test mode and echoes back a predefined loopback pattern. The Voyager system
can initiate this special mode (loopback master) and generate the basic loopback pattern.
The Voyager automatically monitors the received traffic for bit errors.
Full compliance testing requires the addition of jitter tolerance measurements to the
loopback stream. Specialized equipment, such as LeCroy's PERT
Receiver Tolerance Test system, should be used to introduce jitter and perform the full
electrical layer compliance testing process.
Loopback Mode test procedure
Step 1 Connect the DUT to the Exerciser port:
For Device Loopback: Attach DUT to Port A
For Host Loopback: Attach DUT to Port B
Step 2 Set recording options:
For Device DUT Loopback: Set Voyager as Host Emulator
For Host DUT Loopback: Set Voyager as Device Emulator
Step 3 In the Misc USB 3.0 tab, uncheck the Filter Out Logical Idles & SKPs option.
Initiating loopback mode requires that the DUT successfully link trains with the
Voyager exerciser. Verify that the link reaches U0 by pressing the Record button
and looking at traffic for LUP/ LDN link commands.