LeCroy Advisor, User Manual

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Chapter 9: Decode Requests USB Advisor User Manual
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9.3 General Options
Commands are transferred on USB using special control transfers called USB Device
Requests. The Analyzer can decode Device Requests as they are defined in the USB
specifications and various Device Class and Vendor specifications.
Each USB Device Request is sent using a Control Transfer. Each Control Transfer starts
with a SETUP transaction.
Decoding USB Device Requests
To decode a USB Device Request:
Step 1 Left-click the Control Transfer field or the SETUP field of the
USB Device Request to display the USB Device Request menu:
Note: The menus shown in this section are context-sensitive. You may see slightly
different menus.
Step 2 To refresh decoding, click Refresh Decoding for this Trace File. Use this option
to reanalyze all transactions.
Step 3 To use the previous decoding, click Load most recent decoding mapping .
This option loads the most recent mapping of endpoints/requests to decoding
types that was done on a previous trace. If the endpoints of the new trace are the
same as the last one mapped, the mappings are applied to the current trace. This
saves the user from having to constantly apply the mapping to a new trace every
time the application is restarted and a new trace created.
The ability to retain the mapping from trace to trace DURING an application
session already exists: the Keep Across Recordings button in the endpoint map
dialog. This new feature simplifies the process when the application has been
re-started.
Note: You can also change the format, color, and hidden status of fields, using the
same methods as in Display Options. (See Chapter 6, Display Options.)