How Do I Configure the Beagle USB Protocol Analyzer to Capture Every LFPS Reset?

Question from the Customer:

I’m using the Beagle USB 5000 v2 SuperSpeed Protocol Analyzer - Standard Edition, and I have a question about triggering. How can I set the Beagle USB 5000 v2 analyzer to automatically capture every LFPS (Low Frequency Periodic Signaling) reset?

Response from Technical Support:

Thank you for your question! With our Data Center Software, you configure both pre-trigger and post-trigger settings, which are described in the following sections.

Capturing and Triggering Data

The following sections provide introductions to capturing and triggering data. For more information, please refer to the USB Monitoring section of the Data Center Software User Manual.

Capture Settings

Capture settings are configured in the Capture Settings dialog. In the example shown below, LPFS and Training traffic are captured and the all other data is dropped.

Capture Settings with Data Center software

Device Settings

In the Device Settings dialog, the proportions of data captured by pre-trigger and post-trigger is configured by sliding the Capture Buffer setting.

Configure data storage with Data Center software

  • The orange color of the bar represents the buffer for pre-trigger.
  • The blue color of the bar represents the buffer for post-trigger.

Note: when Infinite Capture is selected, the captured data is streamed to the computer. This configuration is useful for capturing data for extended periods. The total amount of data that can be stored depends on the RAM of the computer.

For details about the how the pre-trigger and post-trigger captures work, please refer to the Capture Control Window section of the Data Center Software User Manual.

Set Trigger to Capture LFPS

To trigger on capturing LFPS traffic, you can use the Simple Matching system from the Device Settings window:  Select Additional Settings and then select the USB 3.0 Matching tab.
Configure USB 3.0 Simple Trigger

To trigger the capture on LFPS traffic, check only the boxes for Upstream and Downstream LFPS under Sources.  Then under Actions, check the box for Capture Trigger.

Filter to Find LFPS

Once you’ve become capturing data and streaming it in the transaction log, you can filter to find LFPS packets.  To display all the Low Frequency packets, you can check the LFPS option in the LiveFilter tab, which is located in the Navigator pane of the main interface of the Data Center Software.

We hope this answers your question. Additional resources that you may find helpful include the following:

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