With the Beagle USB 5000 v2 Protocol Analyzer, How Do I Filter and Capture Only the LTSSM Transitions from a UVC USB Video Class Device and Save the Data on a Hard Drive?

Question from the Customer:

I am using the Beagle USB 5000 v2 SuperSpeed Protocol Analyzer to analyze a UVC (USB Video Class) device.

  1. I don't want to capture the UVC frame data - I only want to capture the LTSSM (Link Training Status State Machine) transitions. How can I filter that data?
  2. How can I trigger the capture whenever a specific state entry occurs on the LTSSM?
  3. In the product feature, it is mentioned that the "Maximum single file Capture Size is 25.6 GB".  I need to store and analyze more data than that - how can I save the USB traffic directly on may hard drive?

Response from Technical Support:

Thanks for your questions! You can definitely use the Beagle USB 5000 analyzer and the Data Center Software to filter and capture data. The Beagle USB 5000 analyzer offers two ways – using LiveFilter or capture. The versatile and easy to use Beagle Software API gives you the ability to save the data to your hard drive, through your own custom program.

The following sections provide the information that you requested.

 Beagle 5000 USB Superspeed protocol analyzer Data Center Software

Figure 1: Beagle 5000 USB v2 Protocol Analyzer

Figure 2: Data Center Software

Capturing LTSSM transmissions only:

Using the LiveFilter, you can filter a specific data pattern. Simply apply the filter to focus on your event(s) of interest, and disable the filter to view the context of the event. This way you can see all the transactions that occurred before and after the selected event. For details about using this feature, please refer to the section Filtering a Capture in the Data Center Software User Manual. Figure 3 below shows an example of using LiveFilter:

 Use Data Center Software to "trigger" data with filters
Figure 3: Using LiveFilter with the Data Center Software and a Beagle Analyzer

Triggering captures based on a specific LTSSM state:

The Beagle USB 5000 analyzer has the ability to capture data when certain events occur on the bus: data is only stored on the analyzer until the capture is triggered, and then it is downloaded to the analysis machine (computer). For details about the triggering feature and the LTSSM view, please refer to the sections Triggering a Capture and LTSSM View in the Data Center Software User Manual. We also have a tutorial video about viewing LTSSM:


Saving captured data to the hard drive:

The Beagle USB 5000 analyzer and the Data Center Software can stop the transaction and then save the transaction log to a TDC or a CSV file. By default, this data is only saved to the RAM of the computer. Use the Beagle Software API to create a custom program to save data to the hard drive on the fly. The API supports multiple operating systems and program languages, and program examples are provided so that you can customize them for your specific setup.

Additional resources that you may find helpful include the following:

We hope this answers your questions. If you have other questions about our protocol analyzers or other Total Phase products, feel free to email us at sales@totalphase.com or submit a request for technical support.

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