How Do I Successfully Connect the Beagle USB 5000 v2 SuperSpeed Protocol Analyzer to an Embedded Device where the System Provides No VBUS?

Question from the Customer:

I read the article Monitoring an embedded USB with a Beagle USB Protocol Analyzer and it looks like what I need to start my project. I’ll be using the Beagle USB 5000 v2 SuperSpeed Protocol Analyzer - standard edition. But before I get started, I have a few questions:

  1. It looks like I can connect the embedded device to monitor to either the Beagle USB 5000 host or the device port – or does it matter which port is used?
  2. My target device has 3.3V USB D+/D- voltages. Does that affect anything? Do I need to change the thresholds for the Beagle analyzer to work with that device?
  3. The device does not provide the 5V for the VBUS – how can I make this work with the Beagle analyzer?

Response from Technical Support:

Thanks for your questions! The Beagle 5000 v2 SuperSpeed analyzer is an excellent tool for capturing, displaying and filtering High Speed Data. It will easily work with your setup.

Beagle 5000 USB Superspeed protocol analyzer Monitoring an Embedded System with a Beagle USB 480 Protocol Analyzer

Figure 1: Beagle USB 5000 v2 SuperSpeed Protocol Analyzer - Ultimate Edition.

Figure 2: Connecting the Beagle Analyzer to an Embedded Device

Regarding your questions:

  1. As shown in Figure 2 above, you can connect your target embedded device to either the Beagle 5000 analyzer target host port or to the target device port.
  2. The D+/D- lines carry the differential signal. A level of 3.3V is compatible with the Beagle USB 5000 analyzer – you don’t need to make any changes.
  3. The Beagle USB 5000 analyzer USB 2.0 VBUS is 5V. This standard is specified in the USB 2.0 specification. To recognize that a host is present, the Beagle analyzer must detect 5V on the VBUS. There are two ways to make this work if the target device does not provide the VBUS voltage:
    • You can provide the 5V to the Beagle analyzer from an external source, such as a power supply.
    • Alternatively, if you are using the Data Center Software, you can set up the Data Center Software to capture traffic data without VBUS voltage. To do so, enter the following command in the Data Center Command Line window:  device({'usb.vbus_override': True}).  For more information about Command Line Options, please refer to the Data Center Software User Manual.

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 if you already own one of our devices and have a technical question, please submit a request for technical support.

Leave a Reply