USB Inrush tool is grayed out - how do I use it?

Question from Jeremiah Gillis over on Kickstarter:
Is the USB Inrush tool supposed to be grayed out on 0.4.1? I am unsure how to activate it.

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Hi Jeremiah!

I have not yet documented how to use the USB inrush tool, so I’m not surprised that it is confusing. The USB inrush tool depends upon the official USBET20 from the USB-IF. USBET20 only runs on Windows, so the Joulescope software only supports USB inrush testing under Windows. First, download USBET20 from the USB-IF, then install it to the default path on your computer. You can then use the Joulescope software to collect and analyze data:

  1. Install the USB Front Panel (or use some other way to route USB current through Joulescope)
  2. Launch the Joulescope UI
  3. Click Tools and verify that USB Inrush is not grayed out
  4. Select ViewOscilloscope
  5. Select Current Rangeoff
  6. Connect the IN USB port to your host computer
  7. Connect the OUT USB port to your target device
  8. Ensure that the oscilloscope is streaming live data
  9. Select Current Range10 A
  10. Wait for a second (you only need 100 ms of data)
  11. Click Play button to stop live streaming
  12. Pan and zoom, until your desired range (at least 100 ms, but likely not more than 200 ms) is displayed onscreen. (now that the software has dual markers, I should add support there!)
  13. Click ToolsUSB Inrush
  14. Wait for USBET20 to launch Internet Explorer (for realz) to display the results. While the browser is open, you can navigate to the directory and copy out the data if you want.
  15. Close Internet Explorer

The official USBET20 test is normally performed with USB20CV. If you find that your device is failing because your computer is initializing it, then run USB20CV and its special USB stack on either another computer or a different root hub of the same computer.

Please reply if you have any questions or run into any issues. I intend to integrate this post into the Joulescope User’s Guide, so I really appreciate your feedback!

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Thank you Matt. I will try this out when I get a chance.

I get a “page cannot be displayed” error once IE opens. And the “temp/xxx” folder does not exist. Do I need to do anything to configure the USBNET tool?

Hi @anven and welcome to the forum! I don’t think that you should need to do anything special. The Python code creates that temporary folder, which should start with a “js_” prefix. The USBET is directly opening IE to that folder, so USBET is running. If you start the USBET tool on its own, does it run? If you can locate the “js_” temporary directory, you can also try providing the “inrush.csv” file directly to the USBET tool on the “Inrush Current” tab.

The Joulescope UI code to launch the USBET tool is pretty simple. On my machine, USBET does not return until you close Internet Explorer. If for some reason USBET closes immediately after calling Internet Explorer, then python would erase the temporary directory which would explain the behavior that you see. I could change this code to use a fixed, permanent directory rather than a temporary directory if this is the problem.

Thank you - that was it. I had a rogue instance of IE open and hiding in the task bar. Closing IE first solved the problem.

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