PyUSB backend not accessible

python pyusb
vj85 picture vj85 · Mar 1, 2011 · Viewed 13.5k times · Source

hey i am trying to run the simple script available in the tutorial;. the usb is getting imported but when i try to search the device i get the following error,please help

>>> dev=usb.core.find()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python27\lib\site-packages\usb\core.py", line 819, in find
    raise ValueError('No backend available')
ValueError: No backend available

Answer

smattmyers picture smattmyers · May 10, 2011

You need to install libusb-1.0, libusb-0.1, or openusb as a backend to pyusb. Is this a Windows machine?

If so, you can download a simple installer here: http://www.craftedge.com/products/libusb.html

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