Pyusb on windows - no backend available

Question

I\'m trying to have my python application interface with an NFC device via USB. The best option seems to be pyusb, but I can\'t get it to connect to the libusb backend. I ke

Answer 1

There's a simpler solution.

Download and unpack to C:\PATH the libusb-1.0.20 from download link

Then try this line:

backend = usb.backend.libusb1.get_backend(find_library=lambda x: "C:\PATH\libusb-1.0.20\MS32\dll\libusb-1.0.dll")

dev = usb.core.find(backend=backend, find_all=True)

Depending on your system, try either MS64 or MS32 version of the .dll

Update of 17/01/2020, after a request to share more code:

import usb.core
import usb.util

from infi.devicemanager import DeviceManager
dm = DeviceManager()
devices = dm.all_devices
for i in devices:
    try:
        print ('{} : address: {}, bus: {}, location: {}'.format(i.friendly_name, i.address, i.bus_number, i.location))
    except Exception:
        pass


import usb.backend.libusb1

backend = usb.backend.libusb1.get_backend(find_library=lambda x: "C:\\libusb-1.0.20\\MS32\\dll\\libusb-1.0.dll")
dev = usb.core.find(backend=backend, find_all=True)

def EnumerateUSB():    #I use a simple function that scans all known USB connections and saves their info in the file
    with open("EnumerateUSBLog.txt", "w") as wf:
        counter = 0
        for d in dev:
            try:
                wf.write("USB Device number " + str(counter) + ":" + "\n")
                wf.write(d._get_full_descriptor_str() + "\n")
                wf.write(d.get_active_configuration() + "\n")
                wf.write("\n")
                counter += 1
            except NotImplementedError:
                wf.write("Device number " + str(counter) + "is busy." + "\n")
                wf.write("\n")
                counter += 1
            except usb.core.USBError:
                wf.write("Device number " + str(counter) + " is either disconnected or not found." + "\n")
                wf.write("\n")
                counter += 1
        wf.close()