NotImplementedError: Operation not supported or unimplemented on this platform

[0hotpotman0]

Hi

I run the pyusb(1.2.1 version) library on windows 10, the python version is 3.8.0, there got an error in function "ctrl_transfer()", my code is quite simple, via serial to transfer the address to the register via that function,

import time
import usb.core
import usb.util

#---------------------wIndex bit format------------------------#
#bit 7      6       5       4       3       2       1       0
#    1      1       1       1       GPIO.3  GPIO.2  GPIO.1  GPIO.0


#

PID = 0xea60
VID = 0x10c4

dev = usb.core.find(idVendor=VID, idProduct=PID)
if not dev:
        print("CP2104 was not found!")
        exit(1)
print("Yeeha! Found CP2104")

reqType = 0x41
bReq = 0xFF
wVal = 0x37E1

while True:

        wIndex = 0xffff
        print("toggling On")
        dev.ctrl_transfer(reqType, bReq, wVal, wIndex, [])
        time.sleep(1)
        print("toggling Off")
        wIndex = 0x00ff
        dev.ctrl_transfer(reqType, bReq, wVal, wIndex, [])
        time.sleep(1)

then I got the error as below:

Yeeha! Found CP2104
toggling On
Traceback (most recent call last):
  File "cp2102n_gpio_tset.py", line 29, in <module>
    dev.ctrl_transfer(reqType, bReq, wVal, wIndex, [])
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\core.py", line 1071, in ctrl_transfer
    self._ctx.managed_open()
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\core.py", line 113, in wrapper
    return f(self, *args, **kwargs)
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\core.py", line 131, in managed_open
    self.handle = self.backend.open_device(self.dev)
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\backend\libusb1.py", line 804, in open_device
    return _DeviceHandle(dev)
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\backend\libusb1.py", line 652, in __init__
    _check(_lib.libusb_open(self.devid, byref(self.handle)))
  File "C:\Users\Fenyi\AppData\Local\Programs\Python\Python38\lib\site-packages\usb\backend\libusb1.py", line 600, in _check
    raise NotImplementedError(_strerror(ret))
NotImplementedError: Operation not supported or unimplemented on this platform

It can find my port, but the function 'ctrl_transfer' look like does not support Windows, please help.

Best regards

[jonasmalacofilho]

The error message, the fact that it's coming from libusb_open, and that you're dealing with a CP21xx device, suggests that your issue is the need to install a libusb-compatible driver.

https://github.com/libusb/libusb/wiki/Windows#How_to_use_libusb_on_Windows