[pyusb-users] PyUSB with libusb1.0

[Somsubhra T. <s_t...@re...>]

I am very new to PyUSB and any help from PyUSB experts will be highly appreciated. My 
intention is to communicate with the CY7C67300 usb controller on XUPv5-lx110T (Xilinx)  
board. I have installed pyusb and libusb in win7-32bit machine using "pip install " command. I am using python2.7. I was following the tutorial written in 
"https://github.com/pyusb/pyusb/blob/master/docs/tutorial.rst". 

When I applied the following few lines in IDLE Python GUI, 
---------------------------------------------------------------
import usb.core
import usb.util

# find our device
# dev = usb.core.find(idVendor=0xfffe, idProduct=0x0001)
dev = usb.core.find(find_all=True, bDeviceClass=7)
print dev
----------------------------------------------------------------

I have got the following response : 

======================= RESTART: E:\My_Python\test1.py =======================


I typed in the following in python prompt and got this response below:
>>>dev.set_configuration()

Traceback (most recent call last):
  File "", line 1, in 
    dev.set_configuration()
AttributeError: 'generator' object has no attribute 'set_configuration'

This I confirmed using 
>>>print dir(dev)

['__class__', '__delattr__', '__doc__', '__format__', '__getattribute__', '__hash__', 
'__init__', '__iter__', '__name__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', 
'__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'close', 'gi_code', 
'gi_frame', 'gi_running', 'next', 'send', 'throw']

Again I typed in the following and got a response:
>>> usb.core.show_devices(verbose=True, find_all=True)

Traceback (most recent call last):
  File "", line 1, in 
    usb.core.show_devices(verbose=True, find_all=True)
  File "C:\Python27\lib\site-packages\usb\core.py", line 1287, in show_devices
    strings += "%s\n\n" % str(device)
  File "C:\Python27\lib\site-packages\usb\core.py", line 731, in __str__
    configuration = self.get_active_configuration()
  File "C:\Python27\lib\site-packages\usb\core.py", line 875, in get_active_configuration
    return self._ctx.get_active_configuration(self)
  File "C:\Python27\lib\site-packages\usb\core.py", line 102, in wrapper
    return f(self, *args, **kwargs)
  File "C:\Python27\lib\site-packages\usb\core.py", line 236, in get_active_configuration
    self.managed_open()
  File "C:\Python27\lib\site-packages\usb\core.py", line 102, in wrapper
    return f(self, *args, **kwargs)
  File "C:\Python27\lib\site-packages\usb\core.py", line 120, in managed_open
    self.handle = self.backend.open_device(self.dev)
  File "C:\Python27\lib\site-packages\usb\backend\libusb1.py", line 786, in open_device
    return _DeviceHandle(dev)
  File "C:\Python27\lib\site-packages\usb\backend\libusb1.py", line 643, in __init__
    _check(_lib.libusb_open(self.devid, byref(self.handle)))
  File "C:\Python27\lib\site-packages\usb\backend\libusb1.py", line 593, in _check
    raise NotImplementedError(_strerror(ret))
NotImplementedError: Operation not supported or unimplemented on this platform
>>> 

I have googled "NotImplementedError:.....", but did not understand much from the serach- 
results.

I have checked the IBackend class in usb/backend/__init__.py file. All the usb host 
transaction functions in IBackend are implemented as 
_not_implemented(self.enumerate_devices)

What am I missing out?

Rgds, ST