Hi,

I have been working with pyUSB (Python 2.6) for last couple of days on
Windows. It works great and I could access the auto-id reader within
no time.  However, there is this read command timing out issue which I
am unable to resolve. In fact it is a bit weird since it seem to work
when I parallely run the demo application of the same reader provided
by the manufacturer.  The device driver spec, code & error output are
below.

Any help in solving the problem?

Sridev

---------------------------device specs-----------------------

Device:
  Device class: 0
  Device sub class: 0
  Device protocol: 0
  Max packet size: 64
  idVendor: 4292
  idProduct: 33266
  Device Version: 256
  Configuration: 1
    Total length: 32
    selfPowered: 0
    remoteWakeup: 0
    maxPower: 200
    Interface: 0
    Alternate Setting: 0
      Interface class: 255
      Interface sub class: 0
      Interface protocol: 0
      Endpoint: 0x81
        Type: 2
        Max packet size: 64
        Interval: 0
      Endpoint: 0x1
        Type: 2
        Max packet size: 64
        Interval: 0

----------------------------code--------------------------------
import usb.core
import usb.util

dev = usb.core.find(idVendor=0x10c4, idProduct=0x81f2)

if dev is None:
    raise ValueError('No Device')

dev.set_configuration()

msg = [0x03, 0x02, 0x00, 0x03, 0x07, 0xD0, 0x03]

bytes = dev.write(0x01, msg, 0, 2000)

received = dev.read(0x81, bytes, 0, 5000)
---------------------------error output------------------------------

C:\ Python26>python.exe code.py
Traceback (most recent call last):
  File "code.py", line 34, in <module>
    received = dev.read(0x81, bytes, 0, 5000)
  File "C:\Python26\lib\site-packages\usb\core.py", line 624, in read
    self.__get_timeout(timeout)
  File "C:\Python26\lib\site-packages\usb\_debug.py", line 53, in do_trace
    return f(*args, **named_args)
  File "C:\Python26\lib\site-packages\usb\backend\libusb01.py", line 448, in bul
k_read
    timeout)
  File "C:\Python26\lib\site-packages\usb\backend\libusb01.py", line 531, in __r
ead
    timeout
  File "C:\Python26\lib\site-packages\usb\backend\libusb01.py", line 364, in _ch
eck
    raise USBError(errmsg)
usb.core.USBError: libusb0-dll:err [_usb_reap_async] timeout error
-----------------------------------------------------------------------------------------

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