On Sun, Jun 1, 2014 at 8:10 AM, Xiaofan Chen <xiaofanc@xxxxxxxxx> wrote:
> I think you hit one of WinUSB's limitation.
>
> - with WinUSB configured to point to my composite device
> (ie DeviceID = "VID_0403&PID_7C38"), this fails after 32 iterations
> (way down in the guts of libusb - basically after 32 iterations it runs
> out of valid interfaces).
>
> - with WinUSB configured with two interfaces (ie DeviceID_0 =
> "VID_0403&PID_7C38&MI_00" and DeviceID_1 =
> "VID_0403&PID_7C38&MI_01"), this run without any issues.
>
> To use WinUSB as the driver for the USB composite device parent,
> you have to claim the first interface first (interface 0, or channel A).
> Ref:
> http://msdn.microsoft.com/en-us/library/windows/hardware/ff540245(v=vs.85).aspx
>
> Again, libusbk.sys does not have such limitation, you should
> try libusbk.sys instead (you will need libusbK.dll).
This may not be correct. libusb Windows backen will try to
auto-claim the default interface.
--
Xiaofan
--
libftdi - see http://www.intra2net.com/en/developer/libftdi for details.
To unsubscribe send a mail to libftdi+unsubscribe@xxxxxxxxxxxxxxxxxxxxxxx
|
