Tricky USB device.

[David Gilbert]

>>>>> "Bernd" == Bernd Walter <ticso at cicely12.cicely.de> writes:

Bernd> Yes - you must use 1 - there is only one out-endpoint.  0x81 is
Bernd> for receiving data and endpoint 0 is the mandandory control
Bernd> endpoint.  Interrupt Endpoints are not variable in size.  Both
Bernd> interrupt endpoints are 8 Bytes, so you must read and write
Bernd> exact 8 Bytes per transfer - 5 shouldn't work for USB compliant
Bernd> devices.

I took your earlier advice and just opened ugen0.1 O_RDWR.  I've tried
sending 5 and 8 byte strings to it without effect.  To make the 8 byte
strings, I added spaces to the end of my 5 byte strings.  I've also
got a proper multitester now to verify operation.

Bernd> Depends on the device's firmware.  I wouldn't be surprised if
Bernd> the whole device just hangs after receiving bogus data - it
Bernd> seems to be broken in many points.  But it may block if the
Bernd> device has nothing to send.  An easy way to check out is using
Bernd> tools like usbdevs -v and see if it hangs when accessing this
Bernd> device.

usbdevs -v and udesc_dump both operate fine after trying this.

Dave.

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