Re: KMDF1.5: Reading from USB interrupt endpoints

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What you may be missing is the packet size. If your request to the interrupt endpoint is larger than what the device is returning, and the device happens to be returning a multiple of its MaxPacketSize, then your request will not complete as it is waiting for more data from the device.


"Johan Paul" <johan.paul@xxxxxxxxx> wrote in message news:NNW1k.13020$_03.3524@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Thanks Doron for your answer! This makes me feel a lot better. Do you
have any ideas why I now seem to miss the completion routine although
the host controller ACKs the IN transaction? Do you know, for example,
if some host controllers would have issues with this? I am sure the same
code works, for example, inside VMWare (VMWare running XP32, Vista32
inside VMWare) but I tested this today on my AMD64 laptop with Vista32
installed on it and saw that the read never completes.

I thought I would try tomorrow to do the read operation synchronously to
see if that makes a differance.



--
Johan


you are not missing anything, you can read/write to an interrupt
endpoint using the same APIs that you read/write to an bulk endpoint

d


.

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