Tech Support > Microsoft Windows > Drivers > USB Device does not respond
USB Device does not respond
Posted by Arun on April 21st, 2008


Hi All:
I have a strange problem with my USB Device/Driver.
Ours is an NDIS-WDM driver. Normally Data traffic works fine.
But sometimes we see that, the packet sent from the driver is not received
by the H/W. We setup a completion routine and call IoCallDriver. Normally
everything works fine. but sometimes what we see is that data transffered in
not reached to the device and Completion Routine is also not getting called.
Looks like, the data transferred in traped in the Host controller driver.

Any Ideas on this?

Regards
Arun

Posted by chris.aseltine@gmail.com on April 21st, 2008


On Apr 21, 8:29 am, Arun <A...@discussions.microsoft.com> wrote:

You haven't given any details about your device but I'm assuming you
have a pair of bulk endpoints over which you exchange 802.3 frames.

If you aren't getting your completion routine called on a bulk OUT
transfer, it's because the device never ACKed all the data. Have you
looked on the wire with a bus analyzer? I bet you'd see indefinite
NAKing or other bus errors.

Posted by Arun on April 22nd, 2008


Hi Chris,
As you assumed, I have a pair of Bulk endpoints. And
Completion routine is not getting called on my BULK OUT Endpoint. This
happens after a long run. I will try to setup protocol analyzer to see if it
is indefinite NAK's or Bus Errors.

Thanks
Arun

"chris.aseltine@gmail.com" wrote: