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[Q] Anyone able to get 1ms USB interrupt pipe polling interval happening?

OSR_Community_UserOSR_Community_User Member Posts: 110,217
I have a USB device which has an interrupt endpoint whose descriptor
specifies a 1ms polling interval. However, Windows only seems to be able to
effectively poll this endpoint once every 2 milliseconds.

That is, Windows *does* poll every frame so long as the device responds only
with a NAK. However, Windows always fails to generate an IN token for the
frame immediately following an actual DATA0 or DATA1 response from the
hardware. Therefore, we can only receive data every 2 milliseconds.

Has anyone gotten Windows to poll an interrupt pipe on every frame (once a
millisecond)? I have seen other reports on the net, but nothing definitive,
that hint that Windows cannot actually do 1ms polling of interrupt pipes.

- Matt

PS: I am seeing this behavior on Windows 2000. Have not tried Windows 98
yet.
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