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Re: Fwd: ReadPipeTO timeouts not working?

At 1:28 PM -0500 10/24/06, robert engels wrote:

On a side note to that, are the kernel drivers doing any buffering on the pipes. What I mean is that if I do not have an outstanding ReadPipe or ReadPipeAsync on the pipe, and the devices sends data, is it lost? Or is there some lower level buffer or protocol that would not allow this to happen (i.e. the device is prohibited from sending if there are no outstanding reads).

The device can't send data if the host does not ask for it. That's basic USB protocol. The host does not ask for data if the driver does not have an outstanding read (also to USB spec). There is no buffering, its read straight off the wire into the buffer provided (usually).

If the device can't hold all the data it has and is not read before it loses data, that's a problem for the device and the driver to work out.
--
Barry Twycross
email@hidden
---
USB, it's not a Dyslexic BUS. (Thanks to TC.)
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 >Fwd: ReadPipeTO timeouts not working? (From: robert engels <email@hidden>)



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