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Message
From: "Marc Reinig" <mreinig@p...>
Date: Tue, 7 Oct 2003 10:40:20 -0700
Subject: RE: [usb] Get more descriptor data from device than it is available
> -----Original Message-----
> Subject: [usb] Get more descriptor data from device than it is available
>
> If the host requests more descriptor bytes than it is available,
> what is the expected behaviour from the device?
The device sends as much as it has or as much as the host has asked, which
ever is less.
> If the device
> sends only the available bytes, what is expected behaviour of
> host?
The host knows the rules and would not be surprised. In general though,
unless you are writing host drivers, never make assumptions about what the
host might do on a control endpoint. A device should do whatever the hosts
says, and not try to out guess it.
Marc Reinig
System Solutions
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