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Date: Mon, 27 Jun 2011 16:34:21 +0200
From: Luca Pizzamiglio <l.pizzamiglio@bally-wulff.de>
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Cc: freebsd-usb@freebsd.org
Subject: Re: Read from bulk end point
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Hi,

the buffer size mitigates the pre-fetch, but could not remove it all... 
Setting 1 as buffer size, the pre-fetch is reduces as 3 wMaxPacketSize 
IN transaction on the bus, but could not avoid it.

There is a way to disable pre-fetch features? Or better, HPS could you 
point me where is implemented? (just to save time studying source code!)

Is the prefetch also enabled for Interrupt end point? maybe I could have 
push to correctly redesign this USB board...

thanks in advance!

Luca

On 06/27/11 13:20, Hans Petter Selasky wrote:
> On Monday 27 June 2011 13:14:55 Luca Pizzamiglio wrote:
>> It was strange, because for other endpoints I don't see this kind of
>> behavior.
>
> Hi,
>
> That is perhaps because they send less data than wMaxPacketSize.
>
> --HPS