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Re: Read Pipe Asynchronous Question

 Thanks for replying, the endpoint is bulk type. I am not sure whether this 4096 is the maxpacketsize, but i am sure that the camera is reading the data at 4096 bytes per packet. And when i use the USB sniffer on windows, i get the packets with the size of 4096.

 

rgds

shejian..

Fernando Urbina <email@hidden>
04/21/2005 09:10 PM CST

To: She Jian Chia <email@hidden>
cc: email@hidden
bcc:
Subject: Re: Read Pipe Asynchronous Question


What type of endpoints does your camera have?  Your maxPacketSize of
4096 does not make sense for bulk or isochronous, so something is
amiss here.

--
Fernando Urbina
USB Technology Team
Apple Computer, Inc.

On Apr 21, 2005, at 8:49 PM, She Jian Chia wrote:

> I have create a userland USB driver for my USB camera. And when i
> use the
> read pipe asynchronous method to read the video frame continously from
> camera, the camera is able to do the reading with the max packet
> size(4096
> bytes for this case). But now the problem is, when i compare the
> fps to
> window's fps, i found the fps on mac is much more slower(the packet
> size is
> the same on both platform). So what i want to know it how can i
> increase
> the speed of reading from pipe. Hope someone here would enlighten
> me..Thanks!
>

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