Re: [ntdev] Difference between USB ISO babble and xtor error

Could you find a USB analyzer? I suppose your company would has such equipment. That would be helpful with your problem.

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Sent: ‎Wednesday‎, ‎July‎ ‎9‎, ‎2014 ‎9‎:‎51‎ ‎AM
To: Windows System Software Devs Interest List

Hi, Tim,

Thank you for your reply.

The 18433 divided into one 1153 BYTES, 15 1152 BYTES packets is the algorithm from
WDK 7600.16385.1 USBSamp sample driver.

Here 768 length in isopacket[i].length instead of 2304, I think it is also because of babble, cause isopacket buffer is only 1153/1152, it could only receive the first transaction DATA 2768, then second DATA1 is droped.

The test device is from Microsoft, MUTT device.

I am curious that when 1153/1152 case, why it response with 2 transaction instead of 3?

BTW:
from the
http://msdn.microsoft.com/en-us/library/windows/hardware/hh406225.aspx
<>

The MaximumPacketSize value indicates the maximum permitted size of the isochronous packet. The client driver can set the size of each isochronous packet to any value less than the MaximumPacketSize value.

It allowed the 1153/1152 case.


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