Author Topic: enumration problem in usb video  (Read 8489 times)

jazzzz

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enumration problem in usb video
« on: July 26, 2010, 08:41:11 am »
hi,
i am developing an usb video class device,at the end of enumration step,after SetConfiguration,the host request interface string twice and then communication stopped,the host should send class-specific request,but my device receive nothing, it seems host meets error after received the interface string from the device.i attached the picture of the usb explorer got,could someone help me?


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Jan Axelson

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Re: enumration problem in usb video
« Reply #1 on: July 26, 2010, 10:00:02 am »
It looks like you have a "!" at Get Descriptor (Device). What does the device return for that request?

Jan

jazzzz

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Re: enumration problem in usb video
« Reply #2 on: July 27, 2010, 07:39:12 am »
it should double click USB video device icon on PC,then host start transfer class-specific request,such as probe and commit control request

Jan Axelson

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Re: enumration problem in usb video
« Reply #3 on: July 27, 2010, 11:23:51 am »
My question was: what does the protocol analyzer show for the traffic under Get Descriptor(Device)?

Jan