PORTS Forum

Ports and Interfaces => USB => Topic started by: jazzzz on July 26, 2010, 08:41:11 am

Title: enumration problem in usb video
Post by: jazzzz 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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Title: Re: enumration problem in usb video
Post by: Jan Axelson 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

Title: Re: enumration problem in usb video
Post by: jazzzz 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

Title: Re: enumration problem in usb video
Post by: Jan Axelson 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