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USB low-full-high speed peripherals Forum Discussions

Anonymous
Not applicable

Hi! Anand!

   

 

   

1,In the endpoint descriptor,when in isochronous transfer the bmAttributes's bit 3:2 defines Synchronization Type as :No Synchronization/Asynchronous/Adaptive/Synchronous, what's the differences among them?  To maximrize the transfer speed, how to set it?

   

 

   

2,The bmAttributes's bit 5:4 defines Usage Type as :Data endpoint/Feedback endpoint/Implicit feedback Data endpoint, what's the differences among them?  

   

 

   

Thank you!

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Anonymous
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Looking at your question I assume you're talking about a specific USB class protocol and not generic USB protocol. Is my understanding right? If so please let me know the protocol  you're referring to, if you can provide me a link to the document you're referring it would be much better.

   

Regards,

   

Anand

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Anonymous
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        oh,I just be curious about it when I read the standard endpoint descriptor in USB specification's chapter 9.6.6. I don't know how to set the value. but I have transfered succesfully when set them to zero.Thank you! Anand.Best Regards.   
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Anonymous
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I've not really paid attention to this part of the spec. Section 5.12.4 (page 72) seems to explain this in detail.

   

Regards,

   

Anand

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