BUK IN DP burst not according to U3 Spec?

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Anonymous
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I found the FX3 will sometimes send 2 consecutive DPs, then wait for Host ACK. but according to USB3.0 spec 8.12.1.2 (BUK IN Transaction), device don't have to wait for Host ACK [BURST], so in my case Host will first send ACK with NumP=8, it means device is allowed to response with up to 8 consecutive DPs without waiting Host ACK. what is the reason of FX3 not following spec on this part? is it because the bandwidth of FX3 not enough? 

   

please see my attached file for more detail.

   

thanks.

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Anonymous
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 sorry, here is the log file

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Anonymous
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What is the host controller that you are using?.

   

Are you using a FX3 DVK with engineering sample on it?.

   

Regards,

   

sai krishna.

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Anonymous
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I am using TI TUSB7340 & NEC Host, but i don't think it is host issue. 

   

I have modified engineering sample to FullHD UVC, but the modification is just the bigger payload.

   

perhaps you could do the same at your end to see what's really happening.

   

BR,

   

Owen

   


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Anonymous
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Hi Owen Chang,

   

I don't think FX3 is waiting for the ACK from the host side.

   

It is just that the host controller is sending the ACK to FX3 before it recieves the total number of packets.

   

Regards,

   

sai krishna.

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