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question on L138 USB cppi dma rx

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Hi,

 1.   I  would like to know if i can use cppi dma in RNDIS mode to realize a USB mass storage device in rx. I see the startware  use transparent mode for rx. But transparent mode would cause a number of interrupts in receiving. Is there any examples i can take as a reference?

  2.  I read the spruh77a carefully and found that cppi dma would trigger the interrupt only after receiving the whole packet, then i can offload the whole packet once in the isr.  Do i have any misunderstanding in cppi dma's RNDIS mode? 

 3.  I've not used the cppi dma before, and CPU take the responsibility to offload data from fifo after a WRITE10 command, but only 0x400 bytes at most can be received at one time. It seems that a buffer overrun occurs when the packet length is larger than 0x400 bytes. Dose this trouble can be avoid by using cppi dma?

Huang 


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