DMA buffer size

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Anonymous
Not applicable

Dear forum members,

   

 

   

I experimented bulk transfer speed with DMA buffer 32KB and 16 burst endpoint, and I got a speed 262MB/s.

   

 

   

What is the relation between DMA buffer size and burst size?

   

 

   

Is there any delay at buffer changing time? If not, I think CyUSB driver can't manipulate DMA machanism efficiently.

   

 

   

Best Regards,

   

HC

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2 Replies
Anonymous
Not applicable

Hi,

   

I didn't quite understand your question with regards to the buffer changing and DMA manipulation of CyUSB.sys.

   

Which buffer changing are you talking about? on the host side or device side?

   

Regards,

   

Anand

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Anonymous
Not applicable

Hi Anand,

   

I changed device side buffer size up to 48KByte.

   

and buffer size seems to be set up to 64K-1 byte. Right?

   

Another question, If an CRC error occured at bulk transfer, do the firmware and PC driver handle this error automatically?

   

Regards,

   

HC

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