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Will the data be overwritten if I do not call CyU3DmaChannelGetBuffer() in time
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Will the data be overwritten if I do not call CyU3DmaChannelGetBuffer() in time

byeyear posted on 31 Dec 2011 11:46 PM PST
Top Contributor
29 Forum Posts

Hello,

When I use DMA mode CY_U3P_DMA_TYPE_MANUAL_IN to transfer data from host computer to cyusb3014, will the data be overwritten if I do not call CyU3DmaChannelGetBuffer() in time? For example, I allocate 8 buffer for dma, and generate 9 OUT token, but I do not read data from any dma buffer. Will the 9th transaction data overwrite the 1st transaction data?

Best, regards.

 

Re: Will the data be overwritten if I do not call CyU3DmaChannelGetBuffer() in time

aasi posted on 01 Jan 2012 11:03 PM PST
Cypress Employee
1073 Forum Posts

On the GPIF II side we've flags and on the USB side we've NRDY defined by USB specification which take care that packets are not lost. (Isochronous is the only transfer type which will run into data loss in your scenario but isochronous does come with the implied constraint that data loss will not affect the system).

Regards,

Anand



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