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Altera_Forum
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14 years ago

Ping-Pong Buffer with SGDMA

Hi, I would like to implement a SGDMA (stream-to-memory) to store blocks of sampled data in internal memory for signal processing. The implementation should be a PING-PONG-Buffer, so that one blo...
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Altera_Forum
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14 years ago

Dear BadOmen

thanks for the quick reply. I configured the DMA to get an IRQ after each descriptor completed, but the problem is, that I cannot find out in the ISR which descriptor caused the IRQ.

I set the owned by HW bit and configured the DMA not to clear it (PARK bit set). You suggested to change this and manually restart the DMA in the ISR. But what if data arrives from the streaming interface before the ISR has restarted the DMA? Wouldn't this mean that data will be lost?

Thanks

Michael