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Altera_Forum
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13 years ago

SPI with DMA is not working?

Hi, everyone I am using SPI Master Core on FPGA to transmit data to SPI slave (offboard device). I want to use DMA to free my NIOS for other tasks during SPI data transfer. My Idea is NIOS...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

I found another issue.

just for testing I shut off RX path and use DMA to stream 5 bytes data to SPI TX holding register. but no success!

I could only send 2 bytes and then I got a TOE.

SPI has signal "readyfordata" als flow controll. But I can not find any signal somehow like that on DMA write master, which leads DMA send the 5 data to SPI without considering if SPI is ready or not.

How does DMA controll data flows?

Thanks