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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
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13 years ago

Of course you would have to modify the logic source and create a new module.

If you want to access that module both from the Nios II CPU and from a DMA controller, things get complicated. That complexity is now handled by the Qsys fabric that 'separates' the two masters accessing the same slave. If you hack the SPI source into an output-only SPI with waitrequest you should be able to connect both the CPU and the DMA controller, but you will have to re-write the software driver as well.