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Altera_Forum
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15 years ago

Accessing custom component from DMA

In our design we have included a custom component into the SOPC design. The custom component (IMM, instance IMM_x) is connected to the write master port of a DMA. The DMA reads data from data_memory ...
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Altera_Forum
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15 years ago

If I remember correctly then those look like the correct flags to pass in. Typically I access the DMA directly using the register macros provided with the driver since I typically like my DMA overhead to be at a minimum. Usually it takes around four accesses to the slave port to get the DMA moving, using the driver it'll be much more and since it's not a scatter-gather DMA you can't hide that overhead.

Page 153 in this document explains setting up the channel in more detail: http://www.altera.com/literature/hb/nios2/n2sw_nii5v2.pdf