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Altera_Forum's avatar
Altera_Forum
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16 years ago

The problem of SGDMA descriptor

Hi: I am trying to use the SGDMA to transfer data,but I find it's hard to write the descriptor.I spend o lot of time to read the desgin example SG-DMA,it's hard to be understand. Is there so...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Take a look at this software: http://www.nioswiki.com/exampledesigns/sgdma

Really though you shouldn't need to modify the structure directly, there is an API for creating descriptors and sending them to memory for the SGDMA to access. There are a lot of pitfalls you can run into since the SGDMA accesses the descriptors in memory so you have to be very careful how you synchronize between the CPU and SGDMA engine.