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Altera_Forum
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15 years ago

SGDMA Core loop problem - setting CHAIN_COMPLETED

Hello. OK, I have cut my project back so it consists of just the NIOS, SGDMA, SDRAM controller, and an onchip memory component. If I set up the SGDMA to transfer a set of bytes between t...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I've had descriptors in SDRAM in the past and don't understand why it isn't working... the next step would be to put SignalTap probes all around the SGDMA core and look at what it is doing...

Are you sure that the transfer isn't done? If the CPU has a data cache, the contents of both the descriptor and the memory buffers could be hidden by the cache if you don't invalidate it (or go around it when looking at the memory contents).