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Altera_Forum's avatar
Altera_Forum
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12 years ago

SGDMA Transfers only 20 bytes

Hi, I am having an issue using the SGDMA core with a NIOS core and uCOSII. I think the code sets up the descriptor correctly (this to tx a packet out the TSE MAC): the source is the transmit b...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

So if I understand you correctly, the packet size is correct, but the end of the data isn't correct. It could be either because your software begins to overwrite the data before the DMA is finished sending it, or it could be a data cache coherency problem. If your CPU has a data cache, ensure you flush the data buffer before you start the SGDMA.

Are you using Altera's driver with the Interniche stack, or your own implementation?