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Altera_Forum
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8 years ago

altera DMA stuck in busy state

Hi, I was trying to transfer data between DDR and FPGA through DMA(normal DMA from Qsys) in arria 10 devkit. The DMA goes into busy state after the transfer is initiated but doesn't come out ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

Hello,

We faced similar type of issue few years back. At that time, we read following from DMA's user guide: "in burst mode, the length of a transaction must not be longer than the configured maximum burst size. otherwise, the transaction must be performed as multiple transactions." This means, if you set your burst size to 1024, then transaction size must not be greater than that. In your case, if you set burst size to 1024, then I think you should not face any issue when transfer length is less or equal to 1024. But if transfer size is greater than that (which is the case in all examples you have mentioned so far), you should see some unexpected behavior.

Regards,

Bhaumik