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Altera_Forum
Honored Contributor
Honored ContributorMax throughput of SOPC DMA?
Hello, Currently I have a system with DMA transfers and DDR2 SDRAM (and a lot of other stuff). I'm using the normal SOPC builder DMA controller. I run the system on 100 MHz, the DDR2 SDRAM run...
Altera_ForumHonored Contributor
Honored ContributorI don't use bursting at the moment no, because I haven't enabled that. When I tried to use bursting a while back it didn't seem to work, but I can try that again. Since it was most likely due a software fault.
The max amount I can burst at one time is 1024 words (if the DDR2 can handle that) . So that indeed means I would have to set up 8192 DMA transfers if I wanted to transfer 32 megabyte. I did try using two seperate on-chip memories though for communicating with the Serial RapidIO core (again non bursting): [On-chip TX_data] -> Serial RapidIO Core loopback -> [On-chip RX_data] and I get a whopping speed of 8.2203 megabyte/second. With the following set-up: [DDR memory_1] -> Serial RapidIO Core loopback -> [DDR memory_1] I got a speed of 4,9936 megabyte/second Maybe I should use bursting for the entire system then (since the Serial RapidIO Core supports it). Since you are saying these kinds of speed aren't normal.
