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Altera_Forum's avatar
Altera_Forum
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15 years ago

Want to determine Altera Development Board SOPC Recipe equivalent?

hi, I have a Altera GX Development board. I am using Quartus 9.1 SP2. I am writing my own Windows driver which needs to do DMA transfers from the device memory to PC Host. I won'...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Hmmmmm...it looks like the Altera Demo is doing DMA transfers onboard, and not to PC Host, thus I can't get comparable figures.

I can get 30MB/sec going from onboard DDR2 to PC Host now.

I've played with the various bursting options as follows:

* I set 8 beats in the DDR2 memory settings

* 8 wide read burst signal and 8 wide write burst signal in the SGDMA engine settings

* data width 64 for Data and Error Widths (but I don't think that applies when you are bursting....only for non-bursts)

* use the High Performance II Memory controller, with Local Maximum Burst count 8.

The descriptors are put into the onboard DDR2 memory. I am NOT enabling bursting on read descriptor read master. Maybe I can get an improvement by either enabling bursting, or put the descriptors into onchip memory ? but it would be very small won't it ?

...however, I would like to find out what the theoritcal/pratical maximum I could achieve with the SGDMA...between onboard DDR2 and PC Host.....anyone have any ideas?