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Altera_Forum
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15 years ago

SGDMA too slow with PCIe core

Hello, I am seeting up the Altera contents for a frame grabber poject. I use a Cyclone IV GX 22 with a 4x PCIe interface. For this purpose the PCIe hard IP core is applied in the SOPC builder ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Hi,

Thanks for the advices!

The root cause turned out now. The problem was that the SGDMA input was set to 32 bit while the output was 64 bit because of the input of PCI Express core. Because of this the SGDMA requested only two 32 bit words, tied them and sent to the PCIe without any burst mode.

I have changed the input to 64 bit wide and it is much faster now. Unbelivable fast!

I will move to Qsys to get a more stable system and better timing results.

Regards,

Istvan