Strange DMA Transfer

Altera_Forum · ‎03-10-2005

Hello, everyone. I'm the one of engineers to struggle with NIOS2.

I want to use DMA in 16bit mode.

The following data is transfered from main memory(SDRAM in my kit) to peripheral.

DATA: 0000h 01E0h D33Ah ... (continued)

Next image describes well.

But, the first data(0000h) appears during 4 cycles and next data(01E0h) appears two times again.

I cann't understand that situation.

I tried to use DMA-transfer from main memory(SDRAM in my kit) to the same(SDRAM in my kit) in 16bit mode.

And I experienced the same case. I think, DMA may have problem.

At the end of Develpment of my product, I have been much anxious about the problem.

Please, help me, Nios Users and ALTERA !

Good luck to every Nios Users.

Altera_Forum · ‎03-16-2005

I just tried the experiment of transferring data to and from SDRAM in 16-bit mode (for a 32-bit SDRAM) and it seems to work fine.

Can you post your code which does the 16-bit SDRAM transfer?