Newbie Question: Access DPR outside SOPC Builder

Hi andreg,

I see wrong things in your code. Check if they are only copy and paste errors or actual code errors:

- in alt_dma_rxchan_prepare(), the 4th parameter should be dma_done, namely the pointer to function to be called upon dma completion

- you wait dma completion testing a rx_done variable, but you actually set the other variable dma_complete when dma completes

- are you sure the tx_data and rx_buffer addresses you provide match those of memories connected to tx/rx dma: you should use system.h defines instead of numeric values.

I have a design similar to your one and it works perfectly.

I tried to use your same code (with the above corrections) and the dma performs correctly.

The only differences being:

- dma width is 16bits

- tx dma is from external sram connected to sopc tristate bus

- rx dma is to the main sdram and not a separate onchip memory

(I don't think you need that descriptor memory; you are not using a sgdma module)

Final note: pay attention to define rx_done as volatile, otherwise compiler may assume the while loop never ends.

Regards

Cris