Does anyone has a simple Nios DMA example?

Hi, now I hope use the Nios DMA to improve my own circuit's performance.

But I meet some problems. I have seen the handbook from altera website,

but the example they provided need some extra devices (like a VGA card).

Therefore, I need a very simple example to teach me how to use Nios DMA to transfer data,

like an add accumulator or some simple circuit.

If someone have it, please send to the email address (pipiwau@yahoo.com.tw).

Thank you very much.