DMA (Direct Memory access)

Question

How do i write a code for Direct memory access(DMA) using function calls in c sharp inplace of Programmed input output(PIO) to transfer multiple number of data?

 

I have already created an application of PIO to transfer block of data but i need to implement the same with respect to DMA for multiple transfer of data. please do suggest me with this as

 

how can i write the function calls like, wd_transfer and few more.

 

Thank you in advance

Kavya