Usage Code

desc.ul_source_addr = (uint32_t) g_dma_buf[0];
desc.ul_destination_addr = (uint32_t) g_dma_buf[1];

• Set the buffer transfer size to DMA_BUF_SIZE

• Set the source transfer width to 32-bit

• Set the destination transfer width to 32-bit

  desc.ul_ctrlA = DMAC_CTRLA_BTSIZE(DMA_BUF_SIZE) |
          DMAC_CTRLA_SRC_WIDTH_WORD |
          DMAC_CTRLA_DST_WIDTH_WORD;
  

  Configure DMA CTRLB:

• Disable source buffer descriptor fetch

• Disable destination buffer descriptor Fetch

• Enable memory-to-memory transfer

• Increment the source address

• Increment the destination address

  desc.ul_ctrlB = DMAC_CTRLB_SRC_DSCR_FETCH_DISABLE |
          DMAC_CTRLB_DST_DSCR_FETCH_DISABLE |
          DMAC_CTRLB_FC_MEM2MEM_DMA_FC |
          DMAC_CTRLB_SRC_INCR_INCREMENTING |
          DMAC_CTRLB_DST_INCR_INCREMENTING;
  

  Initialize the DMA transfer:

  desc.ul_descriptor_addr = 0;
  dmac_channel_single_buf_transfer_init(DMAC, DMA_CH, &desc);
  

  Start the DMA transfer:

  dmac_channel_enable(DMAC, DMA_CH);
  

  Finally, poll for the DMA transfer to complete:

  while (!dmac_channel_is_transfer_done(DMAC, DMA_CH)) {
  }