DMAC Demos

Single Block

Allocate a free channel
```
ch_num = GDMA_ChnlAlloc(gdma.index, (IRQ_FUN) Dma_memcpy_int, (u32)(&gdma), 3);
```
This function also includes the following operation:
- Register IRQ handler if using interrupt mode
- Enable NVIC interrupt
- Register the DMAC channel to use

Configure the interrupt type

PGDMA_InitTypeDef->GDMA_IsrType = (TransferType | ErrType);

Configure interrupt handling function

Clear the pending interrupt in the interrupt processing function.
```
GDMA_ClearINT(0, PGDMA_InitTypeDef->GDMA_ChNum);
```

Configure transfer settings

PGDMA_InitTypeDef->GDMA_SrcMsize   = MsizeEight;
PGDMA_InitTypeDef->GDMA_SrcDataWidth = TrWidthFourBytes;
PGDMA_InitTypeDef->GDMA_DstMsize = MsizeEight;
PGDMA_InitTypeDef->GDMA_DstDataWidth = TrWidthFourBytes;
PGDMA_InitTypeDef->GDMA_BlockSize = DMA_CPY_LEN >> 2;
PGDMA_InitTypeDef->GDMA_DstInc = IncType; // if dst type is peripheral:no change
PGDMA_InitTypeDef->GDMA_SrcInc = IncType; // if src type is peripheral:no change

Configure hardware handshake interface if slave is peripheral

PGDMA_InitTypeDef->GDMA_SrcHandshakeInterface= GDMA_HANDSHAKE_INTERFACE_AUDIO_RX;

or

PGDMA_InitTypeDef->GDMA_DstHandshakeInterface = GDMA_HANDSHAKE_INTERFACE_AUDIO_TX;

Configure the transfer address

PGDMA_InitTypeDef->GDMA_SrcAddr = (u32)BDSrcTest;
PGDMA_InitTypeDef->GDMA_DstAddr = (u32)BDDstTest;

Program DMAC index, DMAC channel, data width, msize, transfer direction, address increment mode, hardware handshake interface, reload control, interrupt type, block size, multi-block configuration and the source and destination address using the GDMA_Init() function.
```
GDMA_Init(gdma.index, gdma.ch_num, PGDMA_InitTypeDef);
```
Clean and invalidate Cache
```
DCache_CleanInvalidate();
```

Enable DMAC channel

GDMA_Cmd(gdma.index, gdma.ch_num, ENABLE);

Multi-block

This example is SRC auto reload, compared with single block, multi-block is different in Step 2 to Step 4.

Allocate a free channel
```
ch_num = GDMA_ChnlAlloc(gdma.index, (IRQ_FUN) Dma_memcpy_int, (u32)(&gdma), 3);
```
This function also includes the following operation:
- Register IRQ handler if use interrupt mode
- Enable NVIC interrupt
- Register the DMAC channel to use

Configure the interrupt type

PGDMA_InitTypeDef->GDMA_IsrType = (BlockType | TransferType | ErrType);

Configure interrupt handling function

Clear the interrupt.

GDMA_ClearINT(0, PGDMA_InitTypeDef->GDMA_ChNum);

Clear the auto reload mode before the last block starts.

GDMA_ChCleanAutoReload(0, PGDMA_InitTypeDef->GDMA_ChNum, CLEAN_RELOAD_SRC);

Configure transfer settings

PGDMA_InitTypeDef->GDMA_SrcMsize   = MsizeEight;
PGDMA_InitTypeDef->GDMA_SrcDataWidth = TrWidthFourBytes;
PGDMA_InitTypeDef->GDMA_DstMsize = MsizeEight;
PGDMA_InitTypeDef->GDMA_DstDataWidth = TrWidthFourBytes;
PGDMA_InitTypeDef->GDMA_BlockSize = DMA_CPY_LEN >> 2;
PGDMA_InitTypeDef->GDMA_DstInc = IncType; // If DST type is peripheral: no change
PGDMA_InitTypeDef->GDMA_SrcInc = IncType; // If SRC type is peripheral: no change
PGDMA_InitTypeDef->GDMA_ReloadSrc = 1;
PGDMA_InitTypeDef->GDMA_ReloadDst = 0;

Configure hardware handshake interface if slave is peripheral.

PGDMA_InitTypeDef->GDMA_SrcHandshakeInterface= GDMA_HANDSHAKE_INTERFACE_AUDIO_RX;

or

PGDMA_InitTypeDef->GDMA_DstHandshakeInterface = GDMA_HANDSHAKE_INTERFACE_AUDIO_TX;

Configure the transfer address

PGDMA_InitTypeDef->GDMA_SrcAddr = (u32)BDSrcTest;
PGDMA_InitTypeDef->GDMA_DstAddr = (u32)BDDstTest;

Program DMAC index, DMAC channel, data width, msize, transfer direction, address increment mode, hardware handshake interface, reload control, interrupt type, block size, multi-block configuration and the source and destination address using the GDMA_Init() function.
```
GDMA_Init(gdma.index, gdma.ch_num, PGDMA_InitTypeDef);
```
Clean and invalidate Cache
```
DCache_CleanInvalidate();
```

Enable DMAC channel

GDMA_Cmd(gdma.index, gdma.ch_num, ENABLE);