[嵌入式]STM32F2XX使用DMA实现MTOM(M2M/MEMORY TO MEMORY)初始化函数代码

需要注意，stm32f2xx系列只有DMA2可以实现mtom

mtom其实就是flash到sram的过程

void DMA_M2M_Init(void)
{
	DMA_InitTypeDef DMA_InitStruct;

	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
	DMA_InitStruct.DMA_Channel = DMA_Channel_0;
	DMA_InitStruct.DMA_PeripheralBaseAddr = (u32)aSRC_Const_Buffer;
	DMA_InitStruct.DMA_Memory0BaseAddr = (u32)aDST_Buffer;
	DMA_InitStruct.DMA_DIR = DMA_DIR_MemoryToMemory;
	DMA_InitStruct.DMA_BufferSize = BUFFER_SIZE;
	DMA_InitStruct.DMA_PeripheralInc = DMA_PeripheralInc_Enable;
	DMA_InitStruct.DMA_MemoryInc = DMA_MemoryInc_Enable;
	DMA_InitStruct.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
	DMA_InitStruct.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
	DMA_InitStruct.DMA_Mode = DMA_Mode_Normal;
	DMA_InitStruct.DMA_Priority = DMA_Priority_High;
	DMA_InitStruct.DMA_FIFOMode = DMA_FIFOMode_Enable;
	DMA_InitStruct.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull;
	DMA_InitStruct.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
	DMA_InitStruct.DMA_MemoryBurst = DMA_MemoryBurst_Single;
	DMA_Init(DMA2_Stream0, &DMA_InitStruct);

	DMA_ClearFlag(DMA2_Stream0, DMA_FLAG_TCIF0);
	DMA_Cmd(DMA2_Stream0, ENABLE);
}

其中定义源数组和目标数组如下，源数组使用const定义

// 要发送的数据大小
#define BUFFER_SIZE     32

/* 定义aSRC_Const_Buffer数组作为DMA传输数据源
 * const关键字将aSRC_Const_Buffer数组变量定义为常量类型
 * 表示数据存储在内部的FLASH中
 */
const uint32_t aSRC_Const_Buffer[BUFFER_SIZE]= {
                                    0x01020304,0x05060708,0x090A0B0C,0x0D0E0F10,
                                    0x11121314,0x15161718,0x191A1B1C,0x1D1E1F20,
                                    0x21222324,0x25262728,0x292A2B2C,0x2D2E2F30,
                                    0x31323334,0x35363738,0x393A3B3C,0x3D3E3F40,
                                    0x41424344,0x45464748,0x494A4B4C,0x4D4E4F50,
                                    0x51525354,0x55565758,0x595A5B5C,0x5D5E5F60,
                                    0x61626364,0x65666768,0x696A6B6C,0x6D6E6F70,
                                    0x71727374,0x75767778,0x797A7B7C,0x7D7E7F80};
/* 定义DMA传输目标存储器
 * 存储在内部的SRAM中																		
 */
uint32_t aDST_Buffer[BUFFER_SIZE];