STM32 DMA學(xué)習

一個(gè)簡(jiǎn)單的例子 transfer a word data buffer from FLASH memory to embedded SRAM memory.
在V3.1.2庫的位置
STM32F10x_StdPeriph_Lib_V3.1.2ProjectSTM32F10x_StdPeriph_ExamplesDMAFLASH_RAM

/* DMA1 channel6 configuration */
DMA_DeInit(DMA1_Channel6);
//peripheral base address
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)SRC_Const_Buffer;
//memory base address
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)DST_Buffer;
//數據傳輸方向 Peripheral is source
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
//緩沖區大小 Number of data to be transferred (0 up to 65535).數據傳輸數目
DMA_InitStructure.DMA_BufferSize = BufferSize;
// the Peripheral address register is incremented
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Enable;
//the memory address register is incremented
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
//the Peripheral data width
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
//the DMAy Channelx will be used in memory-to-memory transfer
//DMA通道的操作可以在沒(méi)有外設請求的情況下進(jìn)行，這種操作就是存儲器到存儲器模式。
DMA_InitStructure.DMA_M2M = DMA_M2M_Enable;
DMA_Init(DMA1_Channel6, &DMA_InitStructure);

/* Enable DMA1 Channel6 Transfer Complete interrupt */
DMA_ITConfig(DMA1_Channel6, DMA_IT_TC, ENABLE);


/* Enable DMA1 Channel6 transfer */
DMA_Cmd(DMA1_Channel6, ENABLE);
=======================================================================

外設的DMA請求映像


要使DMA與外設建立有效連接，這不是DMA自身的事情，是各個(gè)外設的事情，每個(gè)外設都有 一個(gè)

xxx_DMACmd(XXXx,Enable )函數，如果使DMA與ADC建立有效聯(lián)系，就使用 ADC_DMACmd

(ADC1,Enable); （這里我啟用了ADC中的ADC1模塊）。

/* DMA1 channel1 configuration ----------------------------------------------*/
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&AD_Value;
//u16 AD_Value[2]; 不加&應該也可以 數組名 代表地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 2; //############## 改了
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //############## 改了
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);

/* Enable DMA1 channel 1 */
DMA_Cmd(DMA1_Channel1, ENABLE);

/* ADC1 configuration------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = ENABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 2; //############## 改了
ADC_Init(ADC1, &ADC_InitStructure);
//內部溫度傳感器 添加這一句
/* Enable the temperature sensor and vref internal channel */
ADC_TempSensorVrefintCmd(ENABLE);
//############## 改了

//################ Channel 10(電位器)
ADC_RegularChannelConfig(ADC1, ADC_Channel_10, 1, ADC_SampleTime_13Cycles5);
//###### 內部溫度傳感器 Channel 16 ###################
ADC_RegularChannelConfig(ADC1, ADC_Channel_16, 2, ADC_SampleTime_55Cycles5);

/* Enable ADC1 DMA */使能ADC1的DMA請求映像
ADC_DMACmd(ADC1, ENABLE);

/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE);

/* Enable ADC1 reset calibaration register */ //使用之前一定要校準
ADC_ResetCalibration(ADC1);
/* Check the end of ADC1 reset calibration register */
while(ADC_GetResetCalibrationStatus(ADC1));

/* Start ADC1 calibaration */
ADC_StartCalibration(ADC1);
/* Check the end of ADC1 calibration */
while(ADC_GetCalibrationStatus(ADC1));

/* Start ADC1 Software Conversion */
ADC_SoftwareStartConvCmd(ADC1, ENABLE);