STM32ADC多通道DMA传输

ADC多通道采集是在ADC单通道DMA传输的基础上写的，代码如下：

volatile u16 adcconverdata[2]={0,0};

static void ADC_GPIO_Config(void)

{

  GPIO_InitTypeDef  GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);

GPIO_InitStructure.GPIO_Pin=GPIO_Pin_1|GPIO_Pin_2;//添加PA2的GPIO初始化代码

GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AIN;

GPIO_Init(GPIOA, &GPIO_InitStructure);

}

static void ADC_Mode_Config(void)

{

  ADC_InitTypeDef ADC_InitStructure;

  DMA_InitTypeDef DMA_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1,ENABLE);

RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1,ENABLE);

DMA_DeInit(DMA1_Channel1);

DMA_InitStructure.DMA_PeripheralBaseAddr=(uint32_t)&ADC1->DR;

DMA_InitStructure.DMA_MemoryBaseAddr=(uint32_t)adcconverdata;//由于采集的是多通道的数据，必须定义数组来存放数据，而数组的名字就是数组的首地址。所以不能这么写(uint32_t)&adcconverdata;

DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;

DMA_InitStructure.DMA_BufferSize=2;   //由于是两个通道，这里改成2

DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //开启内存地址自增

DMA_InitStructure.DMA_PeripheralInc =DMA_PeripheralInc_Disable ;

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_Medium;

DMA_InitStructure.DMA_M2M=DMA_M2M_Disable;

DMA_Init(DMA1_Channel1,&DMA_InitStructure);

DMA_Cmd(DMA1_Channel1,ENABLE);

ADC_DeInit(ADC1);

ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;

ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;

ADC_InitStructure.ADC_ScanConvMode=ENABLE; //开启扫描模式

ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;

ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;

ADC_InitStructure.ADC_NbrOfChannel=2;  //通道书为2

ADC_Init(ADC1,&ADC_InitStructure);

RCC_ADCCLKConfig(RCC_PCLK2_Div8); 

ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_239Cycles5);

ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 2, ADC_SampleTime_239Cycles5);//定义通道的转换顺序

ADC_DMACmd(ADC1,ENABLE);

  ADC_Cmd(ADC1,ENABLE);

ADC_ResetCalibration(ADC1);

while(ADC_GetResetCalibrationStatus(ADC1));

ADC_StartCalibration(ADC1);

while(ADC_GetCalibrationStatus(ADC1));

ADC_SoftwareStartConvCmd(ADC1,ENABLE);

}

void ADC_InitConfig(void)

{

  ADC_GPIO_Config();

ADC_Mode_Config();

}

上述代码中红色部分为需要修改或者添加的代码，此部分代码我已经注释，比较容易理解

下面附主函数的代码

extern volatile u16 adcconverdata[2]; 

 int main(void) 

 {

 float m[2]; 

 delay_init();     

 NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

uart_init(115200); 

ADC_InitConfig(); 

 while(1)

 { 

 printf("adcconverdata[0]=%d \r\n",adcconverdata[0]); 

 printf("adcconverdata[1]=%d \r\n",adcconverdata[1]); delay_ms(500); 

 }

 }

代码在while循环里直接打印出采集到的数据。上面代码我使用的是PA1和PA2作为采集通道。