最近需要用到两个ADC对电压电流进行同步采样，看了一下STM32的ADC介绍，发现STM32最多有3个独立ADC，有在双AD模式下可以进行同步测量，正好满足我的要求。参考官方给的例子在结合自己的需要写了一下配置程序。
程序1 根据官方例子写的：
#include"adc.h"
__IO uint32_t ADC_DualConvertedValueTab[ADC_BufferLength];
void ADC1_2_Init(void)
{
ADC_InitTypeDef ADC_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
RCC_ADCCLKConfig(RCC_PCLK2_Div4);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_ADC2 | RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
DMA_DeInit(DMA1_Channel1); //DMA通道1恢复到默认状态
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_Address; //设置数据来源地址
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)ADC_DualConvertedValueTab; //设置copy目标地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //设置copy方向
DMA_InitStructure.DMA_BufferSize = 16; //设置数组大小
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //数据来源不变
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //数据保存的数组地址自增
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; //DMA操作字长 32位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; //DMA操作字长 32位
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; //普通的DMA操作模式：当DMA操作转移够 数组大小 //所限定的数据总量后，则不再进行DMA操作
DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA优先级
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //关闭mTM
DMA_Init(DMA1_Channel1, &DMA_InitStructure); //使能dma
/* Enable DMA1 Channel1 */
DMA_Cmd(DMA1_Channel1, ENABLE);
/* ADC1 configuration ------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult; //ADC1同步规则组模式
ADC_InitStructure.ADC_ScanConvMode = ENABLE; //启动扫描
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //连续转换
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; //无外部触发
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //结果右对齐
ADC_InitStructure.ADC_NbrOfChannel = 1; //转换通道数2
ADC_Init(ADC1, &ADC_InitStructure); //配置ADC1
/* ADC1 regular channels configuration */
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_239Cycles5); //通道配置
/* Enable ADC1 DMA */
ADC_DMACmd(ADC1, ENABLE);
/* ADC2 configuration ------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult; //ADC2同步规则组模式
ADC_InitStructure.ADC_ScanConvMode = ENABLE; //启动扫描
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //连续转换
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; //无外部触发
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //结果右对齐
ADC_InitStructure.ADC_NbrOfChannel = 1; //转换通道数
ADC_Init(ADC2, &ADC_InitStructure); //配置ADC2
/* ADC2 regular channels configuration */
ADC_RegularChannelConfig(ADC2, ADC_Channel_4, 1, ADC_SampleTime_239Cycles5); //通道配置
/* Enable ADC2 external trigger conversion */
ADC_ExternalTrigConvCmd(ADC2, ENABLE); //使能ADC2的外部触发模式
/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE); //使能ADC1
/* Enable Vrefint channel17 */
// ADC_TempSensorVrefintCmd(ENABLE); // 使能温度传感器内部参考电压通道
/* Enable ADC1 reset calibration register */
ADC_ResetCalibration(ADC1); //ADC1的校准
/* Check the end of ADC1 reset calibration register */
while(ADC_GetResetCalibrationStatus(ADC1));
/* Start ADC1 calibration */
ADC_StartCalibration(ADC1);
/* Check the end of ADC1 calibration */
while(ADC_GetCalibrationStatus(ADC1));
/* Enable ADC2 */
ADC_Cmd(ADC2, ENABLE); //使能ADC2
/* Enable ADC2 reset calibration register */
ADC_ResetCalibration(ADC2); //ADC2的校准
/* Check the end of ADC2 reset calibration register */
while(ADC_GetResetCalibrationStatus(ADC2));
/* Start ADC2 calibration */
ADC_StartCalibration(ADC2);
/* Check the end of ADC2 calibration */
while(ADC_GetCalibrationStatus(ADC2));
/* Start ADC1 Software Conversion */ //软件启动ADC1，开始转换
ADC_SoftwareStartConvCmd(ADC1, ENABLE);
/* Test on DMA1 channel1 transfer complete flag */ //等待一组DMA存储转换完成
while(!DMA_GetFlagStatus(DMA1_FLAG_TC1));
/* Clear DMA1 channel1 transfer complete flag */
DMA_ClearFlag(DMA1_FLAG_TC1);
DMA_Done = 1;
}
两个ADC采出来的数据存在32位数组ADC_DualConvertedValueTab[ADC_BufferLength]中，其中ADC1对应低16位，ADC2对应高16位。可通过以下程序读出：
uint16_t adc1_val[1000];
uint16_t adc2_val[1000];
for(i=0;i<1000;i++)
{
adc1_val[i] = ADC_DualConvertedValueTab[i];
adc2_val[i] = ADC_DualConvertedValueTab[i]>>16;
}
最后再附上自己写的用TIM3触发采样的程序，可以自己调用来设置采样率。
程序2：
void ADC1_2_Config(u16 SampleFreq,u16 DMA_BufferSizer)
{
ADC_InitTypeDef ADC_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_ADCCLKConfig(RCC_PCLK2_Div2);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 | RCC_APB2Periph_ADC2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1 | GPIO_Pin_4;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
//定时器3控制采样率
TIM_TimeBaseStructure.TIM_Prescaler= 0;
TIM_TimeBaseStructure.TIM_CounterMode= TIM_CounterMode_Up;
TIM_TimeBaseStructure.TIM_Period= 72000000 / SampleFreq - 1;
TIM_TimeBaseStructure.TIM_ClockDivision= 0;
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit( TIM3, &TIM_TimeBaseStructure);
TIM_SelectOutputTrigger( TIM3, TIM_TRGOSource_Update );
TIM_ARRPreloadConfig(TIM3,ENABLE);
TIM_Cmd( TIM3, ENABLE );
DMA_DeInit(DMA1_Channel1); //DMA通道1恢复到默认状态
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_Address; //设置数据来源地址
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)ADC_DualConvertedValueTab; //设置copy目标地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //设置copy方向
DMA_InitStructure.DMA_BufferSize = ADC_BufferLength; //设置数组大小
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; //数据来源不变
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; //数据保存的数组地址自增
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word; //DMA操作字长 32位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word; //DMA操作字长 32位
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; //普通的DMA操作模式：当DMA操作转移够 数组大小 //所限定的数据总量后，则不再进行DMA操作
DMA_InitStructure.DMA_Priority = DMA_Priority_High; //DMA优先级
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable; //关闭mTM
DMA_Init(DMA1_Channel1, &DMA_InitStructure); //使能dma
/* Enable DMA1 Channel1 */
DMA_Cmd(DMA1_Channel1, ENABLE);
/* DMA Transfer Complete Interrupt enable */
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn; //通道
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1; //占先级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //响应级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //启动
NVIC_Init(&NVIC_InitStructure); //初始化
DMA_ITConfig(DMA1_Channel1,DMA_IT_TC,ENABLE);
/* ADC1 configuration ------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult; //ADC1同步规则组模式
ADC_InitStructure.ADC_ScanConvMode = ENABLE; //启动扫描
ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; //连续转换
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T3_TRGO; //无外部触发
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //结果右对齐
ADC_InitStructure.ADC_NbrOfChannel = 1; //转换通道数2
ADC_Init(ADC1, &ADC_InitStructure); //配置ADC1
/* ADC1 regular channels configuration */
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_28Cycles5); //通道配置
/* Enable ADC1 DMA */
ADC_DMACmd(ADC1, ENABLE);
/* ADC2 configuration ------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult; //ADC2同步规则组模式
ADC_InitStructure.ADC_ScanConvMode = ENABLE; //启动扫描
ADC_InitStructure.ADC_ContinuousConvMode = DISABLE; //连续转换
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; //无外部触发
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //结果右对齐
ADC_InitStructure.ADC_NbrOfChannel = 1; //转换通道数
ADC_Init(ADC2, &ADC_InitStructure); //配置ADC2
/* ADC2 regular channels configuration */
ADC_RegularChannelConfig(ADC2, ADC_Channel_4, 1, ADC_SampleTime_28Cycles5); //通道配置
/* Enable ADC2 external trigger conversion */
ADC_ExternalTrigConvCmd(ADC2, ENABLE); //使能ADC2的外部触发模式
/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE); //使能ADC1
/* Enable Vrefint channel17 */
// ADC_TempSensorVrefintCmd(ENABLE); // 使能温度传感器内部参考电压通道
/* Enable ADC1 reset calibration register */
ADC_ResetCalibration(ADC1); //ADC1的校准
/* Check the end of ADC1 reset calibration register */
while(ADC_GetResetCalibrationStatus(ADC1));
/* Start ADC1 calibration */
ADC_StartCalibration(ADC1);
/* Check the end of ADC1 calibration */
while(ADC_GetCalibrationStatus(ADC1));
/* Enable ADC2 */
ADC_Cmd(ADC2, ENABLE); //使能ADC2
/* Enable ADC2 reset calibration register */
ADC_ResetCalibration(ADC2); //ADC2的校准
/* Check the end of ADC2 reset calibration register */
while(ADC_GetResetCalibrationStatus(ADC2));
/* Start ADC2 calibration */
ADC_StartCalibration(ADC2);
/* Check the end of ADC2 calibration */
while(ADC_GetCalibrationStatus(ADC2));
/* Start ADC1 Software Conversion */ //软件启动ADC1，开始转换
ADC_SoftwareStartConvCmd(ADC1, ENABLE);
// while(!DMA_GetFlagStatus(DMA1_FLAG_TC1));
// /* Clear DMA1 channel1 transfer complete flag */
// DMA_ClearFlag(DMA1_FLAG_TC1);
// DMA_Done = 1;
}
void DMA1_Channel1_IRQHandler(void)
{
if(DMA_GetITStatus(DMA1_IT_TC1) != RESET)
{
DMA_ClearITPendingBit(DMA1_IT_TC1);
DMA_ITConfig(DMA1_Channel1,DMA_IT_TC,DISABLE);
ADC_Cmd(ADC1,DISABLE);
ADC_Cmd(ADC2,DISABLE);
DMA_Done =1;
}
}
调用方式：ADC1_2_Config(5120,512);
可以用作FFT分析前的采样。