stm32adc多通道采集

在STM32中，ADC可以实现多通道采集，以下是一个基本的多通道采集代码示例：

#include "stm32f4xx.h"

#define ADC1_DR_ADDRESS ((uint32_t)0x4001204C)

uint16_t ADC_Values[3]; //存储采集结果的数组

void ADC_Configuration(void)
{
    ADC_InitTypeDef ADC_InitStructure;
    GPIO_InitTypeDef GPIO_InitStructure;
    DMA_InitTypeDef DMA_InitStructure;

    //使能ADC时钟和DMA时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);

    //ADC采样通道对应的GPIO口配置
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    GPIO_Init(GPIOC, &GPIO_InitStructure);

    //DMA配置
    DMA_InitStructure.DMA_Channel = DMA_Channel_0;
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_ADDRESS;
    DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&ADC_Values;
    DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
    DMA_InitStructure.DMA_BufferSize = 3;
    DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
    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_FIFOMode = DMA_FIFOMode_Disable;
    DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
    DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
    DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
    DMA_Init(DMA2_Stream0, &DMA_InitStructure);

    //ADC配置
    ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
    ADC_InitStructure.ADC_ScanConvMode = ENABLE;
    ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
    ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
    ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
    ADC_InitStructure.ADC_NbrOfConversion = 3;
    ADC_Init(ADC1, &ADC_InitStructure);

    //配置ADC采样通道
    ADC_RegularChannelConfig(ADC1, ADC_Channel_10, 1, ADC_SampleTime_84Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_11, 2, ADC_SampleTime_84Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_12, 3, ADC_SampleTime_84Cycles);

    //使能DMA
    ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
    DMA_Cmd(DMA2_Stream0, ENABLE);

    //使能ADC
    ADC_Cmd(ADC1, ENABLE);

    //校准ADC
    ADC_MultiModeDMARequestAfterLastTransferCmd(ENABLE);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_10, 1, ADC_SampleTime_84Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_11, 2, ADC_SampleTime_84Cycles);
    ADC_RegularChannelConfig(ADC1, ADC_Channel_12, 3, ADC_SampleTime_84Cycles);
    ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
    ADC_DMACmd(ADC1, ENABLE);
    ADC_SoftwareStartConv(ADC1);
}

int main(void)
{
    ADC_Configuration();
    while (1)
    {
        //等待DMA采集完成
        while (DMA_GetFlagStatus(DMA2_Stream0, DMA_FLAG_TCIF0) == RESET);
        DMA_ClearFlag(DMA2_Stream0, DMA_FLAG_TCIF0);

        //输出采集结果
        printf("ADC1_CH10: %d\r\n", ADC_Values[0]);
        printf("ADC1_CH11: %d\r\n", ADC_Values[1]);
        printf("ADC1_CH12: %d\r\n", ADC_Values[2]);
    }
}

上述代码中，我们使用了DMA来实现ADC的多通道采集。首先配置ADC和DMA，然后在主函数中等待DMA采集完成，最后输出采集结果。在这里，我们采集了PA0、PA1和PA2三个通道的数据，并存储在ADC_Values数组中。

需要注意的是，为了避免多通道采集时出现的采样顺序错误问题，我们在ADC配置的时候使用了扫描模式，并且配置了采样顺序。同时，我们还需要配置DMA的循环模式，以保证DMA可以不间断地采集数据。