STM32F407 DMA采集多通道ADC

STM32F407和STM32F103在HAL库使用的时候有较大的差别，同时407取消掉了ADC校准，在使用DMA进行多通道采集时需要打开DMA连续请求：hadc1.Init.DMAContinuousRequests = ENABLE;否则DMA传输的数组里面就只会有第一次传输的数据，再也不会增加了。
同时在实验过程中发现407的ADC精度貌似不是很准确，采样率越高，偏差越大。受到（http://www.openedv.com/forum.php?mod=viewthread&tid=51312）的启发，自己也进行了一点小小的实验。
ADC1的通道3在 ADCCLK=10.8MHz（8分频）的情况下，对通道3进行接地处理，数字稳定在0-1之间；对通道3接入高电平3.3v,数字稳定在4092；在2分频的情况下，ADCCLK=42MHz（2分频），对通道3进行接地处理，数字稳定在2-3之间；对通道3接入高电平3.3v,数字稳定在4092；

自己分析出现以上情况，可能是参考电压有问题或者本身板子的设计有问题，干扰太大。但是也没深究，希望对精度有更高要求的同志能进行较为深入的研究，给大家指条明路。

并且，在引脚悬空的情况下会出现数值在1040-1060之间的数值跳动，因此输入管脚请不要悬空处理！！！！！！！！！

下面贴一下ADC.C的信息双通道进行DMA处理，第一通道接PA3，接受光敏电阻的信息，第二通道是单片机内部的温度通道。

#include "adc.h"

#include "gpio.h"
#include "dma.h"

/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

ADC_HandleTypeDef hadc1;
DMA_HandleTypeDef hdma_adc1;

/* ADC1 init function */
void MX_ADC1_Init(void)
{
  ADC_ChannelConfTypeDef sConfig;

    /**Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion) 
    */
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV2;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.ScanConvMode = ENABLE;
  hadc1.Init.ContinuousConvMode = ENABLE;
  hadc1.Init.DiscontinuousConvMode = DISABLE;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.NbrOfConversion = 2;
  hadc1.Init.DMAContinuousRequests = ENABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

    /**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time. 
    */
  sConfig.Channel = ADC_CHANNEL_3;
  sConfig.Rank = 1;
  sConfig.SamplingTime = ADC_SAMPLETIME_480CYCLES;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

    /**Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time. 
    */
  sConfig.Channel = ADC_CHANNEL_TEMPSENSOR;
  sConfig.Rank = 2;
  sConfig.SamplingTime = ADC_SAMPLETIME_112CYCLES;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

}

void HAL_ADC_MspInit(ADC_HandleTypeDef* adcHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct;
  if(adcHandle->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspInit 0 */

  /* USER CODE END ADC1_MspInit 0 */
    /* ADC1 clock enable */
    __HAL_RCC_ADC1_CLK_ENABLE();
  
    /**ADC1 GPIO Configuration    
    PA3     ------> ADC1_IN3 
    */
    GPIO_InitStruct.Pin = GPIO_PIN_3;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    /* ADC1 DMA Init */
    /* ADC1 Init */
    hdma_adc1.Instance = DMA2_Stream0;
    hdma_adc1.Init.Channel = DMA_CHANNEL_0;
    hdma_adc1.Init.Direction = DMA_PERIPH_TO_MEMORY;
    hdma_adc1.Init.PeriphInc = DMA_PINC_DISABLE;
    hdma_adc1.Init.MemInc = DMA_MINC_ENABLE;
    hdma_adc1.Init.PeriphDataAlignment = DMA_PDATAALIGN_WORD;
    hdma_adc1.Init.MemDataAlignment = DMA_MDATAALIGN_WORD;
    hdma_adc1.Init.Mode = DMA_CIRCULAR;
    hdma_adc1.Init.Priority = DMA_PRIORITY_LOW;
    hdma_adc1.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
    if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)
    {
      _Error_Handler(__FILE__, __LINE__);
    }

    __HAL_LINKDMA(adcHandle,DMA_Handle,hdma_adc1);

  /* USER CODE BEGIN ADC1_MspInit 1 */

  /* USER CODE END ADC1_MspInit 1 */
  }
}

void HAL_ADC_MspDeInit(ADC_HandleTypeDef* adcHandle)
{

  if(adcHandle->Instance==ADC1)
  {
  /* USER CODE BEGIN ADC1_MspDeInit 0 */

  /* USER CODE END ADC1_MspDeInit 0 */
    /* Peripheral clock disable */
    __HAL_RCC_ADC1_CLK_DISABLE();
  
    /**ADC1 GPIO Configuration    
    PA3     ------> ADC1_IN3 
    */
    HAL_GPIO_DeInit(GPIOA, GPIO_PIN_3);

    /* ADC1 DMA DeInit */
    HAL_DMA_DeInit(adcHandle->DMA_Handle);
  /* USER CODE BEGIN ADC1_MspDeInit 1 */

  /* USER CODE END ADC1_MspDeInit 1 */
  }
}

最后奉上源代码。点击打开链接

STM32F407 DMA采集多通道ADC

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