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STM32G070的ADC多通道采集

1. 非DMA方式采集

1.1 关于ADC扫描定序（scan sequencer）

2. DMA方式采集

本文讲述基于STM32G070进行ADC多通道采集，并分别介绍非DMA方式和DMA方式。

1. 非DMA方式采集

ADC初始化代码如下（使用STM32CubeMx自动生成），配置了3个通道：

static void MX_ADC1_Init(void)

{

  /* USER CODE BEGIN ADC1_Init 0 */

  /* USER CODE END ADC1_Init 0 */

  ADC_ChannelConfTypeDef sConfig = {0};

  /* USER CODE BEGIN ADC1_Init 1 */

  /* USER CODE END ADC1_Init 1 */

  /** 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.DataAlign = ADC_DATAALIGN_RIGHT;

  hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;

  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;

  hadc1.Init.LowPowerAutoWait = DISABLE;

  hadc1.Init.LowPowerAutoPowerOff = DISABLE;

  hadc1.Init.ContinuousConvMode = DISABLE;

  hadc1.Init.NbrOfConversion = 3;

  hadc1.Init.DiscontinuousConvMode = ENABLE;

  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;

  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;

  hadc1.Init.DMAContinuousRequests = DISABLE;

  hadc1.Init.Overrun = ADC_OVR_DATA_PRESERVED;

  hadc1.Init.SamplingTimeCommon1 = ADC_SAMPLETIME_1CYCLE_5;

  hadc1.Init.SamplingTimeCommon2 = ADC_SAMPLETIME_1CYCLE_5;

  hadc1.Init.OversamplingMode = DISABLE;

  hadc1.Init.TriggerFrequencyMode = ADC_TRIGGER_FREQ_HIGH;

  if (HAL_ADC_Init(&hadc1) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_4;

  sConfig.Rank = ADC_REGULAR_RANK_1;

  sConfig.SamplingTime = ADC_SAMPLINGTIME_COMMON_1;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_5;

  sConfig.Rank = ADC_REGULAR_RANK_2;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_9;

  sConfig.Rank = ADC_REGULAR_RANK_3;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /* USER CODE BEGIN ADC1_Init 2 */

  /* USER CODE END ADC1_Init 2 */

}

获取ADC数据

// 校准

HAL_ADCEx_Calibration_Start(&hadc1);

for (idx = 0; idx < 3; idx++)

{

    HAL_ADC_Start(&hadc1);

    HAL_ADC_PollForConversion(&hadc1, 50);

    /* Check if the continous conversion is finished */

    if(HAL_IS_BIT_SET(HAL_ADC_GetState(&hadc1), HAL_ADC_STATE_REG_EOC))

    {

        /* Get the converted value */

        AD_Value[idx] = HAL_ADC_GetValue(&hadc1);

    }

}

HAL_ADC_Stop(&hadc1);

1.1 关于ADC扫描定序（scan sequencer）

ADC scan sequencer can be used in two different modes. 配置ADC多通道采集时，对于各个通道的采集顺序有两种方式：

Sequencer fully configurable (The order in which the channels are scanned is independent from the channel number)

采用这种方式时，ADC的通道扫描顺序将和channel number不再相关，如1中代码，就采用了这种方式

//扫描方式：ADC_SCAN_ENABLE

hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;

//...

sConfig.Channel = ADC_CHANNEL_5;

sConfig.Rank = ADC_REGULAR_RANK_2;

if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

{

    Error_Handler();

}

sConfig.Channel = ADC_CHANNEL_6;

sConfig.Rank = ADC_REGULAR_RANK_1;

if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

{

    Error_Handler();

}

如果按照如上代码配置，在采集时，将先采集channel 6，再采集channel 5。但是使用该方式时，需要注意Only channel 0 to channel 14 can be selected in this sequence。即channel 15/16/17/18无法使用该方式，如果需要使用channel 15-18，则可以使用下面第二种扫描方式。

Sequencer not fully configurable (The order in which the channels are scanned is defined by the channel number)

这种方式比较好理解，就是按照channel number的大小，按顺序进行扫描，配置代码如下：

// 扫描方式：ADC_SCAN_SEQ_FIXED

hadc1.Init.ScanConvMode = ADC_SCAN_SEQ_FIXED;

sConfig.Channel = ADC_CHANNEL_16;

sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

{

    Error_Handler();

}

2. DMA方式采集

直接上代码：

static void MX_ADC1_Init(void)

{

  /* USER CODE BEGIN ADC1_Init 0 */

  /* USER CODE END ADC1_Init 0 */

  ADC_ChannelConfTypeDef sConfig = {0};

  /* USER CODE BEGIN ADC1_Init 1 */

  /* USER CODE END ADC1_Init 1 */

  /** Configure the global features of the ADC (Clock, Resolution, Data Alignment and number of conversion)

  */

  hadc1.Instance = ADC1;

  hadc1.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV1;

  hadc1.Init.Resolution = ADC_RESOLUTION_12B;

  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;

  hadc1.Init.ScanConvMode = ADC_SCAN_SEQ_FIXED;

  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;

  hadc1.Init.LowPowerAutoWait = DISABLE;

  hadc1.Init.LowPowerAutoPowerOff = DISABLE;

  hadc1.Init.ContinuousConvMode = ENABLE;

  hadc1.Init.DiscontinuousConvMode = DISABLE;

  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;

  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;

  hadc1.Init.DMAContinuousRequests = ENABLE;

  hadc1.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN;

  hadc1.Init.SamplingTimeCommon1 = ADC_SAMPLETIME_12CYCLES_5;

  hadc1.Init.OversamplingMode = DISABLE;

  hadc1.Init.TriggerFrequencyMode = ADC_TRIGGER_FREQ_HIGH;

  if (HAL_ADC_Init(&hadc1) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_4;

  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_5;

  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_9;

  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_10;

  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /** Configure Regular Channel

  */

  sConfig.Channel = ADC_CHANNEL_16;

  sConfig.Rank = ADC_RANK_CHANNEL_NUMBER;

  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)

  {

    Error_Handler();

  }

  /* USER CODE BEGIN ADC1_Init 2 */

  /* USER CODE END ADC1_Init 2 */

}

static void MX_DMA_Init(void)

{

  /* DMA controller clock enable */

  __HAL_RCC_DMA1_CLK_ENABLE();

  /* DMA interrupt init */

  /* DMA1_Channel1_IRQn interrupt configuration */

  HAL_NVIC_SetPriority(DMA1_Channel1_IRQn, 0, 0);

  HAL_NVIC_EnableIRQ(DMA1_Channel1_IRQn);

}

void HAL_ADC_MspInit(ADC_HandleTypeDef* hadc)

{

  GPIO_InitTypeDef GPIO_InitStruct = {0};

  if(hadc->Instance==ADC1)

  {

  /* USER CODE BEGIN ADC1_MspInit 0 */

  /* USER CODE END ADC1_MspInit 0 */

    /* Peripheral clock enable */

    __HAL_RCC_ADC_CLK_ENABLE();

    __HAL_RCC_GPIOA_CLK_ENABLE();

    __HAL_RCC_GPIOB_CLK_ENABLE();

    /**ADC1 GPIO Configuration

    PA4     ------> ADC1_IN4

    PA5     ------> ADC1_IN5

    PB1     ------> ADC1_IN9

    PB2     ------> ADC1_IN10

    PB12     ------> ADC1_IN16

    */

    GPIO_InitStruct.Pin = GPIO_PIN_4|GPIO_PIN_5;

    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;

    GPIO_InitStruct.Pull = GPIO_NOPULL;

    HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_InitStruct.Pin = GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_12;

    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;

    GPIO_InitStruct.Pull = GPIO_NOPULL;

    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    /* ADC1 DMA Init */

    /* ADC1 Init */

    hdma_adc1.Instance = DMA1_Channel1;

    hdma_adc1.Init.Request = DMA_REQUEST_ADC1;

    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;

    if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)

    {

      Error_Handler();

    }

    __HAL_LINKDMA(hadc,DMA_Handle,hdma_adc1);

  /* USER CODE BEGIN ADC1_MspInit 1 */

  /* USER CODE END ADC1_MspInit 1 */

  }

}

初始化完成后，即可使用：

//开始ADC转换

HAL_ADCEx_Calibration_Start(&hadc1);

HAL_ADC_Start_DMA(&hadc1, (uint32_t *)&AD_Value_Buffer, AD_DMA_BUFF_LENGTH);

注：AD_Value_Buffer为事先定义好的数组，长度为AD_DMA_BUFF_LENGTH

接下来，无需CPU参与，DMA将会把ADC采集到数据搬运至AD_Value_Buffer的地址中，当长度达到AD_DMA_BUFF_LENGTH时，将从头开始，此时会覆盖数据。

原文链接：https://blog.csdn.net/crazy_kismet/article/details/105550170