HAL库ADC多通道采样

在HAL库中，可以使用HAL_ADC_MultiModeStart_DMA函数实现ADC多通道采样。以下是C代码示例：

// 定义ADC_HandleTypeDef句柄和DMA_HandleTypeDef句柄
ADC_HandleTypeDef hadc1;
DMA_HandleTypeDef hdma_adc1;

// 定义ADC转换结果数组
uint32_t adc_values[4];

// 配置ADC1和DMA
void adc_init(void)
{
  // 配置ADC1的通道和采样时间
  ADC_ChannelConfTypeDef sConfig = {0};
  hadc1.Instance = ADC1;
  hadc1.Init.ClockPrescaler = ADC_CLOCK_SYNC_PCLK_DIV4;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.ScanConvMode = ADC_SCAN_ENABLE;
  hadc1.Init.ContinuousConvMode = ENABLE;
  hadc1.Init.DiscontinuousConvMode = DISABLE;
  hadc1.Init.NbrOfDiscConversion = 0;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc1.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.NbrOfConversion = 4;
  hadc1.Init.DMAContinuousRequests = ENABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SEQ_CONV;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.Channel = ADC_CHANNEL_0;
  sConfig.Rank = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLETIME_28CYCLES;
  sConfig.SingleDiff = ADC_SINGLE_ENDED;
  sConfig.OffsetNumber = ADC_OFFSET_NONE;
  sConfig.Offset = 0;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.Channel = ADC_CHANNEL_1;
  sConfig.Rank = ADC_REGULAR_RANK_2;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.Channel = ADC_CHANNEL_2;
  sConfig.Rank = ADC_REGULAR_RANK_3;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.Channel = ADC_CHANNEL_3;
  sConfig.Rank = ADC_REGULAR_RANK_4;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }

  // 配置DMA
  hdma_adc1.Instance = DMA1_Channel1;
  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_HIGH;
  if (HAL_DMA_Init(&hdma_adc1) != HAL_OK)
  {
    Error_Handler();
  }
  __HAL_LINKDMA(&hadc1, DMA_Handle, hdma_adc1);

  // 启动DMA
  HAL_DMA_Start(&hdma_adc1, (uint32_t)&hadc1.Instance->DR, (uint32_t)adc_values, 4);
}

// 启动ADC转换
void adc_start(void)
{
  HAL_ADC_Start_DMA(&hadc1, (uint32_t*)adc_values, 4);
}

// 获取ADC转换结果
uint32_t adc_get_value(uint8_t channel)
{
  return adc_values[channel];
}

以上代码中，我们通过HAL_ADC_MultiModeStart_DMA函数启动了ADC多通道采样，并将转换结果存储在adc_values数组中。需要注意的是，由于使用了DMA，因此需要在adc_init函数中配置DMA，并在adc_start函数中启动DMA。另外，通过adc_get_value函数可以获取指定通道的转换结果。