stm32f407定时器触发adc采样HAL库代码

下面是使用HAL库编写的在STM32F407上使用定时器触发ADC采样的示例代码。

首先需要配置ADC和定时器的初始化参数。

ADC_HandleTypeDef hadc1;
TIM_HandleTypeDef htim2;

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_DIV4;
  hadc1.Init.Resolution = ADC_RESOLUTION_12B;
  hadc1.Init.ScanConvMode = DISABLE;
  hadc1.Init.ContinuousConvMode = ENABLE;
  hadc1.Init.DiscontinuousConvMode = DISABLE;
  hadc1.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_RISING;
  hadc1.Init.ExternalTrigConv = ADC_EXTERNALTRIGCONV_T2_TRGO;
  hadc1.Init.DataAlign = ADC_DATAALIGN_RIGHT;
  hadc1.Init.NbrOfConversion = 1;
  hadc1.Init.DMAContinuousRequests = DISABLE;
  hadc1.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  if (HAL_ADC_Init(&hadc1) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure for the selected ADC regular channel its corresponding rank in the sequencer and its sample time.
  */
  sConfig.Channel = ADC_CHANNEL_0;
  sConfig.Rank = 1;
  sConfig.SamplingTime = ADC_SAMPLETIME_3CYCLES;
  if (HAL_ADC_ConfigChannel(&hadc1, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }

}

void MX_TIM2_Init(void)
{
  TIM_MasterConfigTypeDef sMasterConfig;

  htim2.Instance = TIM2;
  htim2.Init.Prescaler = 8399;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = 1999;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
  {
    Error_Handler();
  }

  sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
}

在主函数中，开启定时器和ADC：

int main(void)
{
  HAL_Init();

  SystemClock_Config();

  MX_GPIO_Init();
  MX_TIM2_Init();
  MX_ADC1_Init();

  HAL_TIM_Base_Start(&htim2);
  HAL_ADC_Start(&hadc1);

  while (1)
  {
    if (HAL_ADC_PollForConversion(&hadc1, 1000) == HAL_OK)
    {
      uint32_t adc_value = HAL_ADC_GetValue(&hadc1);
      printf("ADC value: %ld\n", adc_value);
    }
  }
}

在这个示例中，定时器的时钟频率为84MHz / (8399 + 1) = 10 kHz，定时器的周期为(1999 + 1) / 10 kHz = 200ms，ADC的采样时间为3个时钟周期，因此每200ms会触发一次ADC采样。

需要注意的是，这个示例中使用了轮询模式进行ADC采样，也可以使用DMA模式进行采样以提高效率。