[原创] 【NUCLEO-L452RE测评】+简易数字电压表

借助STM32L452内部的ADC，再配置一个OLED屏就可形成一个简单的数字电压表，其显示效果如图1至图3所示。

A/D采集所使用的通道为ADC_CHANNEL_9，占用的引脚为PA4。

图1 悬空状态下的采集值

图2 连接GND的测量值

图3 连接VDD的测量值

实现该显示效果的主程序为：

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  BSP_LED_Init(LED2);
  AdcHandle.Instance = ADCx;
  if (HAL_ADC_DeInit(&AdcHandle) != HAL_OK)
  {
    Error_Handler();
  }
  AdcHandle.Init.ClockPrescaler        = ADC_CLOCK_ASYNC_DIV1;
  AdcHandle.Init.Resolution            = ADC_RESOLUTION_12B;
  AdcHandle.Init.DataAlign             = ADC_DATAALIGN_RIGHT;
  AdcHandle.Init.ScanConvMode          = DISABLE;
  AdcHandle.Init.EOCSelection          = ADC_EOC_SINGLE_CONV;
  AdcHandle.Init.LowPowerAutoWait      = DISABLE;
  AdcHandle.Init.ContinuousConvMode    = ENABLE;
  AdcHandle.Init.NbrOfConversion       = 1;
  AdcHandle.Init.DiscontinuousConvMode = DISABLE;
  AdcHandle.Init.NbrOfDiscConversion   = 1;
  AdcHandle.Init.ExternalTrigConv      = ADC_SOFTWARE_START;
  AdcHandle.Init.ExternalTrigConvEdge  = ADC_EXTERNALTRIGCONVEDGE_NONE;
  AdcHandle.Init.DMAContinuousRequests = DISABLE;
  AdcHandle.Init.Overrun               = ADC_OVR_DATA_OVERWRITTEN;
  AdcHandle.Init.OversamplingMode      = ENABLE;
  AdcHandle.Init.Oversampling.Ratio                 = OVERSAMPLING_RATIO;
  AdcHandle.Init.Oversampling.RightBitShift         = RIGHTBITSHIFT;
  AdcHandle.Init.Oversampling.TriggeredMode         = TRIGGEREDMODE;
  AdcHandle.Init.Oversampling.OversamplingStopReset = OVERSAMPLINGSTOPRESET;
  if (HAL_ADC_Init(&AdcHandle) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_ADCEx_Calibration_Start(&AdcHandle, ADC_SINGLE_ENDED) != HAL_OK)
  {
    Error_Handler();
  }
  sConfig.Channel      = ADCx_CHANNEL;
  sConfig.Rank         = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLETIME_6CYCLES_5;
  sConfig.SingleDiff   = ADC_SINGLE_ENDED;
  sConfig.OffsetNumber = ADC_OFFSET_NONE;
  sConfig.Offset = 0;
  if (HAL_ADC_ConfigChannel(&AdcHandle, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_ADC_Start(&AdcHandle) != HAL_OK)
  {
    Error_Handler();
  }
  APP_OLED_Init();
  OLED_Init();
  OLED_Clear();
  OLED_ShowString(8,0,"STM32L452RE",16);
  OLED_ShowString(8,2,"OLED & ADC ",16);
  OLED_ShowCHinese(80,0,0);
  OLED_ShowCHinese(96,0,1);
  OLED_ShowCHinese(112,0,2);
  OLED_ShowString(60,6,"mV",16);
  while (1)
  {   
    if (HAL_ADC_PollForConversion(&AdcHandle, 10) != HAL_OK)
    {
      Error_Handler();
    }
    uwConvertedValue = HAL_ADC_GetValue(&AdcHandle);
    OLED_ShowNum(10,4,uwConvertedValue,6,16);
    uwInputVoltage = uwConvertedValue * 3300;
    uwInputVoltage = uwInputVoltage / 0xFFF0;
    OLED_ShowNum(10,6,uwInputVoltage,5,16);
    HAL_Delay(500);
  }
}

谢谢分享！