STM32F103 ADC 单片机3V供电

只看该作者 · 2017-10-25 15:12

代码：
#define ADC0_DR_Address ((u32)0x4001244C)

__IO u16 ADC_ConvertedValue;

/*????2é?ùí¨μà???ú ê1?üGPIOê±?ó    éè??ADC2é?ùPA0???úD?o?*/
void ADC0_GPIO_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;       //GPIOéè???a?￡?aê?è?
  GPIO_Init(GPIOA, &GPIO_InitStructure);
}

/*????ADC0μ?1¤×÷?￡ê??aMDA?￡ê?  */
void ADC0_Mode_Config(void)
{
  DMA_InitTypeDef DMA_InitStructure;
  ADC_InitTypeDef ADC_InitStructure;
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); //ê1?üMDA1ê±?ó
/* DMA channel1 configuration */
  DMA_DeInit(DMA1_Channel1);  //???¨DMAí¨μà
  DMA_InitStructure.DMA_PeripheralBaseAddr = ADC0_DR_Address;//éè??DMAíaéèμ??·
  DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&ADC_ConvertedValue; //éè??DMA?ú′?μ??·￡?ADC×a???á1??±?ó·?è???μ??·
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //íaéè?aéè???aêy?Y′?ê?μ?à′?′
  DMA_InitStructure.DMA_BufferSize = 1; //DMA?o3???éè???a1￡?
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Disable;
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
  DMA_Init(DMA1_Channel1, &DMA_InitStructure);

  /* Enable DMA channel1 */
  DMA_Cmd(DMA1_Channel1, ENABLE);  //ê1?üDMAí¨μà

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE); //ê1?üADC1ê±?ó

  /* ADC1 configuration */
  ADC_InitStructure.ADC_Mode = ADC_Mode_Independent; //ê1ó??àá￠?￡ê?￡?é¨?è?￡ê?
  ADC_InitStructure.ADC_ScanConvMode = ENABLE;
  ADC_InitStructure.ADC_ContinuousConvMode = ENABLE; //?TDèía?ó′￥·￠?÷
  ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None; //ê1ó?êy?Yóò????
  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
  ADC_InitStructure.ADC_NbrOfChannel = 1;  // ??óD1??×a??í¨μà
  ADC_Init(ADC1, &ADC_InitStructure);

  /* ADC1 regular channel11 configuration */
  ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_55Cycles5); //í¨μà12é?ù?ü?ú55.5??ê±?ó?ü?ú

  /* Enable ADC1 DMA */
  ADC_DMACmd(ADC1, ENABLE);    //ê1?üADCμ?DMA

  /* Enable ADC1 */
  ADC_Cmd(ADC1, ENABLE); //ê1?üADC1

  /* Enable ADC1 reset calibaration register */
  ADC_ResetCalibration(ADC1);
  /* Check the end of ADC1 reset calibration register */
  while(ADC_GetResetCalibrationStatus(ADC1));

  /* Start ADC1 calibaration */
  ADC_StartCalibration(ADC1);
  /* Check the end of ADC1 calibration */
  while(ADC_GetCalibrationStatus(ADC1));

  /* Start ADC1 Software Conversion */
  ADC_SoftwareStartConvCmd(ADC1, ENABLE);  //?aê?×a??
}

/*3?ê??ˉADC1 */
void ADC0_Init(void)
{
ADC0_GPIO_Config();
ADC0_Mode_Config();
}

AD_value  = 3300000/4096*ADC_ConvertedValue/1000;

目前我用了3V LDO给STM32F103供电，如果外部接入3.3V电压给单片机，AD采集可以正常执行，采集的结果也正确，但用3V供电AD也工作，但采集的数据不对了。