ADC采集，数据只有0和4095，是什么问题？

只看该作者 · 2017-11-10 09:23

STM32F103VET6，ADC+DMA采集，电压是16.8V电池电阻6分压的电压
接上电池AD数据就是4095，不接就是0，IO口量过电压是2点多伏

程序在RET6上正常使用，到VET6上由IO口由C口换到了PB1，仔细检查过很多遍了
估计可能是什么原因？帮我指点下方向我再检查

1万 · 2017-11-10 10:25

程序的问题，再检查下你的程序。

只看该作者 · 2017-11-10 10:57

ADC+DMA 我也遇到了这个现象读回来的数不是0就是4095或者1023,2047这几种。

只看该作者 · 2017-11-10 11:17

不爱说话发表于 2017-11-10 10:57
ADC+DMA 我也遇到了这个现象读回来的数不是0就是4095或者1023,2047这几种。

后来怎么解决的？

只看该作者 · 2017-11-10 11:31

初始化程序很简单，用的引脚是PA0，PA1和PB1

void  Adc_Init(void)
{
ADC_InitTypeDef ADC_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA |RCC_APB2Periph_GPIOB |RCC_APB2Periph_ADC1,ENABLE );
RCC_ADCCLKConfig(RCC_PCLK2_Div6);


GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOB, &GPIO_InitStructure);

ADC_DeInit(ADC1);

ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = ENABLE;//DISABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 5;
ADC_Init(ADC1, &ADC_InitStructure);

    ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_239Cycles5 );
   ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_239Cycles5 );
   ADC_RegularChannelConfig(ADC1, ADC_Channel_9, 3, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_16, 4, ADC_SampleTime_239Cycles5 );
ADC_RegularChannelConfig(ADC1, ADC_Channel_17, 5, ADC_SampleTime_239Cycles5 );

ADC_Cmd(ADC1, ENABLE);
ADC_DMACmd(ADC1, ENABLE);

ADC_TempSensorVrefintCmd(ENABLE);
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));

ADC_SoftwareStartConvCmd(ADC1, ENABLE);
}

void DMA_Config(void)
{
DMA_InitTypeDef DMA_InitStructure;
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);

DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&AD_Value;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;

DMA_InitStructure.DMA_BufferSize = 5;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
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);

DMA_Cmd(DMA1_Channel1, ENABLE);
}