STM32F405 ADC采样

newphj 提问时间：2017-1-9 16:22 /

STM32F405RGT6_64PIN的芯片,PA0-PA7用做ADC1 DMA采样引脚，引脚全部接VCC的时候，只有PA4，PA5得到的数据是4095.。剩下的引脚都只有3000左右。使用STM32Cube生成工程也是这样。不知道是那里问题。STM32F407，用STM32Cube生成ADC1采样工程都是正确的。是我那里没有设置好吗。

代码：
   #define ADC1_DR_ADDRESS    ((uint32_t)0x4001204C)
   uint16_t uhADCxConvertedValue[CHANNELNUM] = {0};

      ADC_InitTypeDef    ADC_InitStructure;
ADC_CommonInitTypeDef ADC_CommonInitStructure;
DMA_InitTypeDef    DMA_InitStructure;
GPIO_InitTypeDef    GPIO_InitStructure;
/* Enable ADCx, DMA and GPIO clocks ****************************************/
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2, ENABLE);
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
/* DMA2 Stream0 channel2 configuration **************************************/
DMA_InitStructure.DMA_Channel = DMA_Channel_0;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)ADC1_DR_ADDRESS;
DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)&uhADCxConvertedValue[0];
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
DMA_InitStructure.DMA_BufferSize = CHANNELNUM;
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_FIFOMode = DMA_FIFOMode_Disable;
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;
DMA_Init(DMA2_Stream0, &DMA_InitStructure);
DMA_Cmd(DMA2_Stream0, ENABLE);
/* Configure ADC3 Channel7 pin as analog input ******************************/
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed= GPIO_Medium_Speed;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* ADC Common Init **********************************************************/
ADC_CommonInitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_CommonInitStructure.ADC_Prescaler = ADC_Prescaler_Div8;
ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1;
ADC_CommonInitStructure.ADC_TwoSamplingDelay = ADC_TwoSamplingDelay_10Cycles;
ADC_CommonInit(&ADC_CommonInitStructure);
/* ADC3 Init ****************************************************************/
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ScanConvMode = ENABLE;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_None;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConvEdge_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfConversion = 8;
ADC_Init(ADC1, &ADC_InitStructure);
/* ADC3 regular channel7 configuration **************************************/
ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 2, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 3, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 4, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 5, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_5, 6, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_6, 7, ADC_SampleTime_56Cycles);
ADC_RegularChannelConfig(ADC1, ADC_Channel_7, 8, ADC_SampleTime_56Cycles);
/* Enable DMA request after last transfer (Single-ADC mode) */
ADC_DMARequestAfterLastTransferCmd(ADC1, ENABLE);
/* Enable ADC3 DMA */
ADC_DMACmd(ADC1, ENABLE);
/* Enable ADC3 */
ADC_Cmd(ADC1,ENABLE);
/* Start ADC Software Conversion */
ADC_SoftwareStartConv(ADC1);