本帖最后由 qq344269956 于 2014-12-10 11:18 编辑
各位大神,请表我看一下吧。我使用DMA+ADC 对一路信号进行采集,DMA和ADC配置为:
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
/* Enable ADC1 and GPIOC clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);
//配置GPIO
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11 | GPIO_Pin_12;//PA11-->DM PA12-->DP
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
//配置ADC 和 DMA
/* DMA channel1 configuration ----------------------------------------------*/
DMA_DeInit(DMA1_Channel1);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC1_DR_Address;
DMA_InitStructure.DMA_MemoryBaseAddr = (u32)&ADCConvertedValue;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 1;
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);
/* ADC1 configuration ------------------------------------------------------*/
ADC_InitStructure.ADC_Mode = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanConvMode = DISABLE ;
ADC_InitStructure.ADC_ContinuousConvMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_None;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NbrOfChannel = 1;
ADC_Init(ADC1, &ADC_InitStructure);
/* ADC1 regular channel8 configuration */
ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 1, ADC_SampleTime_1Cycles5);
/* Enable ADC1 DMA */
ADC_DMACmd(ADC1, ENABLE);
/* Enable ADC1 */
ADC_Cmd(ADC1, ENABLE);
/* 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);
IO口设置为:
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AIN;
GPIO_Init(GPIOB, &GPIO_InitStructure);
直接使用固定变量对DMA过行测试,发现没有问题。
单步调试ADC时,采集值也是一样的,。。。。。
采集开始后,查询ADC的采集值一直为0x850~0x750之间,接高电平和接地都一样,这是怎么回来?
换用别的IO口进行采集也是类似情况。
我的电路是直接对串联电阻中间电压过行采集。 |