ADC过采样

只看该作者 · 2021-1-11 18:59

ADC_over_sampling

/*************************************************/
This example describes how to use the ADC1 and DMA to transfer continuously  converted data from ADC1 to memory.
The ADC1 is configured to convert continuously channel14.
Each time an end of conversion occurs the DMA transfers, in circular mode, the converted data from ADC1 DR register to the ADCConvertedValue variable.
The ADC1 clock is set to 18 MHz.

/*ADC_OVSR：过采样率，取值：2,4,8,16,32,64,128,256*/
#define ADC_OVSR 256

/*ADC_shift：ADC结果右移，取值：0~8*/
#define ADC_shift  4

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
ADC_InitType ADC_InitStructure;
DMA_InitType DMA_InitStructure;
__IO uint16_t ADCConvertedValue[256] = {0,};
__IO uint32_t ADCConvertedValue_16 = 0;
/* Private function prototypes -----------------------------------------------*/
void RCC_Configuration(void);
void GPIO_Configuration(void);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{

uint16_t i,j ;

/* System clocks configuration */
RCC_Configuration();

/* GPIO configuration ------------------------------------------------------*/
GPIO_Configuration();

/* DMA1 channel1 configuration ----------------------------------------------*/
DMA_Reset(DMA1_Channel1);
DMA_DefaultInitParaConfig(&DMA_InitStructure);
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&ADC1->RDOR;
DMA_InitStructure.DMA_MemoryBaseAddr       = (uint32_t)&ADCConvertedValue;
DMA_InitStructure.DMA_Direction          = DMA_DIR_PERIPHERALSRC;
DMA_InitStructure.DMA_BufferSize          = ADC_OVSR;
DMA_InitStructure.DMA_PeripheralInc       = DMA_PERIPHERALINC_DISABLE;
DMA_InitStructure.DMA_MemoryInc          = DMA_MEMORYINC_ENABLE;
DMA_InitStructure.DMA_PeripheralDataWidth = DMA_PERIPHERALDATAWIDTH_HALFWORD;
DMA_InitStructure.DMA_MemoryDataWidth    = DMA_MEMORYDATAWIDTH_HALFWORD;
DMA_InitStructure.DMA_Mode                = DMA_MODE_CIRCULAR;
DMA_InitStructure.DMA_Priority             = DMA_PRIORITY_HIGH;
DMA_InitStructure.DMA_MTOM                = DMA_MEMTOMEM_DISABLE;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
/* Enable DMA1 channel1 */
DMA_ChannelEnable(DMA1_Channel1, ENABLE);

/* ADC1 configuration ------------------------------------------------------*/
ADC_StructInit(&ADC_InitStructure);
ADC_InitStructure.ADC_Mode             = ADC_Mode_Independent;
ADC_InitStructure.ADC_ScanMode       = ENABLE;
ADC_InitStructure.ADC_ContinuousMode = ENABLE;
ADC_InitStructure.ADC_ExternalTrig    = ADC_ExternalTrig_None;
ADC_InitStructure.ADC_DataAlign       = ADC_DataAlign_Right;
ADC_InitStructure.ADC_NumOfChannel    = 1;
ADC_Init(ADC1, &ADC_InitStructure);

/* ADC1 regular channels configuration */
ADC_RegularChannelConfig(ADC1, ADC_Channel_0, 1, ADC_SampleTime_1_5);

/* Enable ADC1 DMA */
ADC_DMACtrl(ADC1, ENABLE);

/* Enable ADC1 */
ADC_Ctrl(ADC1, ENABLE);

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

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

/* Start ADC1 Software Conversion */
ADC_SoftwareStartConvCtrl(ADC1, ENABLE);

while (1)
{
while( DMA_GetITStatus(DMA1_INT_TC1) == SET)
{
ADCConvertedValue_16 = 0;
for(i=0;i<ADC_OVSR;i++)
ADCConvertedValue_16 += ADCConvertedValue;//过采样求和
ADCConvertedValue_16 = (ADCConvertedValue_16>>ADC_shift)&0xFFFF;//求位移&取16位结果截断
DMA_ClearITPendingBit(DMA1_INT_TC1);
}

}
}

/**
  * @brief  Configures the different system clocks.
  * @param  None
  * @retval None
  */
void RCC_Configuration(void)
{
/* ADCCLK = PCLK2/4 */
RCC_ADCCLKConfig(RCC_APB2CLK_Div4);

/* Enable peripheral clocks ------------------------------------------------*/
/* Enable DMA1 clocks */
RCC_AHBPeriphClockCmd(RCC_AHBPERIPH_DMA1, ENABLE);

/* Enable ADC1 and GPIOA clocks */
RCC_APB2PeriphClockCmd(RCC_APB2PERIPH_ADC1 , ENABLE);
RCC_AHBPeriphClockCmd(RCC_AHBPERIPH_GPIOA , ENABLE);
}

/**
  * @brief  Configures the different GPIO ports.
  * @param  None
  * @retval None
  */
void GPIO_Configuration(void)
{
GPIO_InitType GPIO_InitStructure;

/* Configure PA0 (ADC Channel0) as analog input -------------------------*/
GPIO_StructInit(&GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pins = GPIO_Pins_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_Init(GPIOA, &GPIO_InitStructure);
}