适用于嵌入式ADC RC低通滤波

只看该作者 · 2025-5-24 20:22

 

#define                ADC_SMPILE_NUM                4

#define                ADC_CHANNEL_NUM                6

uint16_t adc1Value[ADC_SMPILE_NUM][ADC_CHANNEL_NUM];

 

// Filtered measurement variables

uint32_t  adcFilterSum[ADC_SMPILE_NUM];

uint16_t  adcFilteredAdcVal[ADC_SMPILE_NUM];

 

uint16_t _ADC_GetSingleReading(uint8_t adcChannel)

{

        uint32_t adcval =adc1Value[0][adcChannel]+

                                        adc1Value[1][adcChannel]+

                                        adc1Value[2][adcChannel]+

                                        adc1Value[3][adcChannel];

        return         adcval>>2;

}

 

void hdl_adcInit(void){

 

        GPIO_InitTypeDef GPIO_InitStruct;

        RCC_AHBPeriphClockCmd(RCC_AHBENR_GPIOA, ENABLE); 

        RCC_AHBPeriphClockCmd(RCC_AHBENR_GPIOB, ENABLE);

 

        GPIO_StructInit(&GPIO_InitStruct);

        GPIO_InitStruct.GPIO_Pin  =  GPIO_Pin_1|GPIO_Pin_4/*|GPIO_Pin_5*/|GPIO_Pin_6|GPIO_Pin_7;

        GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

        GPIO_InitStruct.GPIO_Mode =GPIO_Mode_AIN;

        GPIO_Init(GPIOA, &GPIO_InitStruct);

        GPIO_InitStruct.GPIO_Pin  =  GPIO_Pin_0|GPIO_Pin_1;

        GPIO_Init(GPIOB, &GPIO_InitStruct);

        

        DMA_InitTypeDef DMA_InitStruct;

        RCC_AHBPeriphClockCmd(RCC_AHBENR_DMA1, ENABLE);

        DMA_DeInit(DMA1_Channel1);

        DMA_StructInit(&DMA_InitStruct);

        //DMA transfer peripheral address

        DMA_InitStruct.DMA_PeripheralBaseAddr = (u32) & (ADC1->DR);

        //DMA transfer memory address

        DMA_InitStruct.DMA_MemoryBaseAddr = (u32)adc1Value;

        //DMA transfer direction from peripheral to memory

        DMA_InitStruct.DMA_DIR = DMA_DIR_PeripheralSRC;

        //DMA cache size

        DMA_InitStruct.DMA_BufferSize = ADC_SMPILE_NUM*ADC_CHANNEL_NUM;

        //After receiving the data, the peripheral address is forbidden to move backward

        DMA_InitStruct.DMA_PeripheralInc = DMA_PeripheralInc_Disable;

        //After receiving the data, the memory address is shifted backward

        DMA_InitStruct.DMA_MemoryInc = DMA_MemoryInc_Enable;

        //Define the peripheral data width to 16 bits

        DMA_InitStruct.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;

        //Define the memory data width to 16 bits

        DMA_InitStruct.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;

        //Cycle conversion mode

        DMA_InitStruct.DMA_Mode = DMA_Mode_Circular;

        //DMA priority is high

        DMA_InitStruct.DMA_Priority = DMA_Priority_High;

        //M2M mode is disabled

        DMA_InitStruct.DMA_M2M = DMA_M2M_Disable;

        DMA_InitStruct.DMA_Auto_reload = DMA_Auto_Reload_Disable;

        DMA_Init(DMA1_Channel1, &DMA_InitStruct);

        DMA_Cmd(DMA1_Channel1, ENABLE);

                

        ADC_DeInit(ADC1);

        ADC_InitTypeDef  ADC_InitStruct;

        ADC_StructInit(&ADC_InitStruct);

        //Enable ADC clock

        RCC_APB2PeriphClockCmd(RCC_APB2ENR_ADC1, ENABLE);

        ADC_InitStruct.ADC_Resolution = ADC_Resolution_12b;

        //ADC prescale factor

        ADC_InitStruct.ADC_PRESCARE = ADC_PCLK2_PRESCARE_2;

        //Set ADC mode to continuous conversion mode

        ADC_InitStruct.ADC_Mode = ADC_Mode_Continue;

        //AD data right-justified

        ADC_InitStruct.ADC_DataAlign = ADC_DataAlign_Right;

    ADC_InitStruct.ADC_ExternalTrigConv = ADC1_ExternalTrigConv_T2_TRIG;

        ADC_Init(ADC1, &ADC_InitStruct);

 

        //Enable the channel

        ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 0, ADC_Samctl_8_5);//1

        ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 0, ADC_Samctl_8_5);//2

        ADC_RegularChannelConfig(ADC1, ADC_Channel_6, 0, ADC_Samctl_8_5);//3

        ADC_RegularChannelConfig(ADC1, ADC_Channel_7, 0, ADC_Samctl_8_5);//4

        ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 0, ADC_Samctl_8_5);//5

        ADC_RegularChannelConfig(ADC1, ADC_Channel_9, 0, ADC_Samctl_8_5);//6

  //Enable ADCDMA

        ADC_DMACmd(ADC1, ENABLE);

        //Enable AD conversion

        ADC_Cmd(ADC1, ENABLE);

        ADC_ExternalTrigConvConfig(ADC1,ADC1_ExternalTrigConv_T1_CC1);

        ADC1->CR |=(1<<24)|(3<<19);//下降沿触发 ,512 个延时周期

        ADC_ExternalTrigConvCmd(ADC1, ENABLE);

}

 

// adc samp 

void TIM3_init(void){

   RCC_APB1PeriphClockCmd(RCC_APB1ENR_TIM3, ENABLE);

        uint32_t arr =72000000L /100 -1;//100hz adc采样率

        TIM3->CR1 =(1<<7)|(1<<2);

        TIM3->PSC =0;

        TIM3->ARR =arr;

        TIM3->DIER =(1<<0);

                

        NVIC_InitTypeDef NVIC_InitStruct;

    NVIC_InitStruct.NVIC_IRQChannel = TIM3_IRQn;

    NVIC_InitStruct.NVIC_IRQChannelPriority = 2;

    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;

    NVIC_Init(&NVIC_InitStruct);

        TIM3->CR1|=(1<<0);//enable tim1

}

 

void ADCs_Init(void)

{

        hdl_adcInit();

        delay_ms(5000);

        // Setup the filtered ADC value filters

        adcFilteredAdcVal[ADC_MEAS_VS_INDEX] = _ADC_GetSingleReading(_ADC_VS_CH);

        adcFilterSum[ADC_MEAS_VS_INDEX] = (adcFilteredAdcVal[ADC_MEAS_VS_INDEX] << ADC_V_FILTER_SHIFT);

        adcFilteredAdcVal[ADC_MEAS_IS_INDEX] = _ADC_GetSingleReading(_ADC_IS_CH);

        adcFilterSum[ADC_MEAS_IS_INDEX] = (adcFilteredAdcVal[ADC_MEAS_IS_INDEX] << ADC_I_FILTER_SHIFT);

        adcFilteredAdcVal[ADC_MEAS_VB_INDEX] = _ADC_GetSingleReading(_ADC_VB_CH);

        adcFilterSum[ADC_MEAS_VB_INDEX] = (adcFilteredAdcVal[ADC_MEAS_VB_INDEX] << ADC_V_FILTER_SHIFT);

        adcFilteredAdcVal[ADC_MEAS_IB_INDEX] = _ADC_GetSingleReading(_ADC_IB_CH);

        adcFilterSum[ADC_MEAS_IB_INDEX] = (adcFilteredAdcVal[ADC_MEAS_IB_INDEX] << ADC_I_FILTER_SHIFT);

        TIM3_init();

}

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// Measurement indices (first 4 must be measured ADC values)

#define ADC_NUM_MEASUREMENTS 6

 

#define _ADC_VS_CH 4

#define _ADC_IS_CH 2

#define _ADC_VB_CH 3

#define _ADC_IB_CH 1

#define _ADC_TE_CH 6

#define _ADC_TI_CH 5

 

#define ADC_MEAS_VS_INDEX    (_ADC_VS_CH-1)//0

#define ADC_MEAS_IS_INDEX    (_ADC_IS_CH-1)//1

#define ADC_MEAS_VB_INDEX    (_ADC_VB_CH-1)//2

#define ADC_MEAS_IB_INDEX    (_ADC_IB_CH-1)//3

#define ADC_MEAS_TI_INDEX    (_ADC_TI_CH-1)//4

#define ADC_MEAS_TE_INDEX    (_ADC_TE_CH-1)//5

//

// Low-pass digital filter parameters

//  From: https://www.edn.com/design/systems-design/4320010/A-simple-software-lowpass-filter-suits-embedded-system-applications

//

//  K        Bandwidth (normalized to 1Hz)     Rise Time (Samples)

//  1        0.1197                            3

//  2        0.0466                            8

//  3        0.0217                            16

//  4        0.0104                            34

//  5        0.0051                            69

//  6        0.0026                            140

//  7        0.0012                            280

//  8        0.0007                            561

//

#define ADC_V_FILTER_SHIFT  3

#define ADC_I_FILTER_SHIFT  6

 

// ADC Interrupt control macros

#define _ADC_DIS_INT() TIM3->CR1&=~(1<<0) 

#define _ADC_EN_INT()  TIM3->CR1|=(1<<0)