stm32f103ve AD DMA采样，64点FFT误差问题

lixglixg · 发表于 2019-10-22 15:01:51

本帖最后由 lixglixg 于 2019-10-22 15:03 编辑

请教下，交流电采样，使用下面初始化，

修改下边红色部分参数，64点FFT后，数据变化很大，应如何解决，转换后电压从230到330变化
理论上应该没有影响的

void ADC1_onfiguration(void)
{
ADC_InitTypeDef ADC_InitStructure;

//#define ADC_SampleTime_1Cycles5
//#define ADC_SampleTime_7Cycles5
//#define ADC_SampleTime_13Cycles5
//#define ADC_SampleTime_28Cycles5
//#define ADC_SampleTime_41Cycles5
//#define ADC_SampleTime_55Cycles5

#define T_AD_CLK  ADC_SampleTime_1Cycles5  //修改这个值，FFT后数据变化很大，应如何解决，谢谢

AD_Gpio();
  DMA1_1_onfiguration();
  DMA_Cmd(DMA1_Channel1, ENABLE);//使能DMA1
  ADC_DeInit(ADC1); //复位DMA寄存器
  ADC_DeInit(ADC2); //复位DMA寄存器
  /* ADC1 configuration ------------------------------------------------------*/
  ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult; //
  ADC_InitStructure.ADC_ScanConvMode = ENABLE ;//
  ADC_InitStructure.ADC_ContinuousConvMode = DISABLE ; //

  ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T3_TRGO  ;//
  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right; //
  ADC_InitStructure.ADC_NbrOfChannel = 6;
  ADC_Init(ADC1, &ADC_InitStructure);

ADC_Cmd(ADC1, ENABLE);/* Enable ADC1 */
  ADC_ResetCalibration(ADC1);//重置校准寄存器
  while(ADC_GetResetCalibrationStatus(ADC1));
  ADC_StartCalibration(ADC1);//开始校准
  while(ADC_GetCalibrationStatus(ADC1));


  ADC_RegularChannelConfig(ADC1, ADC_Channel_15,    1, T_AD_CLK);//
  ADC_RegularChannelConfig(ADC1, ADC_Channel_9,    2, T_AD_CLK);//
  ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 3, T_AD_CLK);//

  ADC_RegularChannelConfig(ADC1, ADC_Channel_5,    4, T_AD_CLK);//

ADC_RegularChannelConfig(ADC1, ADC_Channel_4,    5, T_AD_CLK);//
ADC_RegularChannelConfig(ADC1, ADC_Channel_6,    6, T_AD_CLK);//备用

  ADC_ExternalTrigConvCmd(ADC1,ENABLE);//使能ADC外部触发
  ADC_InitStructure.ADC_Mode = ADC_Mode_RegSimult;
  ADC_InitStructure.ADC_ScanConvMode = ENABLE;
  ADC_InitStructure.ADC_ContinuousConvMode = DISABLE;

  ADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T3_TRGO;
  ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
  ADC_InitStructure.ADC_NbrOfChannel = 6;
  ADC_Init(ADC2, &ADC_InitStructure);

  ADC_Cmd(ADC2, ENABLE);
  ADC_ResetCalibration(ADC2);
  while(ADC_GetResetCalibrationStatus(ADC2));

  /* Start ADC2 calibaration */
  ADC_StartCalibration(ADC2);
  while(ADC_GetCalibrationStatus(ADC2));
  ADC_RegularChannelConfig(ADC2, ADC_Channel_12, 1, T_AD_CLK);//
  ADC_RegularChannelConfig(ADC2, ADC_Channel_13, 2, T_AD_CLK);//
  ADC_RegularChannelConfig(ADC2, ADC_Channel_11, 3, T_AD_CLK);//

  ADC_RegularChannelConfig(ADC2, ADC_Channel_10, 4, T_AD_CLK);//

ADC_RegularChannelConfig(ADC2, ADC_Channel_14, 5, T_AD_CLK);//
ADC_RegularChannelConfig(ADC2, ADC_Channel_7,    6, T_AD_CLK);//

  ADC_ExternalTrigConvCmd(ADC2,ENABLE);//使能ADC外部触发
ADC_DMACmd(ADC1, ENABLE);
  TIM3AD_onfiguration();  //初始化定时器3
}
//=================================================
void DMA1_1_onfiguration(void)
{
DMA_InitTypeDef DMA_InitStructure;
  DMA_DeInit(DMA1_Channel1); //复位DMA寄存器
  DMA_InitStructure.DMA_PeripheralBaseAddr = ((u32)0x4001244C); //AD转换数据地址
  DMA_InitStructure.DMA_MemoryBaseAddr =(unsigned long )MYADIN[0];//DMA通道寄存器地址
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC; //从外设读数据
  DMA_InitStructure.DMA_BufferSize = 6*64;// //数据传输量
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//不执行外设地址增量操作
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//执行存储器增量操作
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;//外设32位数据宽度
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;//存储器32位数据宽度
  DMA_InitStructure.DMA_Mode = DMA_Mode_Circular; //
  DMA_InitStructure.DMA_Priority = DMA_Priority_VeryHigh;//
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;//
  DMA_Init(DMA1_Channel1, &DMA_InitStructure);//初始DMA 通道1
  DMA_ClearFlag(DMA1_FLAG_GL1 | DMA1_FLAG_TC1 ) ;
  DMA_ITConfig(DMA1_Channel1,DMA_IT_TC|DMA_IT_TE ,ENABLE);
}
//=================================================
void TIM3AD_onfiguration(void)
{

TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
  TIM_DeInit(TIM3);//复位
  TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
  TIM_TimeBaseStructure.TIM_Period = 22499 ;//
  TIM_TimeBaseStructure.TIM_Prescaler = 0;//
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;//
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Down ;//
  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
  TIM_ARRPreloadConfig(TIM3,ENABLE); //允许重装 TIM_Period
  TIM_SelectOutputTrigger(TIM3,TIM_TRGOSource_Update);//
  TIM_ClearFlag(TIM3, TIM_FLAG_Update);

}