求助！！！！！！！！！！！！！！急~~~~~~~~~~~~~~~~~~~~~~~~~ADC问题

Echo_Rabbit · 发表于 2013-9-8 22:37:02

用8位精度的ADC 参考电压为3v   采样周期为239.5     ADC的频率为2.25Mhz    左对齐的方式   采样 500hz，1v的正弦波

用串口显示的数据为标准值的5倍左右

大神们给看看哪里出问题了

int main(void)
{
u16 VolValue=0;
RCC_INIT_();
GPIO_INIT_();
NVIC_INIT_();
ADC_INIT_();
USART_INIT_();
while(1)
{
  VolValue=ADC_GetConversionValue(ADC1)&0xff00;
  printf("\r\n %d \r\n",VolValue/16);
// _delay_ms(2);
}
}

void RCC_INIT_(void)
{
ErrorStatus HSEStartUpStatus;
  RCC_DeInit();
  RCC_HSEConfig(RCC_HSE_ON);
  HSEStartUpStatus=RCC_WaitForHSEStartUp();
  if(HSEStartUpStatus==SUCCESS)
  {
     RCC_HCLKConfig(RCC_SYSCLK_Div1);
    RCC_PCLK2Config(RCC_HCLK_Div4);
    RCC_PCLK1Config(RCC_HCLK_Div2);
    FLASH_SetLatency(FLASH_Latency_2);
    FLASH_PrefetchBufferCmd(FLASH_PrefetchBuffer_Enable);
    //选择PLL时钟源为HSE1分频，倍数频为9，则PLL=8MHZ*9=72MHZ
    RCC_PLLConfig(RCC_PLLSource_HSE_Div1,RCC_PLLMul_9);
    RCC_PLLCmd(ENABLE);
    while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY)==RESET);
    RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
   while(RCC_GetSYSCLKSource()!=0x08);
  }
  //RCC_APB1PeriphClockCmd(RCC_APB1Periph_BKP | RCC_APB1Periph_PWR,ENABLE);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_ADC1 |RCC_APB2Periph_GPIOA|RCC_APB2Periph_GPIOB| RCC_APB2Periph_USART1, ENABLE);
}

void GPIO_INIT_(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
//串口
//PA9 USART1 Tx
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_Init(GPIOA , &GPIO_InitStructure);
//PA10 USART1 Rx
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA , &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode =GPIO_Mode_AIN;
GPIO_Init(GPIOB , &GPIO_InitStructure);
}

void NVIC_INIT_(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
//USART1
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}

int fputc(int ch,FILE *f)
{
USART_SendData(USART1,(u8)ch);
while(USART_GetFlagStatus(USART1,USART_FLAG_TC)==RESET);
return ch;
}

void ADC_INIT_(void)
{
ADC_InitTypeDef ADC_InitStructure;

RCC_ADCCLKConfig(RCC_PCLK2_Div8);
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_Left;
ADC_InitStructure.ADC_NbrOfChannel = 1;
ADC_Init(ADC1, &ADC_InitStructure);

ADC_RegularChannelConfig(ADC1,ADC_Channel_8,1,ADC_SampleTime_239Cycles5);
ADC_Cmd(ADC1, ENABLE);
ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));
ADC_SoftwareStartConvCmd(ADC1,ENABLE);
}

正点原子 · 发表于 2013-9-8 23:12:31

串口值是多少？配置貌似无问题。

Echo_Rabbit · 发表于 2013-9-9 08:44:54

回复【2楼】正点原子:
---------------------------------
原子大哥  下面是一部分的串口显示值

320

  0

  576

  0

  480

  0

  144

  48

  0

  544

  0

  608

  0

  240

  0

  0

  592

  0

  576

  0

  112

  0

  0

  560

  0

  512

  0

  192

  0

  0

  592

  0

  432