为什么我的STM8S的AD在0V时为0X25~0X30?

只看该作者 · 2008-12-18 21:49

为什么我的STM8S的AD在0V时为0X25~0X30?电压加大还是数据大.
请版主指点.
配置:
void ADC_config(void)
{
    GPIO_Init_TypeDef   GPIO_InitStructure;
  ADC_Init_TypeDef    ADC_InitStructure;
  /*  Init GPIO for ADC */
  GPIO_InitStructure.GPIO_Mode = GPIO_MODE_IN_FL_NO_IT ;
  GPIO_InitStructure.GPIO_Pin = ( VTV | VEC | Z_V | XYV | FXV | VC | VD | V01 );
  GPIO_Init(PBPORT, &GPIO_InitStructure);

    GPIO_InitStructure.GPIO_Mode = GPIO_MODE_IN_FL_NO_IT ;
  GPIO_InitStructure.GPIO_Pin = ( V02 | ADCELSE );
  GPIO_Init(PEPORT, &GPIO_InitStructure);
    ADC_DeInit();
  enableInterrupts();

    /* Initialize right data alignement */
  ADC_InitStructure.ADC_Align = ADC_ALIGN_RIGHT;
  /* Disable the schmitt trigger on channel 9 */
  ADC_InitStructure.ADC_SchmittTriggerChannel = ADC_SCHMITTTRIG_ALL;
  ADC_InitStructure.ADC_SchmittTriggerState = DISABLE;
  /* Analog channel to convert */
  ADC_InitStructure.ADC_Channel = ADC_CHANNEL_1;
  /* Select Conversion mode */
  ADC_InitStructure.ADC_ConversionMode  = ADC_CONVERSIONMODE_SINGLE;
  /* Init ADC peripheral according to ADC_InitStructure */
  ADC_Init(&ADC_InitStructure);
  /* Enable EOC interrupt */

}
读是这样的:
ADC_StartConversion();
Delay(100);
Conversion_Value = ADC_GetConversionValue();
ADC_ClearFlag();