STM32的TIM3 TROG触发ADC疑问

某人提问时间：2015-9-5 17:45 /

各位，小弟在使用STM32的TIM3 TROG触发ADC1的测试中，发现串口输出的ADC值会由大到小，由小到大这样重复变化，类似一个波动效果。
[img]file:///C:\Users\Administrator\AppData\Roaming\Tencent\Users\735340838\QQ\WinTemp\RichOle\K0O4EYN3]R9ZEI(XNPX$0@F.png[/img]

用的是战舰stm32开发板，采用TIM3 500ms触发一次ADC转换，没有用DMA，使用的是ADC中断中读取ADC转化值，具体代码为：
  static void ADC1_Mode_Config(void)//ADC1_Mode_Config(uint32_t ADC_ConvertedVal)
{
// DMA_InitTypeDef DMA_InitInstructure;
ADC_InitTypeDef ADC_InitStruct;
NVIC_InitTypeDef NVIC_InitStructure ;

RCC_ADCCLKConfig(RCC_PCLK2_Div6);

ADC_DeInit(ADC1);
ADC_InitStruct.ADC_Mode = ADC_Mode_Independent;
ADC_InitStruct.ADC_NbrOfChannel = 1;
ADC_InitStruct.ADC_ContinuousConvMode = DISABLE;
ADC_InitStruct.ADC_ScanConvMode = DISABLE;
ADC_InitStruct.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T3_TRGO;
ADC_InitStruct.ADC_DataAlign =ADC_DataAlign_Right;
ADC_Init(ADC1,&ADC_InitStruct);

NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0) ;
NVIC_InitStructure.NVIC_IRQChannel = ADC1_2_IRQn ;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0 ;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 9 ;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE ;
NVIC_Init(&NVIC_InitStructure);

ADC_ExternalTrigConvCmd(ADC1,ENABLE);
ADC_RegularChannelConfig(ADC1,ADC_Channel_11,1,ADC_SampleTime_55Cycles5);

ADC_ITConfig(ADC1, ADC_IT_EOC, ENABLE);
ADC_Cmd(ADC1,ENABLE);

ADC_ResetCalibration(ADC1);
while(ADC_GetResetCalibrationStatus(ADC1));
ADC_StartCalibration(ADC1);
while(ADC_GetCalibrationStatus(ADC1));
}

void TIM3_Configration(void)
{

TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
NVIC_InitTypeDef NVIC_InitStruct;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);

TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInitStruct.TIM_Period = 4999;
TIM_TimeBaseInitStruct.TIM_Prescaler = 7199;
TIM_TimeBaseInit(TIM3,&TIM_TimeBaseInitStruct);

TIM_SelectOutputTrigger(TIM3,TIM_TRGOSource_Update); //??TRGO???????????
TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable);

TIM_Cmd(TIM3,ENABLE);
}

/**
  * @brief  This function handles ADC1 and ADC2 global interrupts requests.
  * @param  None
  * @retval None
  */
#if defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || defined (STM32F10X_HD_VL)
void ADC1_IRQHandler(void)
#else
void ADC1_2_IRQHandler(void)
#endif
{
if(ADC_GetITStatus(ADC1, ADC_IT_EOC))
{
ADC_ClearITPendingBit(ADC1, ADC_IT_EOC);
ADC_ConvertedValue = ADC_GetConversionValue(ADC1);
sSysFlagBit.CANRx_G = TRUE;
}
}

  大伙帮分析分析看，是否哪里配置的还有问题，多谢！！！

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