STM32 TIM3 TROG 触发ADC 询问

numajinfei · 发表于 2015-9-6 09:12:27

用的是原子哥V2.2板子做TIM3 TROG 500ms触发ADC实验(没有用到DMA)，板子上面的STM_ADC直接接板载3.3v了，但实验下来发现输出的数据由大到小，由小到大这样变化，类似一个波形，而且最大值得出的电压值只有3507（2.825V）。

（串口显示的值是ADC转化值，不是扩大100倍的电压值）

现将主要配置代码附上，烦请各位帮分析分析，哪里配置还有遗漏或不当，谢谢！

[mw_shl_code=c,true]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)); }[/mw_shl_code]

[mw_shl_code=c,true]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); }[/mw_shl_code]

[mw_shl_code=c,true]/** * @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; } } [/mw_shl_code]