用GD32F103RCT6的TIM2捕获中断有丢中断的现象？

发表于 2022-7-28 10:55

用GD32F103RCT6芯片的TIM2做两咱频率测量，有时捕获中断有丢中断的现象？即有时有两个脉冲输入，但CPU只调用TIM2中断函数一次，导致频率计数不对。溢出中断也有这种情况，明明已经发生了溢出但CPU不调TIM2中断函数，通多次测试发现，当在CPU调用TIM2中断函数并手动清除中断标志位时，如果这个发生另一个TIM2中断，这时置位TIM2中断标志就有可能不成功。有没有朋友知道是什么原因？

发表于 2022-7-29 09:59

可以把代码发出来看看吗

发表于 2022-7-29 11:10

这是我的定时器配置函数与中断函数
void Timer2_Configuration(void)
{
TIM_ICInitTypeDef  TIM_ICInitStructure;
TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;

TIM_DeInit(TIM2);

TIM_TimeBaseStructure.TIM_Period = 49999; //0xFFFF;
TIM_TimeBaseStructure.TIM_Prescaler = 71;    //1M
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;

TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);

TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM_ICInitStructure.TIM_ICFilter = 0xF;
TIM_ICInit(TIM2, &TIM_ICInitStructure);

TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM_ICInitStructure.TIM_ICFilter = 0xF;
TIM_ICInit(TIM2, &TIM_ICInitStructure);

TIM_ClearFlag(TIM2, TIM_FLAG_Update);
TIM_ITConfig(TIM2, TIM_IT_CC1 | TIM_IT_CC2 | TIM_IT_Update, ENABLE);
TIM_Cmd(TIM2, ENABLE);
}

vu16 T2_CCR;
vu16 T2_SR;

void TIM2_IRQHandler(void)
{
T2_SR = TIM2->SR;

if(T2_SR & 2) //通道1
{

      T2_CCR = TIM2->CCR1;
      TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);

      if(U_Freq_Count == 0)
      {
         U_Freq_First_Cap = T2_CCR;
         U_T2_OverFlow = 0;
      }
      U_Freq_Count++;
      U_T2_OverFlowForErr = 0;
      if((U_T2_OverFlow > T2_OverFlowForFreq - 2) && (U_T2_OverFlow > 4))
      {
         if(U_Freq_Count > 1)
         {
            U_Freq_Last_Cap    = T2_CCR;
            U_Freq_First_Cap_Bak = U_Freq_First_Cap;
            U_Freq_First_Cap    = U_Freq_Last_Cap;
            U_Freq_Count_Bak    = U_Freq_Count;
            U_Freq_Count       = 1;
            U_T2_OverFlow_Bak = U_T2_OverFlow;
            U_T2_OverFlow       = 0;
            U_En_Freq_Calculate  = TRUE;
         }
      }
}

if(T2_SR & 4) //通道2
{
      T2_CCR = TIM2->CCR2;
      TIM_ClearITPendingBit(TIM2, TIM_IT_CC2);
      if(I_Freq_Count == 0)
      {
         I_Freq_First_Cap = T2_CCR;
         I_T2_OverFlow = 0;
      }
      I_Freq_Count++;
      if((I_T2_OverFlow > T2_OverFlowForFreq - 2) && (I_T2_OverFlow > 4))
      {
         if(I_Freq_Count > 1)
         {
            I_Freq_Last_Cap    = T2_CCR;
            I_Freq_First_Cap_Bak = I_Freq_First_Cap;
            I_Freq_First_Cap    = I_Freq_Last_Cap;
            I_Freq_Count_Bak    = I_Freq_Count;
            I_Freq_Count       = 1;
            I_T2_OverFlow_Bak = I_T2_OverFlow;
            I_T2_OverFlow       = 0;
            I_En_Freq_Calculate  = TRUE;
         }
      }
}

if(T2_SR & 1) //溢出
{
      TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
      U_T2_OverFlow++;
      if(U_T2_OverFlow> T2_OverFlowForFreq)
      {
         U_Freq_Count  = 0;
         U_T2_OverFlow = 0;
         U_Freq_Err = TRUE;

      }
      I_T2_OverFlow++;
      if(I_T2_OverFlow > T2_OverFlowForFreq)
      {
         I_Freq_Count  = 0;
         I_T2_OverFlow = 0;
         I_Freq_Err = TRUE;

      }
}
}

发表于 2022-7-29 17:26

把TIM_ICInitStructure.TIM_ICFilter = 0xF改为0试试

发表于 2022-8-1 08:42

把TIM_ICInitStructure.TIM_ICFilter = 0xF改为0，这个我也试过，不能解决问题，我的理解是，在用TIM_ClearITPendingBit(TIM2, TIM_IT_CC2)清中断标志位时，这时硬件正要置位中断标志位，这时硬件操作就被放弃了。

发表于 2022-8-1 19:35

有没有勘误手册之类的，说什么没有

发表于 2022-8-2 11:28

GD32好像没有勘误手册，我用STM32芯片没有这个问题？

发表于 2022-8-9 09:20

应该硬件操作优先级更高，你说的没有操作应该是已经操作了不过状态一致而已。比如你就在这个中断里执行，比还会进入这个中断吗？同一个中断没法优先级或者排队等待的，当你跳出中断后就会硬件改变状态了，所以就会传被“吃”的现象。

发表于 2022-8-11 15:20

谢谢<span style="margin: 0px; padding: 0px; color: rgb(144, 153, 172); font-family: "Microsoft yahei"; background-color: rgb(255, 255, 255); text-decoration-line: none !important;"><a target="_blank" style="margin: 0px; padding: 0px; color: rgb(144, 153, 172); font-family: "Microsoft yahei"; background-color: rgb(255, 255, 255); text-decoration-line: none !important;">qintian0303</a>的回答，我测的两路频率都是1000Hz，一些一个中断函数执行时间不会大于1mS，所以在执行中断函数时，相同中断不会发生，所以不会因中断函数执行时间过长导致脉冲丢失的情况！</span>

用GD32F103RCT6的TIM2捕获中断有丢中断的现象？