用STM32F103RET的PB8来做外部中断的问题

只看该作者 · 2013-3-28 20:37

   我做的一个板子上用STM32F103RET6的PB8的IO管脚来接收外部轻触按键输入的中断。我将这个PB8初始化并使能后运行，不去按轻触按键时发现程序总是不断的触发中断，使程序总是处于中断服务当中服务当中。下面是我的中断初始化和中断处理函数的代码，显示输出的计数器在不断的加一计数。这个PB8的管脚只连接了轻触按键，PB8通过10K电阻上拉到3.3V。我用示波器探了这个PB8也没发现有触发中断的脉冲产生，是一个平稳的3.3V。不知道出了什么问题，还望路过的大侠指点小弟。

void Exti_IOPort_Init(void)
{
      EXTI_InitTypeDef EXTI_InitStructure;
      NVIC_InitTypeDef NVIC_InitStructure;

      GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource8);

      EXTI_InitStructure.EXTI_Line =EXTI_Line8;
      EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
      EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
      EXTI_InitStructure.EXTI_LineCmd = ENABLE;
      EXTI_Init(&EXTI_InitStructure);

      NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn;
      NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
      NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
      NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
      NVIC_Init(&NVIC_InitStructure);
}

void EXTI9_5_IRQHandler(void)
{
      unsigned short Itemp;
      ITStatus ItState,FlagState;

      ItState = EXTI_GetITStatus(EXTI_Line8);
      FlagState = EXTI_GetFlagStatus(EXTI_Line8);

      if((ItState != RESET) & (FlagState != RESET))
            {
            KEY2_NUM++;
            EXTI_ClearITPendingBit(EXTI_Line8);
            EXTI_ClearFlag(EXTI_Line8);
            ShowString88(3, 0, "K2 On!Count:");
            ShowCharNum(3, 12, KEY2_NUM);
            }
      for(Itemp=0;Itemp<25536;Itemp++)  ;
}