1.GPIO 的正確設(shè)置

 GPIO_InitTypeDef GPIO_InitStructure;

  /* Enable GPIOD clock */
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD, ENABLE);

/* Configure PD.03, PC.04, as input floating */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3 | GPIO_Pin_4 ;
    
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
  GPIO_Init(GPIOD, &GPIO_InitStructure);
 
  GPIO_EXTILineConfig(GPIO_PortSourceGPIOD, GPIO_PinSource3);

2.設(shè)置中斷類型，注冊申請中斷

EXTI_InitTypeDef EXTI_InitStructure;

 
  // Configure EXTI Line9 to generate an interrupt on falling edge
  EXTI_InitStructure.EXTI_Line = EXTI_Line3;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
  EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  EXTI_Init(&EXTI_InitStructure);

  GPIO_EXTILineConfig(GPIO_PortSourceGPIOD, GPIO_PinSource4);

  // Configure EXTI Line9 to generate an interrupt on falling edge
  EXTI_InitStructure.EXTI_Line = EXTI_Line4;
  EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
  EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
  EXTI_InitStructure.EXTI_LineCmd = ENABLE;
  EXTI_Init(&EXTI_InitStructure);

3.在NVIC_Configuration 中Configures the NVIC and Vector Table base address.

  /* Configure the Priority Group to 2 bits */
  NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);

  /* enabling interrupt */
  NVIC_InitStructure.NVIC_IRQChannel=TIM2_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

  /* Enable the EXTI3 Interrupt on PD.3 */
  NVIC_InitStructure.NVIC_IRQChannel = EXTI3_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

    /* Enable the EXTI4 Interrupt on PD.4 */
  NVIC_InitStructure.NVIC_IRQChannel = EXTI4_IRQChannel;
  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);

4.在stm32f0x_it.c 中寫入 中斷處理函數(shù)

/*******************************************************************************
* Function Name  : EXTI3_IRQHandler
* Description    : This function handles External interrupt Line 3 request.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void EXTI3_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line3) != RESET)
  {
   // Led_RW_ON();
    GPIO_SetBits(GPIOC, GPIO_Pin_4| GPIO_Pin_5 );
   
   
    /* Clear the EXTI line 9 pending bit */
    EXTI_ClearITPendingBit(EXTI_Line3);
  }
}

/*******************************************************************************
* Function Name  : EXTI4_IRQHandler
* Description    : This function handles External interrupt Line 4 request.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void EXTI4_IRQHandler(void)
{
 if(EXTI_GetITStatus(EXTI_Line4) != RESET)
  {
    //Led_RW_OFF();
    GPIO_ResetBits(GPIOC, GPIO_Pin_4 | GPIO_Pin_5);
    /* Clear the EXTI line 9 pending bit */
    EXTI_ClearITPendingBit(EXTI_Line4);
  }
}