EXTI外部中断触发：神舟IV

先设置两个中断输入口 PA6/PA7 浮空输入 PA6下降沿，PA7上升沿

void EXTI_Config(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    EXTI_InitTypeDef EXTI_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
    
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource6);
    GPIO_EXTILineConfig(GPIO_PortSourceGPIOA, GPIO_PinSource7);

    // Configure EXTI Line6 to generate an interrupt on falling edge 
    EXTI_InitStructure.EXTI_Line = EXTI_Line6;
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    EXTI_Init(&EXTI_InitStructure);

    EXTI_InitStructure.EXTI_Line = EXTI_Line7;
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising;
    EXTI_Init(&EXTI_InitStructure);

    /* Enable the EXTI15_10 Interrupt */
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
    NVIC_InitStructure.NVIC_IRQChannel = EXTI9_5_IRQn; //EXTI15_10_IRQChannel;
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);                                         
}

设置两个pin PB0/PB1（推挽输出） 为中断输入PA6/PA7提供中断源

void EXTI_Input_Config(void)
{
    /* Config PB0 for PA6 and PB1 for PA7 */
   GPIO_InitTypeDef GPIO_InitStructure;
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO , ENABLE);  //RCC_APB2Periph_AFIO
  
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1;   
   /* 推挽输出 */
   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
   GPIO_Init(GPIOB, &GPIO_InitStructure);

}

按键4按下后检测PB0状态，然后位取反，分别接入PA6，PA7，串口显示OK

void EXTI0_IRQHandler(void)
{
  u8 i;
  /* Key4 */
  if(EXTI_GetITStatus(EXTI_Line0) != RESET)
  {
    Led_Turn_off_all();
    Led_Turn_on_4();

    printf("\n\r Key 4 interrupt \n\r");
    if(GPIO_ReadOutputDataBit(GPIOB, GPIO_Pin_0)) 
    {
     printf("\n\r PB0 Set \n\r"); 
     GPIO_ResetBits(GPIOB, GPIO_Pin_0);
     for(i=0;i<100;i++);
    }
    else
    {
     printf("\n\r PB0 Reset \n\r");
     GPIO_SetBits(GPIOB, GPIO_Pin_0);
     for(i=0;i<100;i++);
    }

    if(GPIO_ReadOutputDataBit(GPIOB, GPIO_Pin_0)) 
    {
     printf("\n\r PB0 Set \n\r"); 
    }
    else
    {
     printf("\n\r PB0 Reset \n\r");
    }

    /* Clear the EXTI Line 0 */
    EXTI_ClearITPendingBit(EXTI_Line0);
  }
}

PA6/7触发后中断处理函数

void EXTI9_5_IRQHandler(void)
{
  if(EXTI_GetITStatus(EXTI_Line6) != RESET)
  {
    printf("\n\r PA_6 interrupt \n\r");
    
    /* Clear the EXTI Line 6 */
    EXTI_ClearITPendingBit(EXTI_Line6);
  }
  if(EXTI_GetITStatus(EXTI_Line7) != RESET)
  {
    printf("\n\r PA_7 interrupt \n\r");
    
    /* Clear the EXTI Line 7 */
    EXTI_ClearITPendingBit(EXTI_Line7);
  }
  
}