STM32之中断与事件---一个使用GPIO作为外部中断的示例

1.GPIO 的正确设置

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); //PD3作为外部中断引脚

/**
* @brief Selects the GPIO pin used as EXTI Line.
* @param GPIO_PortSource: selects the GPIO port to be used as source for EXTI lines.
* This parameter can be GPIO_PortSourceGPIOx where x can be (A..G).
* @param GPIO_PinSource: specifies the EXTI line to be configured.
* This parameter can be GPIO_PinSourcex where x can be (0..15).
* @retval None
*/
void GPIO_EXTILineConfig(uint8_t GPIO_PortSource, uint8_t GPIO_PinSource)

2.中断初始化

EXTI_InitTypeDef EXTI_InitStructure;

// Configure EXTI Line3 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 Line4 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);

/*******************************************************************************
* 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);
    }
}

void vcm_airbag_exti_set(void)
{
    EXTI_InitTypeDef EXTI_InitStructure;
	NVIC_InitTypeDef NVIC_InitStructure;
	GPIO_InitTypeDef GPIO_InitStructure;

	/* Enable key GPIO clock */
  	RCC_AHB1PeriphClockCmd(AIRBAG_GPIO_RCC, ENABLE);

	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
	GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
	GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;

	/* Configure  pin(PD_15): airbag gpio */
    GPIO_InitStructure.GPIO_Pin = AIRBAG_GPIO_PIN;
    GPIO_Init(AIRBAG_GPIO_PORT, &GPIO_InitStructure);

	RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE); 			//´ò¿ªEXTIʱÖÓ
	SYSCFG_EXTILineConfig(AIRBAG_EXTI_PORT, AIRBAG_EXTI_PIN);		//ÉèÖÃPD15ΪEXTI

    /* Configure  EXTI  */
//	EXTI_DeInit();
    EXTI_InitStructure.EXTI_Line = AIRBAG_EXTI_LINE; 	//ÉèÖÃÒý½Å
    EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;	//ÉèÖÃΪÍⲿÖжÏģʽ
    EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling;  // ÉèÖÃÉÏÉýºÍϽµÑض¼¼ì²â
    EXTI_InitStructure.EXTI_LineCmd = ENABLE;				 //ʹÄÜÍⲿÖжÏÐÂ״̬
    EXTI_Init(&EXTI_InitStructure);  						 //¸ù¾ÝEXTI_InitStructÖÐÖ¸¶¨µÄ²ÎÊý³õʼ»¯ÍâÉèEXTI¼Ä´æÆ÷

  
	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;				   //ʹÄÜÍⲿÖжÏͨµÀ	
	NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F;		  //ÏÈÕ¼ÓÅÏȼ¶4λ,¹²16¼¶
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F;  //ÏÈÕ¼ÓÅÏȼ¶0λ,´ÓÓÅÏȼ¶4λ
	NVIC_Init(&NVIC_InitStructure);								  //¸ù¾ÝNVIC_InitStructÖÐÖ¸¶¨µÄ²ÎÊý³õʼ»¯ÍâÉèNVIC¼Ä´æÆ÷
}

void EXTI15_10_IRQHandler(void)
{
	rt_interrupt_enter();

	/* °²È«ÆøÄÒÓ²Ïß¼ì²â´¦Àí¡¡*/
	vcm_airbag_exti_check();
	/* GPSÌìÏß¿ªÂ·¼ì²â´¦Àí¡¡*/
	gps_exti_check();

	rt_interrupt_leave();
}

void vcm_airbag_exti_check(void)
{
	//¼ì²éµ±Ç°ÖжϵÄ״̬ÊÇ·ñºÏ·¨
	if(EXTI_GetITStatus(AIRBAG_EXTI_LINE) != RESET)
	{	
		//¶ÁÈ¡¹Ü½ÅµÄ״̬,ÕâÀï·µ»Ø0±íʾ°²È«ÆøÄÒ±¬¿ª
		if(0 ==GPIO_ReadInputDataBit(AIRBAG_GPIO_PORT,AIRBAG_GPIO_PIN))
		{ 
			recv_frame.bus_type = BTYPE_HS_CAN;
			recv_frame.id = 0x545;
			recv_frame.data_buff[0] = 0x00;
			recv_frame.data_buff[1] = 0x01;
			recv_frame.data_buff[2] = 0x00;
			recv_frame.data_buff[3] = 0x00;
			recv_frame.data_buff[4] = 0x00;
			recv_frame.data_buff[5] = 0x00;
			recv_frame.data_buff[6] = 0x00;
			recv_frame.data_buff[7] = 0x00;
			VCM_DEBUG("[vcm] warning: airbag gpio interrupt rising.\r\n");
		}
		else
		{
			recv_frame.bus_type = BTYPE_HS_CAN;
			recv_frame.id = 0x545;
			recv_frame.data_buff[0] = 0x00;
			recv_frame.data_buff[1] = 0x00;
			recv_frame.data_buff[2] = 0x00;
			recv_frame.data_buff[3] = 0x00;
			recv_frame.data_buff[4] = 0x00;
			recv_frame.data_buff[5] = 0x00;
			recv_frame.data_buff[6] = 0x00;
			recv_frame.data_buff[7] = 0x00;
			VCM_DEBUG("[vcm] warning: airbag gpio interrupt falling.\r\n");
		}
		rt_mq_send(&recv_frame_mq,&recv_frame,sizeof(can_bus_frame));
		//ÇåÖжϱê־λ
		EXTI_ClearITPendingBit(AIRBAG_EXTI_LINE);		
	}	
}