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
[cpp] view plain copy

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

其中GPIO_EXITLineConfig函数的声明如下:

[cpp] view plain copy

/**
* @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[cpp] view plain copy

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.[cpp] view plain copy

/* 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 中写入中断处理函数

[cpp] view plain copy

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

另一个示例:

配置如下:

[cpp] view plain copy

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¿ªEXTIÊ±ÖÓ
SYSCFG_EXTILineConfig(AIRBAG_EXTI_PORT, AIRBAG_EXTI_PIN); //ÉèÖÃPD15ÎªEXTI
/* Configure EXTI */
// EXTI_DeInit();
EXTI_InitStructure.EXTI_Line = AIRBAG_EXTI_LINE; //ÉèÖÃÒý½Å
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt; //ÉèÖÃÎªÍâ²¿ÖÐ¶ÏÄ£Ê½
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Rising_Falling; // ÉèÖÃÉÏÉýºÍÏÂ½µÑØ¶¼¼ì²â
EXTI_InitStructure.EXTI_LineCmd = ENABLE; //Ê¹ÄÜÍâ²¿ÖÐ¶ÏÐÂ×´Ì¬
EXTI_Init(&EXTI_InitStructure); //¸ù¾ÝEXTI_InitStructÖÐÖ¸¶¨µÄ²ÎÊý³õÊ¼»¯ÍâÉèEXTI¼Ä´æÆ÷
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //Ê¹ÄÜÍâ²¿ÖÐ¶ÏÍ¨µÀ
NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0F; //ÏÈÕ¼ÓÅÏÈ¼¶4Î»,¹²16¼¶
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0F; //ÏÈÕ¼ÓÅÏÈ¼¶0Î»,´ÓÓÅÏÈ¼¶4Î»
NVIC_Init(&NVIC_InitStructure); //¸ù¾ÝNVIC_InitStructÖÐÖ¸¶¨µÄ²ÎÊý³õÊ¼»¯ÍâÉèNVIC¼Ä´æÆ÷
}