STM32 按键EXTI方式 使用ST3.0.0库

1：使能EXTI Line时钟和第二功能时钟。

2：配置EXTI Line中断优先级（NVIC）

3：配置EXTI Line IO （哪个引脚，输入模式，初始化）

4：把引脚配置为EXTI Line的中断源（GPIO操作），配置IO口的工作模式

5：配置EXTI Line的工作模式。

==============================================================================

例如：

GPIO_InitTypeDef GPIO_InitStructure;
EXTI_InitTypeDef EXTI_InitStructure;

/* config the extiline(PB0) clock and AFIO clock 使能extiline IO时钟和第二功能时钟*/
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO,ENABLE);

/* config the NVIC(PB0) 配置extiline中断优先级*/
NVIC_Configuration();

/* EXTI line gpio config(PB0) 配置EXTI line gpio */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; // 上拉输入
GPIO_Init(GPIOB, &GPIO_InitStructure);

/* EXTI line(PB0) mode config 选定IO EXTI的IO线和IO口的中断模式 */
GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource0); //选定PB0为中断源

EXTI_InitStructure.EXTI_Line = EXTI_Line0;//把PB0连接到EXTI_Line0中断线上
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt; //中断模式
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling; //下降沿中断
EXTI_InitStructure.EXTI_LineCmd = ENABLE;//使能外部中断
EXTI_Init(&EXTI_InitStructure); //初始化

/*
* 函数名：NVIC_Configuration
* 描述 ：配置嵌套向量中断控制器NVIC
* 输入 ：无
* 输出 ：无
* 调用 ：内部调用
*/
static void NVIC_Configuration(void)
{
NVIC_InitTypeDef NVIC_InitStructure;

/* Configure one bit for preemption priority */
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);

/* 配置P[A|B|C|D|E]0为中断源 */
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}

接下来要写中断函数了

在stm32f10x_it.c中编写中断服务函数

/* I/O线中断，中断线为PB0 */
void EXTI0_IRQHandler(void)
{
if(EXTI_GetITStatus(EXTI_Line0) != RESET) //确保是否产生了EXTI Line中断
{
//LED1 取反
GPIO_WriteBit(GPIOC, GPIO_Pin_3,
(BitAction)((1-GPIO_ReadOutputDataBit(GPIOC, GPIO_Pin_3))));
EXTI_ClearITPendingBit(EXTI_Line0); //清除中断标志位
}
}

要注意的是在中断服务程序完成之后还要记得清除中断标志位.

这里要说明一下中断的分陪

EXTI0

EXTI1

EXTI2

EXTI3

EXTI4

EXTI5-9

EXTI10-15

中断0-4是每个中断线各自用一个中断函数，5-9是共用一个中断函数，10-15共用一个中断函数。

关于中断服务函数的命名的编写方法是：

在startup_stm32f10x_hd.s文件中查找外部中断源

; External Interrupts
DCD WWDG_IRQHandler ; Window Watchdog
DCD PVD_IRQHandler ; PVD through EXTI Line detect
DCD TAMPER_IRQHandler ; Tamper
DCD RTC_IRQHandler ; RTC
DCD FLASH_IRQHandler ; Flash
DCD RCC_IRQHandler ; RCC
DCD EXTI0_IRQHandler ; EXTI Line 0
DCD EXTI1_IRQHandler ; EXTI Line 1
DCD EXTI2_IRQHandler ; EXTI Line 2
DCD EXTI3_IRQHandler ; EXTI Line 3
DCD EXTI4_IRQHandler ; EXTI Line 4
DCD DMA1_Channel1_IRQHandler ; DMA1 Channel 1
DCD DMA1_Channel2_IRQHandler ; DMA1 Channel 2
DCD DMA1_Channel3_IRQHandler ; DMA1 Channel 3
DCD DMA1_Channel4_IRQHandler ; DMA1 Channel 4
DCD DMA1_Channel5_IRQHandler ; DMA1 Channel 5
DCD DMA1_Channel6_IRQHandler ; DMA1 Channel 6
DCD DMA1_Channel7_IRQHandler ; DMA1 Channel 7
DCD ADC1_2_IRQHandler ; ADC1 & ADC2
DCD USB_HP_CAN1_TX_IRQHandler ; USB High Priority or CAN1 TX
DCD USB_LP_CAN1_RX0_IRQHandler ; USB Low Priority or CAN1 RX0
DCD CAN1_RX1_IRQHandler ; CAN1 RX1
DCD CAN1_SCE_IRQHandler ; CAN1 SCE
DCD EXTI9_5_IRQHandler ; EXTI Line 9..5
DCD TIM1_BRK_IRQHandler ; TIM1 Break
DCD TIM1_UP_IRQHandler ; TIM1 Update
DCD TIM1_TRG_COM_IRQHandler ; TIM1 Trigger and Commutation
DCD TIM1_CC_IRQHandler ; TIM1 Capture Compare
DCD TIM2_IRQHandler ; TIM2
DCD TIM3_IRQHandler ; TIM3
DCD TIM4_IRQHandler ; TIM4
DCD I2C1_EV_IRQHandler ; I2C1 Event
DCD I2C1_ER_IRQHandler ; I2C1 Error
DCD I2C2_EV_IRQHandler ; I2C2 Event
DCD I2C2_ER_IRQHandler ; I2C2 Error
DCD SPI1_IRQHandler ; SPI1
DCD SPI2_IRQHandler ; SPI2
DCD USART1_IRQHandler ; USART1
DCD USART2_IRQHandler ; USART2
DCD USART3_IRQHandler ; USART3
DCD EXTI15_10_IRQHandler ; EXTI Line 15..10
DCD RTCAlarm_IRQHandler ; RTC Alarm through EXTI Line
DCD USBWakeUp_IRQHandler ; USB Wakeup from suspend
DCD TIM8_BRK_IRQHandler ; TIM8 Break
DCD TIM8_UP_IRQHandler ; TIM8 Update
DCD TIM8_TRG_COM_IRQHandler ; TIM8 Trigger and Commutation
DCD TIM8_CC_IRQHandler ; TIM8 Capture Compare
DCD ADC3_IRQHandler ; ADC3
DCD FSMC_IRQHandler ; FSMC
DCD SDIO_IRQHandler ; SDIO
DCD TIM5_IRQHandler ; TIM5
DCD SPI3_IRQHandler ; SPI3
DCD UART4_IRQHandler ; UART4
DCD UART5_IRQHandler ; UART5
DCD TIM6_IRQHandler ; TIM6
DCD TIM7_IRQHandler ; TIM7
DCD DMA2_Channel1_IRQHandler ; DMA2 Channel1
DCD DMA2_Channel2_IRQHandler ; DMA2 Channel2
DCD DMA2_Channel3_IRQHandler ; DMA2 Channel3
DCD DMA2_Channel4_5_IRQHandler ; DMA2 Channel4 & Channel5

============================================================================

void GPIO_EXTILineConfig(uint8_t GPIO_PortSource, uint8_t GPIO_PinSource)

把IO引脚配置为 EXTI Line，把IO引脚作为EXTI中断线使用，是IO的第二功能。

GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource0); //选定PB0为中断源(中断线)

==============================================================================

获取中断线的状态

ITStatus EXTI_GetITStatus(uint32_t EXTI_Line)

例如：
if(EXTI_GetITStatus(EXTI_Line0) != RESET) //确保是否产生了EXTI Line中断，也可以不加这条if语句（本人的理解）
{
// LED1 取反
GPIO_WriteBit(GPIOC, GPIO_Pin_3,(BitAction)((1-GPIO_ReadOutputDataBit(GPIOC, GPIO_Pin_3))));
EXTI_ClearITPendingBit(EXTI_Line0); //清除中断标志位
}

============================================================================================

void EXTI_ClearITPendingBit(uint32_t EXTI_Line)

例如：

EXTI_ClearITPendingBit(EXTI_Line0); //清除中断标志位 Clears the EXTI line pending bits. 清EXTI Line0的中断标志位。