STM32之外部中断/时间控制器(EXTI)

一、EXTI 管理控制23个中断/事件，每个中断/事件 都对应一个边沿检测器，可以实现信号输入的上升沿检测和下降沿检测。 EXTI可实现对每个中断/事件线单独配置，

可以单独配置为中断或事件，以及触发事件的属性。

二、EXTI的功能框图，见具体资料手册。

三、EXIT中断/事件线

#define EXTI_Line0       ((uint32_t)0x00001)     /*!< External interrupt line 0   PX0(X可为 A,B,C,D,E,F,G,H,I)*/
#define EXTI_Line1       ((uint32_t)0x00002)     /*!< External interrupt line 1   同上*/
#define EXTI_Line2       ((uint32_t)0x00004)     /*!< External interrupt line 2  */
#define EXTI_Line3       ((uint32_t)0x00008)     /*!< External interrupt line 3 */
#define EXTI_Line4       ((uint32_t)0x00010)     /*!< External interrupt line 4 */
#define EXTI_Line5       ((uint32_t)0x00020)     /*!< External interrupt line 5 */
#define EXTI_Line6       ((uint32_t)0x00040)     /*!< External interrupt line 6 */
#define EXTI_Line7       ((uint32_t)0x00080)     /*!< External interrupt line 7 */
#define EXTI_Line8       ((uint32_t)0x00100)     /*!< External interrupt line 8 */
#define EXTI_Line9       ((uint32_t)0x00200)     /*!< External interrupt line 9 */
#define EXTI_Line10      ((uint32_t)0x00400)     /*!< External interrupt line 10 */
#define EXTI_Line11      ((uint32_t)0x00800)     /*!< External interrupt line 11 */
#define EXTI_Line12      ((uint32_t)0x01000)     /*!< External interrupt line 12 */
#define EXTI_Line13      ((uint32_t)0x02000)     /*!< External interrupt line 13 */
#define EXTI_Line14      ((uint32_t)0x04000)     /*!< External interrupt line 14 */
#define EXTI_Line15      ((uint32_t)0x08000)     /*!< External interrupt line 15 */
#define EXTI_Line16      ((uint32_t)0x10000)     /*!< External interrupt line 16 Connected to the PVD Output   可编程电压检测器输出*/
#define EXTI_Line17      ((uint32_t)0x20000)     /*!< External interrupt line 17 Connected to the RTC Alarm event */
#define EXTI_Line18      ((uint32_t)0x40000)     /*!< External interrupt line 18 Connected to the USB OTG FS Wakeup from suspend event */                                    
#define EXTI_Line19      ((uint32_t)0x80000)     /*!< External interrupt line 19 Connected to the Ethernet Wakeup event */
#define EXTI_Line20      ((uint32_t)0x00100000)  /*!< External interrupt line 20 Connected to the USB OTG HS (configured in FS) Wakeup event  */
#define EXTI_Line21      ((uint32_t)0x00200000)  /*!< External interrupt line 21 Connected to the RTC Tamper and Time Stamp events */                                               
#define EXTI_Line22      ((uint32_t)0x00400000)  /*!< External interrupt line 22 Connected to the RTC Wakeup event */
#define EXTI_Line23      ((uint32_t)0x00800000)  /*!< External interrupt line 23 Connected to the LPTIM Wakeup event */

四、EXTI初始化结构体

typedef struct
{
  uint32_t EXTI_Line;             //中断/事件线 
   
  EXTIMode_TypeDef EXTI_Mode;       //模式

  EXTITrigger_TypeDef EXTI_Trigger;  //触发方式（上升或下降）

  FunctionalState EXTI_LineCmd;   //EXTI使能
    
}EXTI_InitTypeDef;

五、实验：通过按键来触发EXTI,并在中断服务函数中实现对RGB彩灯的亮灭

5.1 流程图