1. 配置PA4，PA5为外部中断
/ Y: i2 r; F8 [! A+ ^

1. void EXTI_Config(void)
     B( g/ _. Z& ^- B) q: N. x5 J3 y
2. {
   7 {+ @! n8 [: a* C
3.   EXTI_InitTypeDef   EXTI_InitStructure;
   ) l6 w, h4 l" Y& k
4.   GPIO_InitTypeDef   GPIO_InitStructure;
   
5.   NVIC_InitTypeDef   NVIC_InitStructure;
   # l% b4 u( Q2 s
6. 
   
7.   /* Enable GPIOA clock */
   
8.   RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA|RCC_AHBPeriph_GPIOF, ENABLE);
   , e8 N# d! x, K3 L! x) s  }0 y. B! D
9. 
   , P0 V' r! |# b( J
10.   /* Configure PA4&PA5 pin as input floating */
    
11.   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4|GPIO_Pin_5;
    
12.   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;
    % I( s4 h# g$ C3 g7 @8 {9 S" `
13.   GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    
14.   GPIO_Init(GPIOA, &GPIO_InitStructure);
    - G1 P, W" I) E& X- K$ u* V% Y' d
15. 
    
16.   /* Enable SYSCFG clock */
      r$ \4 D; o6 M& B2 `
17.   RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);
    8 P% P, j  S4 j: p1 @& ?+ q
18. 
    + |, B2 g. {# N) M( h
19.   /* Connect EXTI4 Line to PA4 pin */
    ( n- h8 M) e9 P) F  t$ u5 j
20.   SYSCFG_EXTILineConfig(EXTI_PortSourceGPIOA, EXTI_PinSource4|EXTI_PinSource5);
    % V( e* t+ h! w) b. Z% |
21. 
    
22.   /* Configure EXTI4&EXTI5 line */
    
23.   EXTI_InitStructure.EXTI_Line = EXTI_Line4|EXTI_Line5;
    
24.   EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
    # o! O* e; ]. A# n
25.   EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
    ; n6 H- t& W& U0 ~& \3 R7 X
26.   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
    
27.   EXTI_Init(&EXTI_InitStructure);
    : g2 d, L; q% _( f2 q- b0 m0 d
28. 
    
29.   /* Enable and set EXTI4&EXTI5 Interrupt */
    : [$ D" `8 N' p  W) F' s
30.   NVIC_InitStructure.NVIC_IRQChannel = EXTI4_15_IRQn;
    
31.   NVIC_InitStructure.NVIC_IRQChannelPriority = 0x00;
    3 N6 p, G& O% \% X& _
32.   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    2 q8 F: B5 E4 Y  _' G, |
33.   NVIC_Init(&NVIC_InitStructure);
    
34. }

复制代码

2， 外部触发中断函数
) Z/ Q# {: |$ f# t; D7 T" `

1. void EXTI4_15_IRQHandler(void)
   
2. {
   # u) @+ I! j) k; Z* y
3.   if(EXTI_GetITStatus(EXTI_Line4) != RESET)
   
4.   {
   
5.     /* Clear the EXTI line 0 pending bit */
   / B* O/ H+ b; H( `; U
6.     EXTI_ClearITPendingBit(EXTI_Line4);
   
7.         if(PauseFlag == 0)
   
8.         {
   ) {& l+ U, }' x9 P: P3 R
9.             ExtiCnt++;
   8 f, Z' b: t" J6 G! H3 \( s
10. 
    
11.         }
    ' I2 i( `; U" J/ |3 `  M
12.   }
    , [2 v& E+ L$ Z( a) }0 a
13.   if(EXTI_GetITStatus(EXTI_Line5) != RESET)
    . l+ y2 j1 O6 P
14.   {
    . u: g! [/ p% C$ E; H+ E' P
15.     /* Clear the EXTI line 0 pending bit */
    , N: ~1 w3 o0 w3 A' P+ N
16.     EXTI_ClearITPendingBit(EXTI_Line5);
    " U- u- e  x- Y3 d
17.         if(PauseFlag == 0)
    ) O$ K8 S: N# h/ c: m
18.         {
    
19.             ExtiCnt++;
    
20. 
    % @: o" U+ c' f$ o' n5 [; P
21.         }
    . k" @9 `& B0 t! B" T: Y$ L+ ^
22.   }
    . q7 T9 K, t$ c
23. }

复制代码

% ~( X) T! ~! Q1 _; i