[stm32] 中断

 #include  "stm32f10x.h"
 #include  "stm32f10x_tim.h"
 #include  "misc.h"
 #include  "stm32f10x_gpio.h"

 unsigned int CCR2_Val=;
 extern void time_ini(void);
 unsigned int capture1=;
 TIM_TimeBaseInitTypeDef  TIM3_TimeBaseStructure;
 TIM_OCInitTypeDef  TIM3_OCInitStructure;
 TIM_BDTRInitTypeDef TIM3_BDTRInitStructure;

 void time_ini(void){
   GPIO_InitTypeDef GPIO_InitStructure;
   RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);            //定时器3 时钟使能

   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;                        //PB5复用为TIM3的通道2
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
   GPIO_Init(GPIOB, &GPIO_InitStructure);

   /* TIM3局部复用功能开启     在TIM3的局部复用开启时，PB5会被复用为TIM3_CH2*/
   GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3 , ENABLE);    

   /* Time Base configuration */
   /*-------------------------------------------------------------------
   TIM3CLK=72MHz  预分频系数Prescaler=63 经过分频 定时器时钟为1.125MHz
   捕获/比较寄存器2 TIM3_CCR2= CCR2_Val
   2通道产生的更新频率是=1.125MHz/CCR2_Val=25Hz

   -------------------------------------------------------------------*/
   TIM3_TimeBaseStructure.TIM_Prescaler = ;                        //预分频器TIM3_PSC=630
   TIM3_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;        //计数器向上计数模式 TIM3_CR1[4]=0
   TIM3_TimeBaseStructure.TIM_Period =0xffff;                        //自动重装载寄存器TIM3_APR
   TIM3_TimeBaseStructure.TIM_ClockDivision = 0x0;                    //时钟分频因子 TIM3_CR1[9:8]=00

   TIM_TimeBaseInit(TIM3,&TIM3_TimeBaseStructure);                    //写TIM3各寄存器参数

   TIM3_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle ;                //TIM3_CCMR1[14:12]=011  翻转 当TIM3_CCR2=TIM3_CNT时，翻转OC2REF的电平
   TIM3_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;    //输入/捕获2输出允许  OC2信号输出到对应的输出引脚PB5
   TIM3_OCInitStructure.TIM_Pulse =CCR2_Val;                            //若CC1通道配置为输出：CCR2是装入当前捕获/比较2 TIM3_CCR2寄存器的值（预装载值）。
                                                                       //当前捕获/比较寄存器包含了与计数器TIM3_CNT比较的值，并且在OC端口上输出信号
   TIM3_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;            //输出极性  低电平有效 TIM3_CCER[5]=1;

   TIM_OC2Init(TIM3, &TIM3_OCInitStructure);
   TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Disable);                //TIM3_CCMR1[1]=0  禁止TIM3_CCR2寄存器的预装载功能，可随时写入TIM3_CCR2
                                                                     //且新值马上起作用

    TIM_Cmd(TIM3,ENABLE);                                            //启动定时器3 TIM3_CR1[0]=1;
    TIM_ITConfig(TIM3,TIM_IT_CC2,ENABLE);                             //TIM3_DIER[2]=1  允许捕获/比较2中断
 }

 void RCC_Configuration(void){

   SystemInit();
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC
                           | RCC_APB2Periph_GPIOD| RCC_APB2Periph_GPIOE , ENABLE);
 }

 void NVIC_Configuration(void)
 {
   NVIC_InitTypeDef NVIC_InitStructure;
   NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

   NVIC_InitStructure.NVIC_IRQChannel =TIM3_IRQn ;               //配置定时器中断
   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = ;
   NVIC_InitStructure.NVIC_IRQChannelSubPriority = ;
   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
   NVIC_Init(&NVIC_InitStructure);
 }

 int main(void)
 {
   RCC_Configuration();                        //系统时钟设置及外设时钟使能
   NVIC_Configuration();                         //中断源配置
   time_ini();                                 //定时器3的初始化
   while();
 }

 void TIM3_IRQHandler(void){ 

  if (TIM_GetITStatus(TIM3, TIM_IT_CC2) != RESET)        //判断状态寄存器 TIM3_SR[2] 是否发生了捕获/比较2 中断
   {
     TIM_ClearITPendingBit(TIM3, TIM_IT_CC2);            //软件清除状态寄存器 TIM3_SR[2] 捕获/比较2 中断中断标志

     capture1 = TIM_GetCapture2(TIM3);                    //获取TIM3_CCR2的预装值
     TIM_SetCompare2(TIM3, capture1+ CCR2_Val);            //和CCR2_Val累加后装入TIM3_CCR2     这是为了配合计数器值的递增。以在下一次作出比较。

   }

 }