[STM32F103]定时器中断

l 使能定时器时钟。

　　RCC_APB1PeriphClockCmd();

l 初始化定时器，配置ARR,PSC。

　　TIM_TimeBaseInit();

l 开启定时器中断，配置NVIC。

　　void TIM_ITConfig();

　　NVIC_Init();

l 使能定时器。

　　TIM_Cmd();

l 编写中断服务函数。

　　TIMx_IRQHandler();

 

l 源代码：

//Tout（溢出时间）=（ARR+1)(PSC+1)/Tclk
//500ms -> (4999+1)( 7199+1)/72000000 = 0.5s = 500ms
 void TIM3_Int_Init(u16 arr,u16 psc)
{
     TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
    NVIC_InitTypeDef NVIC_InitStructure;

    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能
    
    //定时器TIM3初始化
    TIM_TimeBaseStructure.TIM_Period = arr; //设置更新装载值
    TIM_TimeBaseStructure.TIM_Prescaler =psc;//设置预分频值
    TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
    TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); 
 
    TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //允许更新中断

    //中断优先级NVIC设置
    NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断
    NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //0抢占优先级
    NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;  //响应优先级
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道势能
    NVIC_Init(&NVIC_InitStructure);  //初始化NVIC寄存器


    TIM_Cmd(TIM3, ENABLE);  //使能TIM                     
}
//定时器3中断服务程序
void TIM3_IRQHandler(void)
{
    if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)  //检查是否更新中断
        {
        TIM_ClearITPendingBit(TIM3, TIM_IT_Update  );  //清楚更新中断 
        LED1=!LED1;
        }
}
int main(void)
 { 
    delay_init();  
    NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//抢占和响应优先级的范围0~3
    uart_init(115200);
     LED_Init();
    TIM3_Int_Init(4999,7199); 
       while(1)
    {
        LED0=!LED0;
        delay_ms(200);           
    }     
}