[STM32F103]定时器中断

时间:2021-03-08 23:33:29

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:

 1 //Tout(溢出时间)=(ARR+1)(PSC+1)/Tclk
 2 //500ms -> (4999+1)( 7199+1)/72000000 = 0.5s = 500ms
 3  void TIM3_Int_Init(u16 arr,u16 psc)
 4 {
 5      TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
 6     NVIC_InitTypeDef NVIC_InitStructure;
 7 
 8     RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能
 9     
10     //定时器TIM3初始化
11     TIM_TimeBaseStructure.TIM_Period = arr; //设置更新装载值
12     TIM_TimeBaseStructure.TIM_Prescaler =psc;//设置预分频值
13     TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割
14     TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
15     TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); 
16  
17     TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //允许更新中断
18 
19     //中断优先级NVIC设置
20     NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断
21     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;  //0抢占优先级
22     NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3;  //响应优先级
23     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道势能
24     NVIC_Init(&NVIC_InitStructure);  //初始化NVIC寄存器
25 
26 
27     TIM_Cmd(TIM3, ENABLE);  //使能TIM                     
28 }
29 //定时器3中断服务程序
30 void TIM3_IRQHandler(void)
31 {
32     if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)  //检查是否更新中断
33         {
34         TIM_ClearITPendingBit(TIM3, TIM_IT_Update  );  //清楚更新中断 
35         LED1=!LED1;
36         }
37 }
38 int main(void)
39  { 
40     delay_init();  
41     NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);//抢占和响应优先级的范围0~3
42     uart_init(115200);
43      LED_Init();
44     TIM3_Int_Init(4999,7199); 
45        while(1)
46     {
47         LED0=!LED0;
48         delay_ms(200);           
49     }     
50 }