标题: stm32通过tim定时器中断,进行周期性任务 [打印本页]

作者: l雷厉风行l    时间: 2019-12-13 15:38
标题: stm32通过tim定时器中断,进行周期性任务
//下面是定时器TIM3_CH3的初始化,如果需要更换或添加TIM的其他通道,直接修改管脚和下面的注释即可

void TIM3_Cap_Init(u16 arr,u16 psc)
{
    GPIO_InitTypeDef GPIO_InitStructure;
    NVIC_InitTypeDef NVIC_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;
   
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能 TIM3 时钟
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); //使能 GPIOB 时钟
   
    //TIM3_CH3-->PB0
      GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
      GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
      GPIO_Init(GPIOB , &GPIO_InitStructure);
   
/* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 65535;         //这里必须是65535
  TIM_TimeBaseStructure.TIM_Prescaler = 71;            //72(71+1)分频,也就是1MHz(主频72MHz)
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;      //
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //向上计数模式

  TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);          //初始化TIM3

  /* Output Compare Toggle Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;    //输出比较翻转模式,产生中断后,输出管脚电平翻转,可设置成其他模式,百度一下就好
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;         //输出为负逻辑
  /*TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;   //使能通道1
  TIM_OCInitStructure.TIM_Pulse = CCR1_Val;                       //待装入输出比较寄存器中的脉冲值,也就是计时器达到多少后产生中断      
  TIM_OC1Init(TIM3, &TIM_OCInitStructure);        //写入配置
  TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Disable);*/          //使能或者失能TIMx在CCR1上的预装载寄存器

  /* Output Compare Toggle Mode configuration: Channel2 */
  /*TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR2_Val;
  TIM_OC2Init(TIM3, &TIM_OCInitStructure);
  TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Disable);*/

  /* Output Compare Toggle Mode configuration: Channel3 */
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = PPM_IN[ppm_i];
  TIM_OC3Init(TIM3, &TIM_OCInitStructure);
  TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Disable);

  /* Output Compare Toggle Mode configuration: Channel4 */
  /*TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = CCR4_Val;
  TIM_OC4Init(TIM3, &TIM_OCInitStructure);
  TIM_OC4PreloadConfig(TIM3, TIM_OCPreload_Disable);*/
   
    //中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn; //TIM3 中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级 2 级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //从优先级 0 级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ 通道被使能
NVIC_Init(&NVIC_InitStructure); //初始化外设 NVIC 寄存器
TIM_ITConfig(TIM3,TIM_IT_CC3,ENABLE);

  /* TIM enable counter */
  TIM_Cmd(TIM3, ENABLE);      //开启计数器

  /* TIM IT enable */                //TIM1中断源设置,开启相应通道的捕捉比较中断
  //TIM_ITConfig(TIM3, TIM_IT_CC1 | TIM_IT_CC2 | TIM_IT_CC3 | TIM_IT_CC4, ENABLE);
    //TIM_ITConfig(TIM3, TIM_IT_CC3, ENABLE);

}
//定时器 3 中断服务程序
void TIM3_IRQHandler(void)
{
    /*if (TIM_GetITStatus(TIM3, TIM_IT_CC3) != RESET)      //检查指定的TIM(3通道)中断发生与否
  {
    TIM_ClearITPendingBit(TIM3, TIM_IT_CC3 );          //清除TIMx的中断待处理位
    capture = TIM_GetCapture3(TIM3);                   //获得输入捕获值,即计数器中的计数值
    TIM_SetCompare3(TIM3, capture + 500 );        //将计数值加上翻转的脉冲值写入输出比较寄存器中,以保证下一个TIM事件,可以实现周期性产生中断
  }*/

     if (TIM_GetITStatus(TIM3, TIM_IT_CC3) != RESET)//(tim3,3通道),这部分是我工程中用到的,也可以改成上面的内容,实现周期性中断
  {    //outdata();
    TIM_ClearITPendingBit(TIM3, TIM_IT_CC3);
    capture = TIM_GetCapture3(TIM3);
        if(ppm_i==nPPM*2+1){
            ppm_i=0;
        }else{
            ppm_i++;
        }
    TIM_SetCompare3(TIM3, capture + PPM_IN[ppm_i]);
  }
}


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作者: 心瘾难戒    时间: 2019-12-13 16:51
感谢,对我帮助很大,挺你




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