STM32:TIMER PWM 输入检测

PWM输入检测是输入捕获的一个特例，可以测量频率与占空比

与输入捕获不同的是PWM输入模式会将同一个输入信号（TI1或TI2）连接到两个捕获装置（IC1和IC2）。这两个捕获装置一个捕获上升沿一个捕获下降沿。TI1FP1、TI2FP2它们中的一个被选择为触发输入且从模式控制器被配置为复位模式。

注意：只有TI1FP1和TI2FP2连到了从模式控制器，所以PWM输入模式只能使用TIMx_CH1 /TIMx_CH2信号。

 //Timer4 CH2测周期，CH1测占空比，PB7引脚来输入
 //这个捕捉的周期的范围是1-65535us，如果需要测更高频率的话更改里面的两种方式：
 //1,TIM_TimeBaseStructure.TIM_Prescaler =(72-1);更改分配系数调整精度
 //溢出计数也可以使用
 void TIM4_CH2_CH1_PB7_PWMInPut_Init(void)
 {  

     TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
     NVIC_InitTypeDef         NVIC_InitStructure;
     TIM_ICInitTypeDef        TIM4_ICInitStructure;
     GPIO_InitTypeDef         GPIO_InitStructure;

     RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);     //Open TIM4 clock
     RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);  //open gpioB clock

     GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;                               //GPIO??
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
     GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
     GPIO_Init(GPIOB, &GPIO_InitStructure);

     TIM_TimeBaseStructure.TIM_Period = 0xffff; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值
     TIM_TimeBaseStructure.TIM_Prescaler =(-); //设置用来作为TIMx时钟频率除数的预分频值
     TIM_TimeBaseStructure.TIM_ClockDivision = ; //设置时钟分割:TDTS = Tck_tim
     TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
     TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

     /*配置中断优先级*/
     NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn;
     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = ;
     NVIC_InitStructure.NVIC_IRQChannelSubPriority = ;
     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
     NVIC_Init(&NVIC_InitStructure);

     TIM4_ICInitStructure.TIM_Channel = TIM_Channel_2;
     TIM4_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
     TIM4_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
     TIM4_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
     TIM4_ICInitStructure.TIM_ICFilter = 0x0;
     TIM_PWMIConfig(TIM4, &TIM4_ICInitStructure);     //PWM输入配置    

     TIM_SelectInputTrigger(TIM4, TIM_TS_TI2FP2);     //选择有效输入端
     TIM_SelectSlaveMode(TIM4, TIM_SlaveMode_Reset);  //配置为主从复位模式
     TIM_SelectMasterSlaveMode(TIM4, TIM_MasterSlaveMode_Enable);
     TIM_ITConfig(TIM4, TIM_IT_CC2|TIM_IT_Update, ENABLE);          //中断配置

     TIM_ClearITPendingBit(TIM4, TIM_IT_CC2|TIM_IT_Update); //清除中断标志位
     TIM_Cmd(TIM4, ENABLE);
 }

TIM4_CH2_CH1_PB7_PWMInPut_Init

 void TIM4_IRQHandler(void)
 {

     if(TIM_GetITStatus(TIM4,TIM_IT_Update)!=RESET)
     {
 //        LED1_Toggle();
         TIM_ClearITPendingBit(TIM4,TIM_IT_Update);
     }

     if(TIM_GetITStatus(TIM4,TIM_IT_CC1)!=RESET)
     {

         TIM_ClearITPendingBit(TIM4,TIM_IT_CC1);
     }

     if(TIM_GetITStatus(TIM4,TIM_IT_CC2)!=RESET)
     {

          printf("TIM4 frequency=%d , duty=%d \r\n",(/TIM_GetCapture2(TIM4)),(*TIM_GetCapture1(TIM4)/TIM_GetCapture2(TIM4)));
         TIM_ClearITPendingBit(TIM4,TIM_IT_CC2);
     }

     if(TIM_GetITStatus(TIM4,TIM_IT_CC4)!=RESET)
     {
         TIM_ClearITPendingBit(TIM4,TIM_IT_CC4);
     }    

 }

TIM4_IRQHandler

注意，如果用CH2测量频率，CH1测量占空比的话，只需要设置CH2，开启CC2中断即可，测量频率的CHX设置为上升沿捕获，

设置函数为： TIM_PWMIConfig(TIM4, &TIM4_ICInitStructure);
而不是TIM_ICInit(TIM4, &TIM4_ICInitStructure);如果选择这个函数初始化的话还需要设置CH1。

同样如果是CH2测量频率的话TIM_TS_TI2FP2，TIM_SelectInputTrigger(TIM4, TIM_TS_TI2FP2);     //选择有效输入端

如果CH1测量频率则为TIM_TS_TI1FP1

下面是TIMER3 配置CH1频率，CH2占空比

 //Timer3 CH1测周期，CH2测占空比，PA6引脚来输入
 //这个捕捉的周期的范围是1-65535us，如果需要测更高频率的话更改里面的两种方式：
 //1,TIM_TimeBaseStructure.TIM_Prescaler =(72-1);更改分配系数调整精度
 //溢出计数也可以使用
 void TIM3_CH1_CH2_PA6_PWMInPut_Init(void)
 {  

     TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
     NVIC_InitTypeDef         NVIC_InitStructure;
     TIM_ICInitTypeDef        TIM3_ICInitStructure;
     GPIO_InitTypeDef         GPIO_InitStructure;

     RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);  //使能GPIOA时钟
     RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能

     GPIO_InitStructure.GPIO_Pin  = GPIO_Pin_6;  //PA0 清除之前设置
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
     GPIO_Init(GPIOA, &GPIO_InitStructure);
     GPIO_ResetBits(GPIOA,GPIO_Pin_6);

     TIM_TimeBaseStructure.TIM_Period = 0xffff; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值     计数到5000为500ms
     TIM_TimeBaseStructure.TIM_Prescaler =(-); //设置用来作为TIMx时钟频率除数的预分频值  1Mhz的计数频率
     TIM_TimeBaseStructure.TIM_ClockDivision = ; //设置时钟分割:TDTS = Tck_tim
     TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
     TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位

      //pwm输入模式ch1配置
     TIM3_ICInitStructure.TIM_Channel = TIM_Channel_1;      //选择输入端 IC1映射到TI1上
       TIM3_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;    //上升沿捕获
       TIM3_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上 //CC1S=01
       TIM3_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;     //配置输入分频,不分频
       TIM3_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
     TIM_PWMIConfig(TIM3, &TIM3_ICInitStructure);     //PWM输入配置
 //      TIM_ICInit(TIM3, &TIM3_ICInitStructure);

 //    //pwm输入模式ch2配置
 //    TIM3_ICInitStructure.TIM_Channel = TIM_Channel_2;     //选择输入端 IC2映射到TI1上
 //      TIM3_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling;    //下降沿捕获
 //      TIM3_ICInitStructure.TIM_ICSelection = TIM_ICSelection_IndirectTI; //映射到TI1上 //CC2S=10
 //      TIM3_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;     //配置输入分频,不分频
 //      TIM3_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
 //      TIM_ICInit(TIM3, &TIM3_ICInitStructure);

     TIM_SelectInputTrigger(TIM3, TIM_TS_TI1FP1);     //选择有效输入端
     TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset);  //配置为主从复位模式
     TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable);
     TIM_ITConfig(TIM3,TIM_IT_Update|TIM_IT_CC1,ENABLE ); //使能指定的TIM3中断,允许更新中断

     NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断
     NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = ;  //先占优先级0级
     NVIC_InitStructure.NVIC_IRQChannelSubPriority = ;  //从优先级3级
     NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
     NVIC_Init(&NVIC_InitStructure);  //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器

     TIM_Cmd(TIM3, ENABLE);  //使能TIMx外设
 }

TIM3_CH1_CH2_PA6_PWMInPut_Init

 void TIM3_IRQHandler(void)
 {

     if(TIM_GetITStatus(TIM3,TIM_IT_Update)!=RESET)
     {
         LED2_Toggle();
         TIM_ClearITPendingBit(TIM3,TIM_IT_Update);
     }

     if(TIM_GetITStatus(TIM3,TIM_IT_CC1)!=RESET)
     {
          printf("TIM3 frequency=%d , duty=%d \r\n",(/TIM_GetCapture1(TIM3)),(*TIM_GetCapture2(TIM3)/TIM_GetCapture1(TIM3)));
         TIM_ClearITPendingBit(TIM3,TIM_IT_CC1);
     }

     if(TIM_GetITStatus(TIM3,TIM_IT_CC2)!=RESET)
     {

         TIM_ClearITPendingBit(TIM3,TIM_IT_CC2);
     }

 }

TIM3_IRQHandler