Timer capture driver for smart learning air conditioning project based on STM32

/*************************************************************************************************************************

* Function: TIM3.C

* Function: Infrared signal capture and transmission

* Parameters: None

* Return: None

* Dependency: underlying read and write functions

*************************************************************************************************************************/ 

voidIRDA_GPIO_Init(void)

{

 GPIO_InitTypeDef  GPIO_InitStructure;

//LED1 LED2

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //Enable PA, PD port clock

 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); //Enable PA, PD port clock

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11|GPIO_Pin_12; //

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP; //Push-pull output

 GPIO_InitStructure.GPIO_Speed ​​= GPIO_Speed_50MHz; //IO port speed is 50MHz

 GPIO_Init(GPIOA, &GPIO_InitStructure); //Initialize GPIOA according to the set parameters.8

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //PA6 clears the previous settings  

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

 GPIO_Init(GPIOA, &GPIO_InitStructure);

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5; //PA6 clears the previous settings  

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

 GPIO_Init(GPIOA, &GPIO_InitStructure);

 GPIO_SetBits(GPIOA,GPIO_Pin_5); //PA.8 output high

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10 | GPIO_Pin_11; //PA6 clears previous settings  

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

 GPIO_Init(GPIOB, &GPIO_InitStructure);

//Watchdog SP706 input pin PA7

 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7; //PA7 clears the previous settings  

 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

 GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

 GPIO_Init(GPIOA, &GPIO_InitStructure);

}

void TIM3_Int_Init(u16 arr,u16 psc)

{

  TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;

  TIM_ICInitTypeDef  TIM_ICInitStructure;

NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //Clock enable

TIM_TimeBaseStructure.TIM_Period = arr; //Set the value of the auto-reload register period to count to 5000 for 500ms before the next update event

TIM_TimeBaseStructure.TIM_Prescaler =psc; //Set the prescaler value used as the TIMx clock frequency divisor 10Khz counting frequency  

TIM_TimeBaseStructure.TIM_ClockDivision = 0; //Set clock division: TDTS = Tck_tim

TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM up counting mode

TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //Initialize the time base unit of TIMx according to the parameters specified in TIM_TimeBaseInitStruct

  TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;

  TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Falling;

  TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;

  TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;

  TIM_ICInitStructure.TIM_ICFilter = 0x0;

  TIM_ICInit(TIM3, &TIM_ICInitStructure);

NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;  //TIM3中断

NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //Preempt priority level 0

NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //From priority level 3

NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ channel is enabled

NVIC_Init(&NVIC_InitStructure); //Initialize peripheral NVIC registers according to the parameters specified in NVIC_InitStruct

TIM_ITConfig(TIM3,TIM_IT_CC1,DISABLE); //Do not allow CC1IE to capture interrupts

TIM_ITConfig(TIM3,TIM_IT_Update,DISABLE);//Update interrupt is not allowed

TIM_Cmd(TIM3,DISABLE); //Enable timer 3

}

void TIM_Polarityset(u8 Polarity)

{

 if(Polarity == 0) TIM3->CCER &= ~(1<<1); //Rise

 else TIM3->CCER |= 1<<1; //Decline

}

void TIM3_IRQHandler(void)   //TIM3中断

{

 if(TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET) //Check whether the specified TIM interrupt occurs: TIM interrupt source 

 {

TIM_ClearITPendingBit(TIM3,TIM_IT_Update ); // Clear TIMx interrupt pending bit: TIM interrupt source 

  switch(Timer3)

  {

   case 0:

   {

    Timer3++;

    if(u8Lev == 0x0) GPIO_SetBits(GPIOA,GPIO_Pin_5);

    else GPIO_ResetBits(GPIOA,GPIO_Pin_5);

    break;

   }

   case 1:

   {

    Timer3++;

    GPIO_SetBits(GPIOA,GPIO_Pin_5);

    break;

   }

   case 2:

   {

    Timer3 = 0;

    Timer_PWM++;

    if(Timer_PWM >= Capture)

    {

     Capture =  u16P[u16Pcn++];

     if(Capture == 0xffff) // Output ends

     {

      TIM_ITConfig(TIM3,TIM_IT_Update,DISABLE);

      TIM_Cmd(TIM3,DISABLE);

      GPIO_SetBits(GPIOA,GPIO_Pin_5);

irad_launch = 1;

      u8FSMirda = IRDA_FSM_DILE;

     }

     else

     {

      u8Lev = ~u8Lev;

      Timer_PWM = 0;

     } 

    }

    break;

   }

   default:

   {

    Timer3 = 0;

   } 

  }

 }

 if(TIM_GetITStatus(TIM3, TIM_IT_CC1) == SET) 

  {

    //TIM_ICInitTypeDef  TIM_ICInitStructure;

    /* Clear TIM3 Capture compare interrupt pending bit */

    TIM_ClearITPendingBit(TIM3, TIM_IT_CC1);

    u8Timerirda = 0;

    if(CaptureNumber == 0)

    {

      /* Get the Input Capture value */

      IC3ReadValue1 = TIM_GetCapture1(TIM3);

      CaptureNumber = 1;

      u8Lev = 0xff;

    }

    else if(CaptureNumber == 1)

    {

      /* Get the Input Capture value */

      IC3ReadValue2 = TIM_GetCapture1(TIM3); 

      /* Capture computation */

      if (IC3ReadValue2 > IC3ReadValue1)

      {

        Capture = (IC3ReadValue2 - IC3ReadValue1); 

      }

      else

      {

        Capture = ((0xFFFF - IC3ReadValue1) + IC3ReadValue2); 

      }

      u16P[u16Pcn++] = Capture;

      IC3ReadValue1 = IC3ReadValue2;

      /* Frequency computation */ 

      //TIM3Freq = (uint32_t) SystemCoreClock / Capture;

      //CaptureNumber = 0;

    }

  u8Lev = ~u8Lev;  

  TIM_Polarityset(u8Lev);  

  }

}