/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    Examples_LL/TIM/TIM_InputCapture_Init/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to use a timer instance in input 
  *          capture mode using the STM32WLxx TIM LL API.
  *          Peripheral initialization done using LL unitary services functions.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2020 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* Number of frequencies */
#define TIM_FREQUENCIES_NB 10
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */
/* Frequency table */
static uint32_t aFrequency[TIM_FREQUENCIES_NB] = {
  2000,   /*  2 kHz */
  4000,   /*  4 kHz */
  6000,   /*  6 kHz */
  8000,   /*  8 kHz */
  10000,  /* 10 kHz */
  12000,  /* 12 kHz */
  14000,  /* 14 kHz */
  16000,  /* 16 kHz */
  18000,  /* 18 kHz */
  20000,  /* 20 kHz */
};

/* Frequency index */
static uint8_t iFrequency = 0;

/* Measured frequency */
__IO uint32_t uwMeasuredFrequency = 0;

/* TIM2 Clock */
static uint32_t TimOutClock = 1;
static uint32_t tim_period = 0;
static uint32_t tim_pulse_value = 0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM1_Init(void);
static void MX_TIM2_Init(void);
/* USER CODE BEGIN PFP */
__STATIC_INLINE void Configure_Frequency(uint32_t Frequency);
__STATIC_INLINE void LED_Blinking(uint32_t Period);
/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */

  /* System interrupt init*/
  NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* Set the auto-reload value to have a counter frequency of 2 kHz           */
  /* TIM2CLK = SystemCoreClock / (APB prescaler & multiplier)                 */
  TimOutClock = SystemCoreClock/(2/2);
  /* TIM2 counter frequency = TimOutClock / (ARR + 1)                   */
  tim_period = __LL_TIM_CALC_ARR(TimOutClock, 0, aFrequency[0]);

  /* Set compare value to half of the counter period (50% duty cycle )*/
  tim_pulse_value = tim_period / 2;

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_TIM1_Init();
  MX_TIM2_Init();
  /* USER CODE BEGIN 2 */

  /**************************/
  /* TIM1 interrupts set-up */
  /**************************/
  /* Enable the capture/compare interrupt for channel 1 */
  LL_TIM_EnableIT_CC1(TIM1);
  
  /***********************/
  /* Start input capture */
  /***********************/
  /* Enable output channel 1 */
  LL_TIM_CC_EnableChannel(TIM1, LL_TIM_CHANNEL_CH1);
    
  /* Enable counter */
  LL_TIM_EnableCounter(TIM1);

  /* Enable TIM2_CCR1 register preload. Read/Write operations access the      */
  /* preload register. TIM2_CCR1 preload value is loaded in the active        */
  /* at each update event.                                                    */
  LL_TIM_OC_EnablePreload(TIM2, LL_TIM_CHANNEL_CH1);
  
  /**********************************/
  /* Start output signal generation */
  /**********************************/
  /* Enable output channel 1 */
  LL_TIM_CC_EnableChannel(TIM2, LL_TIM_CHANNEL_CH1);
    
  /* Enable counter */
  LL_TIM_EnableCounter(TIM2);

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_2);
  while(LL_FLASH_GetLatency() != LL_FLASH_LATENCY_2)
  {
  }

  LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
  LL_RCC_MSI_Enable();

   /* Wait till MSI is ready */
  while(LL_RCC_MSI_IsReady() != 1)
  {
  }

  LL_RCC_MSI_EnableRangeSelection();
  LL_RCC_MSI_SetRange(LL_RCC_MSIRANGE_11);
  LL_RCC_MSI_SetCalibTrimming(0);
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_MSI);

   /* Wait till System clock is ready */
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_MSI)
  {
  }

  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAHB3Prescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1);

  LL_Init1msTick(48000000);

  /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(48000000);
}

/**
  * @brief TIM1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_TIM1_Init(void)
{

  /* USER CODE BEGIN TIM1_Init 0 */

  /* USER CODE END TIM1_Init 0 */

  LL_TIM_InitTypeDef TIM_InitStruct = {0};

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* Peripheral clock enable */
  LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_TIM1);

  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);
  /**TIM1 GPIO Configuration
  PA8   ------> TIM1_CH1
  */
  GPIO_InitStruct.Pin = LL_GPIO_PIN_8;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_1;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* TIM1 interrupt Init */
  NVIC_SetPriority(TIM1_CC_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(TIM1_CC_IRQn);

  /* USER CODE BEGIN TIM1_Init 1 */

  /* USER CODE END TIM1_Init 1 */
  TIM_InitStruct.Prescaler = 0;
  TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
  TIM_InitStruct.Autoreload = 0xFFFF;
  TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
  TIM_InitStruct.RepetitionCounter = 0;
  LL_TIM_Init(TIM1, &TIM_InitStruct);
  LL_TIM_DisableARRPreload(TIM1);
  LL_TIM_SetTriggerOutput(TIM1, LL_TIM_TRGO_RESET);
  LL_TIM_SetTriggerOutput2(TIM1, LL_TIM_TRGO2_RESET);
  LL_TIM_DisableMasterSlaveMode(TIM1);
  LL_TIM_IC_SetActiveInput(TIM1, LL_TIM_CHANNEL_CH1, LL_TIM_ACTIVEINPUT_DIRECTTI);
  LL_TIM_IC_SetPrescaler(TIM1, LL_TIM_CHANNEL_CH1, LL_TIM_ICPSC_DIV1);
  LL_TIM_IC_SetFilter(TIM1, LL_TIM_CHANNEL_CH1, LL_TIM_IC_FILTER_FDIV1);
  LL_TIM_IC_SetPolarity(TIM1, LL_TIM_CHANNEL_CH1, LL_TIM_IC_POLARITY_RISING);
  /* USER CODE BEGIN TIM1_Init 2 */

  /* USER CODE END TIM1_Init 2 */

}

/**
  * @brief TIM2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_TIM2_Init(void)
{

  /* USER CODE BEGIN TIM2_Init 0 */

  /* USER CODE END TIM2_Init 0 */

  LL_TIM_InitTypeDef TIM_InitStruct = {0};
  LL_TIM_OC_InitTypeDef TIM_OC_InitStruct = {0};

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* Peripheral clock enable */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_TIM2);

  /* USER CODE BEGIN TIM2_Init 1 */

  /* USER CODE END TIM2_Init 1 */
  TIM_InitStruct.Prescaler = 0;
  TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
  TIM_InitStruct.Autoreload = tim_period;
  TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
  LL_TIM_Init(TIM2, &TIM_InitStruct);
  LL_TIM_EnableARRPreload(TIM2);
  LL_TIM_OC_EnablePreload(TIM2, LL_TIM_CHANNEL_CH1);
  TIM_OC_InitStruct.OCMode = LL_TIM_OCMODE_PWM1;
  TIM_OC_InitStruct.OCState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.OCNState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.CompareValue = tim_pulse_value;
  TIM_OC_InitStruct.OCPolarity = LL_TIM_OCPOLARITY_HIGH;
  LL_TIM_OC_Init(TIM2, LL_TIM_CHANNEL_CH1, &TIM_OC_InitStruct);
  LL_TIM_OC_DisableFast(TIM2, LL_TIM_CHANNEL_CH1);
  LL_TIM_SetTriggerOutput(TIM2, LL_TIM_TRGO_RESET);
  LL_TIM_DisableMasterSlaveMode(TIM2);
  /* USER CODE BEGIN TIM2_Init 2 */

  /* USER CODE END TIM2_Init 2 */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);
  /**TIM2 GPIO Configuration
  PA5   ------> TIM2_CH1
  */
  GPIO_InitStruct.Pin = TIM2_CH1_Pin;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_1;
  LL_GPIO_Init(TIM2_CH1_GPIO_Port, &GPIO_InitStruct);

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  LL_EXTI_InitTypeDef EXTI_InitStruct = {0};
  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOB);
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);

  /**/
  LL_GPIO_ResetOutputPin(LED2_GPIO_Port, LED2_Pin);

  /**/
  GPIO_InitStruct.Pin = LED2_Pin;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_OUTPUT;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  LL_GPIO_Init(LED2_GPIO_Port, &GPIO_InitStruct);

  /**/
  LL_SYSCFG_SetEXTISource(LL_SYSCFG_EXTI_PORTA, LL_SYSCFG_EXTI_LINE0);

  /**/
  EXTI_InitStruct.Line_0_31 = LL_EXTI_LINE_0;
  EXTI_InitStruct.Line_32_63 = LL_EXTI_LINE_NONE;
  EXTI_InitStruct.LineCommand = ENABLE;
  EXTI_InitStruct.Mode = LL_EXTI_MODE_IT;
  EXTI_InitStruct.Trigger = LL_EXTI_TRIGGER_FALLING;
  LL_EXTI_Init(&EXTI_InitStruct);

  /**/
  LL_GPIO_SetPinPull(USER_BUTTON_GPIO_Port, USER_BUTTON_Pin, LL_GPIO_PULL_UP);

  /**/
  LL_GPIO_SetPinMode(USER_BUTTON_GPIO_Port, USER_BUTTON_Pin, LL_GPIO_MODE_INPUT);

  /* EXTI interrupt init*/
  NVIC_SetPriority(EXTI0_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(EXTI0_IRQn);

}

/* USER CODE BEGIN 4 */

/**
  * @brief  Changes the frequency of the PWM signal.
  * @note this function is executed within the CC1 interrupt service
  *       routine context.
  * @param  Requested frequency
  * @retval None
  */
__STATIC_INLINE void Configure_Frequency(uint32_t Frequency)
{
  /* Set the auto-reload value to have the requested frequency */
  /* Frequency = TIM2CLK / (ARR + 1)                   */
  LL_TIM_SetAutoReload(TIM2, __LL_TIM_CALC_ARR(TimOutClock, LL_TIM_GetPrescaler(TIM2), Frequency));
 
  /* Set compare value to half of the counter period (50% duty cycle )*/
  LL_TIM_OC_SetCompareCH1(TIM2, (LL_TIM_GetAutoReload(TIM2) / 2));
}

/**
  * @brief  Set LED2 to Blinking mode for an infinite loop (toggle period based on value provided as input parameter).
  * @param  Period : Period of time (in ms) between each toggling of LED
  *   This parameter can be user defined values. Pre-defined values used in that example are :
  *     @arg LED_BLINK_FAST : Fast Blinking
  *     @arg LED_BLINK_SLOW : Slow Blinking
  *     @arg LED_BLINK_ERROR : Error specific Blinking
  * @retval None
  */
__STATIC_INLINE void LED_Blinking(uint32_t Period)
{
  /* Toggle IO in an infinite loop */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_Port, LED2_Pin);  
    LL_mDelay(Period);
  }
}

/******************************************************************************/
/*   USER IRQ HANDLER TREATMENT                                               */
/******************************************************************************/
/**
  * @brief  User button interrupt processing
  * @note   When the user key button is pressed the frequency of the  
  *         PWM signal generated by TIM2 is updated. 
  * @param  None
  * @retval None
  */
void UserButton_Callback(void)
{
  /* Set new PWM signal frequency */
  iFrequency = (iFrequency + 1) % TIM_FREQUENCIES_NB;

  /* Change PWM signal frequency */
  Configure_Frequency(aFrequency[iFrequency]);
}

/**
  * @brief  Timer capture/compare interrupt processing
  * @note TIM1 input capture module is used to capture the value of the counter
  *       after a transition is detected by the corresponding input channel.
  * @param  None
  * @retval None
  */
void TimerCaptureCompare_Callback(void)
{
  /* Capture index */
  static uint16_t uhCaptureIndex = 0;
  
  /* Captured Values */
  static uint32_t uwICValue1 = 0;
  static uint32_t uwICValue2 = 0;
  static uint32_t uwDiffCapture = 0;
  
  uint32_t TIM1CLK;
  uint32_t PSC;
  uint32_t IC1PSC;
  uint32_t IC1Polarity;
  
  if(uhCaptureIndex == 0)
  {
    /* Get the 1st Input Capture value */
    uwICValue1 = LL_TIM_IC_GetCaptureCH1(TIM1);
    uhCaptureIndex = 1;
  }
  else if(uhCaptureIndex == 1)
  {
    /* Get the 2nd Input Capture value */
    uwICValue2 = LL_TIM_IC_GetCaptureCH1(TIM1); 
    
    /* Capture computation */
    if (uwICValue2 > uwICValue1)
    {
      uwDiffCapture = (uwICValue2 - uwICValue1); 
    }
    else if (uwICValue2 < uwICValue1)
    {
      uwDiffCapture = ((TIM1_ARR_MAX - uwICValue1) + uwICValue2) + 1; 
    }
    else
    {
      /* If capture values are equal, we have reached the limit of frequency  */
      /* measures.                                                            */
      LED_Blinking(LED_BLINK_ERROR);
    }
    
    /* The signal frequency is calculated as follows:                         */      
    /* Frequency = (TIM1*IC1PSC) / (Capture*(PSC+1)*IC1Polarity)           */
    /* where:                                                                 */                                                          
    /*  Capture is the difference between two consecutive captures            */
    /*  TIM1CLK is the timer counter clock frequency                           */
    /*  PSC is the timer prescaler value                                      */
    /*  IC1PSC is the input capture prescaler value                           */
    /*  IC1Polarity value depends on the capture sensitivity:                 */
    /*    1 if the input is sensitive to rising or falling edges              */
    /*    2 if the input is sensitive to both rising and falling edges        */
    
    /* Retrieve actual TIM1 counter clock frequency */
    TIM1CLK = SystemCoreClock;
    
    /* Retrieve actual TIM1 prescaler value */
    PSC = LL_TIM_GetPrescaler(TIM1);
    
    /* Retrieve actual IC1 prescaler ratio */
    IC1PSC = __LL_TIM_GET_ICPSC_RATIO(LL_TIM_IC_GetPrescaler(TIM1, LL_TIM_CHANNEL_CH1));
   
    /* Retrieve actual IC1 polarity setting */
    if (LL_TIM_IC_GetPolarity(TIM1, LL_TIM_CHANNEL_CH1) == LL_TIM_IC_POLARITY_BOTHEDGE)
      IC1Polarity = 2;
    else
      IC1Polarity = 1;
    
    /* Calculate input signal frequency */
    uwMeasuredFrequency = (TIM1CLK *IC1PSC) / (uwDiffCapture*(PSC+1)*IC1Polarity);
    
    /* reset capture index */
    uhCaptureIndex = 0;    
  }
}

/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
 
  /* USER CODE END Error_Handler_Debug */
}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* USER CODE BEGIN 6 */
  /* User can add his own implementation to report the file name and line number,
     tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* Infinite loop */
  while (1)
  {
  }

  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
