/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @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 */
/* Measured pulse delay (in us) */
static __IO uint32_t uwMeasuredDelay;

/* Measured pulse length (in us) */
static __IO uint32_t uwMeasuredPulseLength;

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

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

/* USER CODE END PM */

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

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);
static void MX_TIM1_Init(void);
/* USER CODE BEGIN PFP */

/* 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 */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_TIM2_Init();
  MX_TIM1_Init();
  /* USER CODE BEGIN 2 */
  /* Enable capture/compare interrupt */
  LL_TIM_EnableIT_CC1(TIM1);

  /* Enable output channels */
  LL_TIM_CC_EnableChannel(TIM1, LL_TIM_CHANNEL_CH1);
  LL_TIM_CC_EnableChannel(TIM2, LL_TIM_CHANNEL_CH1);

  /* Force update generation */
  LL_TIM_GenerateEvent_UPDATE(TIM1);
  LL_TIM_GenerateEvent_UPDATE(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 */
  uint32_t Prescaler;
  uint32_t Period;
  uint32_t Pulse;

  /* USER CODE END TIM1_Init 0 */

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

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

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

  /* 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 */

  /* Set the TIM1 prescaler to get counter clock frequency at 10 MHz          */
  /* Set the capture/compare register to get a pulse delay of 50 us */
  /* Set the autoreload register to get a pulse length of 50 us */
  Prescaler = __LL_TIM_CALC_PSC(SystemCoreClock, 10000000);
  Period = __LL_TIM_CALC_PULSE(SystemCoreClock, Prescaler, 50, 50);
  Pulse = __LL_TIM_CALC_DELAY(SystemCoreClock, Prescaler, 50);

  /* USER CODE END TIM1_Init 1 */
  TIM_InitStruct.Prescaler = Prescaler;
  TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
  TIM_InitStruct.Autoreload = Period;
  TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
  TIM_InitStruct.RepetitionCounter = 0;
  LL_TIM_Init(TIM1, &TIM_InitStruct);
  LL_TIM_EnableARRPreload(TIM1);
  LL_TIM_OC_EnablePreload(TIM1, LL_TIM_CHANNEL_CH1);
  TIM_OC_InitStruct.OCMode = LL_TIM_OCMODE_PWM2;
  TIM_OC_InitStruct.OCState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.OCNState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.CompareValue = Pulse;
  TIM_OC_InitStruct.OCPolarity = LL_TIM_OCPOLARITY_HIGH;
  TIM_OC_InitStruct.OCNPolarity = LL_TIM_OCPOLARITY_HIGH;
  TIM_OC_InitStruct.OCIdleState = LL_TIM_OCIDLESTATE_LOW;
  TIM_OC_InitStruct.OCNIdleState = LL_TIM_OCIDLESTATE_LOW;
  LL_TIM_OC_Init(TIM1, LL_TIM_CHANNEL_CH1, &TIM_OC_InitStruct);
  LL_TIM_OC_DisableFast(TIM1, LL_TIM_CHANNEL_CH1);
  LL_TIM_SetOnePulseMode(TIM1, LL_TIM_ONEPULSEMODE_SINGLE);
  LL_TIM_SetTriggerOutput(TIM1, LL_TIM_TRGO_RESET);
  LL_TIM_SetTriggerOutput2(TIM1, LL_TIM_TRGO2_RESET);
  LL_TIM_DisableMasterSlaveMode(TIM1);
  TIM_BDTRInitStruct.OSSRState = LL_TIM_OSSR_DISABLE;
  TIM_BDTRInitStruct.OSSIState = LL_TIM_OSSI_DISABLE;
  TIM_BDTRInitStruct.LockLevel = LL_TIM_LOCKLEVEL_OFF;
  TIM_BDTRInitStruct.DeadTime = 0;
  TIM_BDTRInitStruct.BreakState = LL_TIM_BREAK_DISABLE;
  TIM_BDTRInitStruct.BreakPolarity = LL_TIM_BREAK_POLARITY_HIGH;
  TIM_BDTRInitStruct.BreakFilter = LL_TIM_BREAK_FILTER_FDIV1;
  TIM_BDTRInitStruct.BreakAFMode = LL_TIM_BREAK_AFMODE_INPUT;
  TIM_BDTRInitStruct.Break2State = LL_TIM_BREAK2_DISABLE;
  TIM_BDTRInitStruct.Break2Polarity = LL_TIM_BREAK2_POLARITY_HIGH;
  TIM_BDTRInitStruct.Break2Filter = LL_TIM_BREAK2_FILTER_FDIV1;
  TIM_BDTRInitStruct.Break2AFMode = LL_TIM_BREAK_AFMODE_INPUT;
  TIM_BDTRInitStruct.AutomaticOutput = LL_TIM_AUTOMATICOUTPUT_ENABLE;
  LL_TIM_BDTR_Init(TIM1, &TIM_BDTRInitStruct);
  /* USER CODE BEGIN TIM1_Init 2 */

  /* USER CODE END TIM1_Init 2 */
  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);

}

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

  /* USER CODE BEGIN TIM2_Init 0 */
  uint32_t tim_clk;
  uint32_t Prescaler;
  uint32_t Period;
  uint32_t Pulse;

  /* 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);

  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);
  /**TIM2 GPIO Configuration
  PA1   ------> TIM2_CH2
  */
  GPIO_InitStruct.Pin = LL_GPIO_PIN_1;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_VERY_HIGH;
  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);

  /* USER CODE BEGIN TIM2_Init 1 */

  /* In this example TIM2 input clock (TIM2CLK) is set to APB1 clock (PCLK1), */
  /* since APB1 pre-scaler is equal to 1.                                     */
  /*    TIM2CLK = PCLK1                                                       */
  /*    PCLK1 = HCLK                                                          */
  /*    => TIM2CLK = SystemCoreClock (48 MHz)                                 */  
  tim_clk = SystemCoreClock/1;

  /* Set the TIM2 prescaler to get counter clock frequency at 4 kHz */
  /* Set the capture/compare register to get a pulse delay of 2s (2000000 us)*/
  /* Set the autoreload register to get a pulse length of 3s (3000000 us)*/
  Prescaler = __LL_TIM_CALC_PSC(tim_clk, 4000);
  Period = __LL_TIM_CALC_PULSE(tim_clk, Prescaler, 2000000, 3000000);
  Pulse = __LL_TIM_CALC_DELAY(tim_clk, Prescaler, 2000000);

  /* USER CODE END TIM2_Init 1 */
  TIM_InitStruct.Prescaler = Prescaler;
  TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
  TIM_InitStruct.Autoreload = Period;
  TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
  LL_TIM_Init(TIM2, &TIM_InitStruct);
  LL_TIM_EnableARRPreload(TIM2);
  TIM_OC_InitStruct.OCMode = LL_TIM_OCMODE_RETRIG_OPM2;
  TIM_OC_InitStruct.OCState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.OCNState = LL_TIM_OCSTATE_DISABLE;
  TIM_OC_InitStruct.CompareValue = Pulse;
  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_SetOnePulseMode(TIM2, LL_TIM_ONEPULSEMODE_SINGLE);
  LL_TIM_SetTriggerInput(TIM2, LL_TIM_TS_TI2FP2);
  LL_TIM_SetSlaveMode(TIM2, LL_TIM_SLAVEMODE_TRIGGER);
  LL_TIM_CC_DisableChannel(TIM2, LL_TIM_CHANNEL_CH2);
  LL_TIM_IC_SetFilter(TIM2, LL_TIM_CHANNEL_CH2, LL_TIM_IC_FILTER_FDIV1);
  LL_TIM_IC_SetPolarity(TIM2, LL_TIM_CHANNEL_CH2, LL_TIM_IC_POLARITY_RISING);
  LL_TIM_DisableIT_TRIG(TIM2);
  LL_TIM_DisableDMAReq_TRIG(TIM2);
  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 = LL_GPIO_PIN_5;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_VERY_HIGH;
  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);

}

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

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

  /**/
  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 */

/******************************************************************************/
/*   USER IRQ HANDLER TREATMENT                                               */
/******************************************************************************/
/**
  * @brief  User button interrupt processing
  * @note   TIM1 counter is enabled every time the user button is presssed. 
  * @param  None
  * @retval None
  */
void UserButton_Callback(void)
{
  /* Enable counter. Note that the counter will stop automatically at the     */
  /* next update event (UEV).                                                 */
  LL_TIM_EnableCounter(TIM1);
}

/**
  * @brief  Timer capture/compare interrupt processing
  * @note   Calculates the pulse delay and pulse length of the output waveform
  *         generated by TIM1.
  * @param  None
  * @retval None
  */
void TimerCaptureCompare_Callback(void)
{
  uint32_t cnt;
  uint32_t psc; 
  uint32_t arr; 
  
  cnt = LL_TIM_GetCounter(TIM1);
  psc = LL_TIM_GetPrescaler(TIM1);
  arr = LL_TIM_GetAutoReload(TIM1);
  
  uwMeasuredDelay = (cnt * 1000000)/(SystemCoreClock/(psc + 1));
  uwMeasuredPulseLength = ((arr - cnt) * 1000000)/(SystemCoreClock/(psc + 1)); 
}


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