/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    Examples_LL/TIM/TIM_PWMOutput_Init/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to use a timer peripheral to generate a 
  *          PWM output signal and update PWM duty cycle.
  *          Peripheral initialization done using LL initialization function.
  ******************************************************************************
  * @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 output compare modes */
#define TIM_DUTY_CYCLES_NB 11

/* USER CODE END PD */

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

/* USER CODE END PM */

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

/* USER CODE BEGIN PV */

/* Duty cycles: D = T/P * 100%                                                */
/* where T is the pulse duration and P  the period of the PWM signal          */
static uint32_t aDutyCycle[TIM_DUTY_CYCLES_NB] = {
  0,    /*  0% */
  10,   /* 10% */
  20,   /* 20% */
  30,   /* 30% */
  40,   /* 40% */
  50,   /* 50% */
  60,   /* 60% */
  70,   /* 70% */
  80,   /* 80% */
  90,   /* 90% */
  100,  /* 100% */
};

/* Duty cycle index */
static uint8_t iDutyCycle = 0;

/* Measured duty cycle */
__IO uint32_t uwMeasuredDutyCycle = 0;

/* TIM2 Clock */
static uint32_t TimOutClock = 1;
uint32_t timxPrescaler = 0;
uint32_t timxPeriod = 0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);
/* USER CODE BEGIN PFP */
__STATIC_INLINE void Configure_DutyCycle(uint32_t D);
/* 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 pre-scaler value to have TIM2 counter clock equal to 10 kHz  */
  /* - Set the auto-reload value to have a counter frequency of 100 Hz        */
  /* TIM2CLK = SystemCoreClock / (APB prescaler & multiplier)               */
  TimOutClock = SystemCoreClock/1;
  timxPrescaler = __LL_TIM_CALC_PSC(SystemCoreClock, 10000);
  timxPeriod = __LL_TIM_CALC_ARR(TimOutClock, timxPrescaler, 100);
  /* USER CODE END SysInit */

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

  /**************************/
  /* TIM2 interrupts set-up */
  /**************************/
  /* Enable the capture/compare interrupt for channel 1 */
  LL_TIM_EnableIT_CC1(TIM2);

  /**********************************/
  /* Start output signal generation */
  /**********************************/
  /* Enable output channel 1 */
  LL_TIM_CC_EnableChannel(TIM2, LL_TIM_CHANNEL_CH1);

  /* Enable counter */
  LL_TIM_EnableCounter(TIM2);

  /* Force update generation */
  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 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);

  /* TIM2 interrupt Init */
  NVIC_SetPriority(TIM2_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(TIM2_IRQn);

  /* USER CODE BEGIN TIM2_Init 1 */

  /* USER CODE END TIM2_Init 1 */
  TIM_InitStruct.Prescaler = timxPrescaler;
  TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
  TIM_InitStruct.Autoreload = timxPeriod;
  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 = ((timxPeriod + 1 ) / 2);
  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_DOWN;
  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};

  /* 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 */

/**
  * @brief  Changes the duty cycle of the PWM signal.
  *         D = (T/P)*100
  *           where T is the pulse duration and P is the PWM signal period
  * @param  D Duty cycle
  * @retval None
  */
__STATIC_INLINE void Configure_DutyCycle(uint32_t D)
{
  uint32_t P;    /* Pulse duration */
  uint32_t T;    /* PWM signal period */
  
  /* PWM signal period is determined by the value of the auto-reload register */
  T = LL_TIM_GetAutoReload(TIM2) + 1;
  
  /* Pulse duration is determined by the value of the compare register.       */
  /* Its value is calculated in order to match the requested duty cycle.      */
  P = (D*T)/100;
  LL_TIM_OC_SetCompareCH1(TIM2, P);
}

/******************************************************************************/
/*   USER IRQ HANDLER TREATMENT                                               */
/******************************************************************************/
/**
  * @brief  User button interrupt processing
  * @note   When the user key button is pressed the PWM duty cycle is updated. 
  * @param  None
  * @retval None
  */
void UserButton_Callback(void)
{
  /* Set new duty cycle */
  iDutyCycle = (iDutyCycle + 1) % TIM_DUTY_CYCLES_NB;

  /* Change PWM signal duty cycle */
  Configure_DutyCycle(aDutyCycle[iDutyCycle]);
}

/**
  * @brief  Timer capture/compare interrupt processing
  * @param  None
  * @retval None
  */
void TimerCaptureCompare_Callback(void)
{
  uint32_t CNT, ARR;
  CNT = LL_TIM_GetCounter(TIM2);
  ARR = LL_TIM_GetAutoReload(TIM2);
  
  if (LL_TIM_OC_GetCompareCH1(TIM2) > ARR )
  {
    /* If capture/compare setting is greater than autoreload, there is a counter overflow and counter restarts from 0.
       Need to add full period to counter value (ARR+1)  */
    CNT = CNT + ARR + 1;
  }
  uwMeasuredDutyCycle = (CNT * 100) / ( ARR + 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) */
  /* Infinite loop */
  while (1)
  {
  }
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
