/**
  ******************************************************************************
  * @file    TIM/TIM_PWMOutput/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use STM32F3xx TIM HAL API to generate
  *          4 signals in PWM.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/** @addtogroup STM32F3xx_HAL_Examples
  * @{
  */

/** @addtogroup TIM_PWMOutput
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
#define  PERIOD_VALUE       (uint32_t)(444 - 1)  /* Period Value  */
#define  PULSE1_VALUE       (uint32_t)(PERIOD_VALUE/2)        /* Capture Compare 1 Value  */
#define  PULSE2_VALUE       (uint32_t)(PERIOD_VALUE*37.5/100) /* Capture Compare 2 Value  */
#define  PULSE3_VALUE       (uint32_t)(PERIOD_VALUE/4)        /* Capture Compare 3 Value  */
#define  PULSE4_VALUE       (uint32_t)(PERIOD_VALUE*12.5/100) /* Capture Compare 4 Value  */

/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Timer handler declaration */
TIM_HandleTypeDef    TimHandle;

/* Timer Output Compare Configuration Structure declaration */
TIM_OC_InitTypeDef sConfig;

/* Counter Prescaler value */
uint32_t uhPrescalerValue = 0;

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void Error_Handler(void);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
int main(void)
{
  /* STM32F3xx HAL library initialization:
       - Configure the Flash prefetch
       - Configure the Systick to generate an interrupt each 1 msec
       - Set NVIC Group Priority to 4
       - Low Level Initialization
     */
  HAL_Init();

  /* Configure the system clock to 64 MHz */
  SystemClock_Config();

  /* Configure LED3 */
  BSP_LED_Init(LED3);

  /* Compute the prescaler value to have TIM2 counter clock equal to 16000000 Hz */
  uhPrescalerValue = (uint32_t)(SystemCoreClock / 16000000) - 1;

  /*##-1- Configure the TIM peripheral #######################################*/
  /* -----------------------------------------------------------------------
  TIM2 Configuration: generate 4 PWM signals with 4 different duty cycles.

    In this example TIM2 input clock (TIM2CLK) is set to 2 * APB1 clock (PCLK1), 
    since APB1 prescaler is different from 1.   
      TIM2CLK = 2 * PCLK1  
      PCLK1 = HCLK / 2 
      => TIM2CLK = HCLK = SystemCoreClock

    To get TIM2 counter clock at 16 MHz, the prescaler is computed as follows:
       Prescaler = (TIM2CLK / TIM2 counter clock) - 1
       Prescaler = (SystemCoreClock /16 MHz) - 1
                                              
    To get TIM2 output clock at 36 KHz, the period (ARR)) is computed as follows:
       ARR = (TIM2 counter clock / TIM2 output clock) - 1
           = 443

    TIM2 Channel1 duty cycle = (TIM2_CCR1/ TIM2_ARR + 1)* 100 = 50%
    TIM2 Channel2 duty cycle = (TIM2_CCR2/ TIM2_ARR + 1)* 100 = 37.5%
    TIM2 Channel3 duty cycle = (TIM2_CCR3/ TIM2_ARR + 1)* 100 = 25%
    TIM2 Channel4 duty cycle = (TIM2_CCR4/ TIM2_ARR + 1)* 100 = 12.5%

    Note:
     SystemCoreClock variable holds HCLK frequency and is defined in system_stm32f3xx.c file.
     Each time the core clock (HCLK) changes, user had to update SystemCoreClock
     variable value. Otherwise, any configuration based on this variable will be incorrect.
     This variable is updated in three ways:
      1) by calling CMSIS function SystemCoreClockUpdate()
      2) by calling HAL API function HAL_RCC_GetSysClockFreq()
      3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency
  ----------------------------------------------------------------------- */

  /* Initialize TIMx peripheral as follows:
       + Prescaler = (SystemCoreClock / 16000000) - 1
       + Period = (444 - 1)
       + ClockDivision = 0
       + Counter direction = Up
  */
  TimHandle.Instance = TIMx;

  TimHandle.Init.Prescaler         = uhPrescalerValue;
  TimHandle.Init.Period            = PERIOD_VALUE;
  TimHandle.Init.ClockDivision     = 0;
  TimHandle.Init.CounterMode       = TIM_COUNTERMODE_UP;
  TimHandle.Init.RepetitionCounter = 0;
  TimHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_PWM_Init(&TimHandle) != HAL_OK)
  {
    /* Initialization Error */
    Error_Handler();
  }

  /*##-2- Configure the PWM channels #########################################*/
  /* Common configuration for all channels */
  sConfig.OCMode       = TIM_OCMODE_PWM1;
  sConfig.OCPolarity   = TIM_OCPOLARITY_HIGH;
  sConfig.OCFastMode   = TIM_OCFAST_DISABLE;
  sConfig.OCNPolarity  = TIM_OCNPOLARITY_HIGH;
  sConfig.OCNIdleState = TIM_OCNIDLESTATE_RESET;

  sConfig.OCIdleState  = TIM_OCIDLESTATE_RESET;

  /* Set the pulse value for channel 1 */
  sConfig.Pulse = PULSE1_VALUE;
  if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, TIM_CHANNEL_1) != HAL_OK)
  {
    /* Configuration Error */
    Error_Handler();
  }

  /* Set the pulse value for channel 2 */
  sConfig.Pulse = PULSE2_VALUE;
  if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, TIM_CHANNEL_2) != HAL_OK)
  {
    /* Configuration Error */
    Error_Handler();
  }

  /* Set the pulse value for channel 3 */
  sConfig.Pulse = PULSE3_VALUE;
  if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, TIM_CHANNEL_3) != HAL_OK)
  {
    /* Configuration Error */
    Error_Handler();
  }

  /* Set the pulse value for channel 4 */
  sConfig.Pulse = PULSE4_VALUE;
  if (HAL_TIM_PWM_ConfigChannel(&TimHandle, &sConfig, TIM_CHANNEL_4) != HAL_OK)
  {
    /* Configuration Error */
    Error_Handler();
  }

  /*##-3- Start PWM signals generation #######################################*/
  /* Start channel 1 */
  if (HAL_TIM_PWM_Start(&TimHandle, TIM_CHANNEL_1) != HAL_OK)
  {
    /* PWM Generation Error */
    Error_Handler();
  }
  /* Start channel 2 */
  if (HAL_TIM_PWM_Start(&TimHandle, TIM_CHANNEL_2) != HAL_OK)
  {
    /* PWM Generation Error */
    Error_Handler();
  }
  /* Start channel 3 */
  if (HAL_TIM_PWM_Start(&TimHandle, TIM_CHANNEL_3) != HAL_OK)
  {
    /* PWM generation Error */
    Error_Handler();
  }
  /* Start channel 4 */
  if (HAL_TIM_PWM_Start(&TimHandle, TIM_CHANNEL_4) != HAL_OK)
  {
    /* PWM generation Error */
    Error_Handler();
  }

  while (1)
  {
  }

}

/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
static void Error_Handler(void)
{
  /* Turn LED3 on */
  BSP_LED_On(LED3);
  while (1)
  {
  }
}

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow : 
  *            System Clock source            = PLL (HSI)
  *            SYSCLK(Hz)                     = 64000000
  *            HCLK(Hz)                       = 64000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 2
  *            APB2 Prescaler                 = 1
  *            PLLMUL                         = RCC_PLL_MUL16 (16)
  *            Flash Latency(WS)              = 2
  * @param  None
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;
  
  /* HSI Oscillator already ON after system reset, activate PLL with HSI as source */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_NONE;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL16;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct)!= HAL_OK)
  {
    /* Initialization Error */
    while(1); 
  }

  /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
     clocks dividers */
  RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;  
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2)!= HAL_OK)
  {
    /* Initialization Error */
    while(1); 
  }
}
#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 can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */
  while (1)
  {
  }
}

#endif

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
