text: /**
    ******************************************************************************
    * @file    stm32l4xx_hal_timebase_tim_template.c 
    * @author  MCD Application Team
    * @brief   HAL time base based on the hardware TIM Template.
    *    
    *          This file override the native HAL time base functions (defined as weak)
    *          the TIM time base:
    *           + Intializes the TIM peripheral to generate a Period elapsed Event each 1ms
    *           + HAL_IncTick is called inside HAL_TIM_PeriodElapsedCallback ie each 1ms
    * 
   @verbatim
    ==============================================================================
                          ##### How to use this driver #####
    ==============================================================================
      [..]
      This file must be copied to the application folder and modified as follows:
      (#) Rename it to 'stm32l4xx_hal_timebase_tim.c'
      (#) Add this file and the TIM HAL driver files to your project and make sure
         HAL_TIM_MODULE_ENABLED is defined in stm32l4xx_hal_conf.h 
  
      [..]
      (@) The application needs to ensure that the time base is always set to 1 millisecond
         to have correct HAL operation.
  
    @endverbatim
    ******************************************************************************
    * @attention
    *
    * <h2><center>&copy; Copyright (c) 2017 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 "stm32l4xx_hal.h"
  
  /** @addtogroup STM32L4xx_HAL_Driver
    * @{
    */
  
  /** @addtogroup HAL_TimeBase
    * @{
    */
  
  /* Private typedef -----------------------------------------------------------*/
  /* Private define ------------------------------------------------------------*/
  /* Private macro -------------------------------------------------------------*/
  /* Private variables ---------------------------------------------------------*/
  TIM_HandleTypeDef        TimHandle;
  /* Private function prototypes -----------------------------------------------*/
  void TIM6_DAC_IRQHandler(void);
  /* Private functions ---------------------------------------------------------*/
  
  /**
    * @brief  This function configures the TIM6 as a time base source. 
    *         The time source is configured  to have 1ms time base with a dedicated 
    *         Tick interrupt priority. 
    * @note   This function is called  automatically at the beginning of program after
    *         reset by HAL_Init() or at any time when clock is configured, by HAL_RCC_ClockConfig(). 
    * @param  TickPriority: Tick interrupt priority.
    * @retval HAL status
    */
  HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
  {
    RCC_ClkInitTypeDef    clkconfig;
    uint32_t              uwTimclock, uwAPB1Prescaler = 0U;
    uint32_t              uwPrescalerValue = 0U;
    uint32_t              pFLatency;
    
    /* Configure the TIM6 IRQ priority */
    HAL_NVIC_SetPriority(TIM6_DAC_IRQn, TickPriority, 0U);
    
    /* Enable the TIM6 global Interrupt */
    HAL_NVIC_EnableIRQ(TIM6_DAC_IRQn);
    
    /* Enable TIM6 clock */
    __HAL_RCC_TIM6_CLK_ENABLE();
    
    /* Get clock configuration */
    HAL_RCC_GetClockConfig(&clkconfig, &pFLatency);
    
    /* Get APB1 prescaler */
    uwAPB1Prescaler = clkconfig.APB1CLKDivider;
    
    /* Compute TIM6 clock */
    if (uwAPB1Prescaler == RCC_HCLK_DIV1) 
    {
      uwTimclock = HAL_RCC_GetPCLK1Freq();
    }
    else
    {
      uwTimclock = 2*HAL_RCC_GetPCLK1Freq();
    }
    
    /* Compute the prescaler value to have TIM6 counter clock equal to 1MHz */
    uwPrescalerValue = (uint32_t) ((uwTimclock / 1000000U) - 1U);
    
    /* Initialize TIM6 */
    TimHandle.Instance = TIM6;
    
    /* Initialize TIMx peripheral as follow:
    + Period = [(TIM6CLK/1000) - 1]. to have a (1/1000) s time base.
    + Prescaler = (uwTimclock/1000000 - 1) to have a 1MHz counter clock.
    + ClockDivision = 0
    + Counter direction = Up
    */
    TimHandle.Init.Period = (1000000U / 1000U) - 1U;
    TimHandle.Init.Prescaler = uwPrescalerValue;
    TimHandle.Init.ClockDivision = 0;
    TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
    TimHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
    if(HAL_TIM_Base_Init(&TimHandle) == HAL_OK)
    {
      /* Start the TIM time Base generation in interrupt mode */
      return HAL_TIM_Base_Start_IT(&TimHandle);
    }
    
    /* Return function status */
    return HAL_ERROR;
  }
  
  /**
    * @brief  Suspend Tick increment.
    * @note   Disable the tick increment by disabling TIM6 update interrupt.
    * @param  None
    * @retval None
    */
  void HAL_SuspendTick(void)
  {
    /* Disable TIM6 update interrupt */
    __HAL_TIM_DISABLE_IT(&TimHandle, TIM_IT_UPDATE);
  }
  
  /**
    * @brief  Resume Tick increment.
    * @note   Enable the tick increment by enabling TIM6 update interrupt.
    * @param  None
    * @retval None
    */
  void HAL_ResumeTick(void)
  {
    /* Enable TIM6 update interrupt */
    __HAL_TIM_ENABLE_IT(&TimHandle, TIM_IT_UPDATE);
  }
  
  /**
    * @brief  Period elapsed callback in non blocking mode
    * @note   This function is called  when TIM6 interrupt took place, inside
    * HAL_TIM_IRQHandler(). It makes a direct call to HAL_IncTick() to increment
    * a global variable "uwTick" used as application time base.
    * @param  htim : TIM handle
    * @retval None
    */
  void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
  {
    HAL_IncTick();
  }
  
  /**
    * @brief  This function handles TIM interrupt request.
    * @param  None
    * @retval None
    */
  void TIM6_DAC_IRQHandler(void)
  {
    HAL_TIM_IRQHandler(&TimHandle);
  }
  
  /**
    * @}
    */
  
  /**
    * @}
    */
  
  /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
  