/**
  ******************************************************************************
  * @file    IWDG/IWDG_WindowMode/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use the STM32F0xx IWDG HAL API
  *          to update at regular period the IWDG counter and how to simulate a
  *          software fault generating an MCU IWDG reset on expiry of a
  *          programmed time period.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

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

/** @addtogroup STM32F0xx_HAL_Examples
  * @{
  */

/** @addtogroup IWDG_WindowMode
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* IWDG and TIM handlers declaration */
IWDG_HandleTypeDef IwdgHandle;
RCC_ClkInitTypeDef RCC_ClockFreq;

/* In while loop, time to wait before refresh */
__IO uint32_t WaitingDelay = 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)
{
  GPIO_InitTypeDef  GPIO_InitStruct;

  /* STM32F0xx HAL library initialization:
       - Configure the Flash prefetch
       - Systick timer is configured by default as source of time base, but user 
             can eventually implement his proper time base source (a general purpose 
             timer for example or other time source), keeping in mind that Time base 
             duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and 
             handled in milliseconds basis.
       - Low Level Initialization
     */
  HAL_Init();
  
  /* Configure the system clock to 48 MHz */
  SystemClock_Config();

  /* Configure LED3 */
  BSP_LED_Init(LED3);

  /* Configure PA.12 (Arduino D2) as input with External interrupt */
  GPIO_InitStruct.Pin = GPIO_PIN_12;
  GPIO_InitStruct.Pull = GPIO_PULLUP;
  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
  
  /* Enable GPIOA clock */
  __HAL_RCC_GPIOA_CLK_ENABLE();

  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* Enable and set PA.12 (Arduino D2) EXTI Interrupt to the lowest priority */
  NVIC_SetPriority((IRQn_Type)(EXTI4_15_IRQn), 0x03);
  HAL_NVIC_EnableIRQ((IRQn_Type)(EXTI4_15_IRQn));

  /*##-1- Check if the system has resumed from IWDG reset ####################*/
  if (__HAL_RCC_GET_FLAG(RCC_FLAG_IWDGRST) != RESET)
  {
    /* IWDGRST flag set: Turn LED3 on */
    BSP_LED_On(LED3);

    /* Insert 4s delay */
    HAL_Delay(4000);

    /* Prior to clear IWDGRST flag: Turn LED3 off */
    BSP_LED_Off(LED3);
  }

  /* Clear reset flags anyway */
  __HAL_RCC_CLEAR_RESET_FLAGS();

  /*##-2- Configure & Start the IWDG peripheral ##############################*/
  /* Set counter reload value to obtain 762ms IWDG TimeOut.
     Counter Reload Value = (LsiFreq(Hz) * Timeout(ms)) / (prescaler * 1000)                         
  */
  IwdgHandle.Instance = IWDG;
  IwdgHandle.Init.Prescaler = IWDG_PRESCALER_16;
  IwdgHandle.Init.Reload = (40000 * 762) / (16 * 1000); /* 762 ms */
  IwdgHandle.Init.Window = (40000 * 400) / (16 * 1000); /* 400 ms */

  if(HAL_IWDG_Init(&IwdgHandle) != HAL_OK)
  {
    /* Initialization Error */
    Error_Handler();
  }

  /* Initial delay will be 450 ms in order to be inside the window */
  WaitingDelay = 450;

  /* Infinite loop */ 
  while (1)
  {
    /* Toggle LED3 */
    BSP_LED_Toggle(LED3);

    HAL_Delay(WaitingDelay);

    /* Refresh IWDG: reload counter */
    if(HAL_IWDG_Refresh(&IwdgHandle) != HAL_OK)
    {
      /* Refresh Error */
      Error_Handler();
    }
  }
}


/**
  * @brief  EXTI line detection callback to decreaase waiting delay. That will make
            refresh being outside window value.
  * @param  GPIO_Pin: Specifies the port pin connected to corresponding EXTI line.
  * @retval None
  */
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
  if(GPIO_Pin == GPIO_PIN_12)		  
  {
    /* waiting 200 ms to be above window value on next refresh */
    WaitingDelay = 200;
  }
}


/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
static void Error_Handler(void)
{
  /* Turn LED3 off */
  BSP_LED_Off(LED3);

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

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow : 
  *            System Clock source            = PLL (HSI)
  *            SYSCLK(Hz)                     = 48000000
  *            HCLK(Hz)                       = 48000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 1
  *            HSI Frequency(Hz)              = 8000000
  *            PREDIV                         = 1
  *            PLLMUL                         = 6
  *            Flash Latency(WS)              = 1
  * @param  None
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;
  
  /* No HSE Oscillator on Nucleo, 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.PREDIV = RCC_PREDIV_DIV1;
  RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL6;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct)!= HAL_OK)
  {
    /* Initialization Error */
    while(1); 
  }

  /* Select PLL as system clock source and configure the HCLK, PCLK1 clocks dividers */
  RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1);
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1)!= 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(char *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****/
