STM32F0xx_StdPeriph_Examples/IWDG/IWDG_WindowMode/main.c

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/**
  ******************************************************************************
  * @file    IWDG/IWDG_WindowMode/main.c  
  * @author  MCD Application Team
  * @version V1.4.0
  * @date    24-July-2014
  * @brief   Main program body
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software 
  * distributed under the License is distributed on an "AS IS" BASIS, 
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

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

/** @addtogroup STM32F0xx_StdPeriph_Examples
  * @{
  */

/** @addtogroup IWDG_WindowMode
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
__IO uint32_t TimingDelay = 0;

/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program.
  * @param  None
  * @retval None
  */
int main(void)
{
  /*!< At this stage the microcontroller clock setting is already configured, 
       this is done through SystemInit() function which is called from startup
       file (startup_stm32f0xx.s) before to branch to application main.
       To reconfigure the default setting of SystemInit() function, refer to
       system_stm32f0xx.c file
     */ 
  /* Initialize LEDs and Tamper Button mounted on EVAL board */       
  STM_EVAL_LEDInit(LED1);
  STM_EVAL_LEDInit(LED2);
  STM_EVAL_LEDInit(LED3);
  STM_EVAL_PBInit(BUTTON_TAMPER, BUTTON_MODE_EXTI);

  /* Check if the system has resumed from IWDG reset */
  if (RCC_GetFlagStatus(RCC_FLAG_IWDGRST) != RESET)
  { 
    /* IWDGRST flag set */
    /* Turn on LED1 */
    STM_EVAL_LEDOn(LED1);

    /* Clear reset flags */
    RCC_ClearFlag();
  }
  else
  {
    /* IWDGRST flag is not set */
    /* Turn off LED1 */
    STM_EVAL_LEDOff(LED1);
   }
  
  /* Setup SysTick Timer for 1 msec interrupts  */
  if (SysTick_Config(SystemCoreClock / 1000))
  { 
    /* Capture error */ 
    while (1)
    {}
  }
  
  /********************* IWDG configuration ***********************************/
  /* Enable IWDG, set reload and window values to 2000 and 1000, respectively. 
     In this case the refresh window is:
     (2000-1000) / (LSI/16) = ~400 ms < refresh window < 2000 / (LSI/16) = ~800 ms

        Note: the refresh window may varies due to LSI frequency dispersion 
        ----
     */

  /* Enable IWDG (the LSI oscillator will be enabled by hardware) */
  IWDG_Enable();

  /* Enable write access to IWDG_PR and IWDG_RLR registers */
  IWDG_WriteAccessCmd(IWDG_WriteAccess_Enable);

  /* Set IWDG Prescaler value to 16 */
  IWDG_SetPrescaler(IWDG_Prescaler_16);

  /* Set IWDG Reload value to 2000 */
  IWDG_SetReload(2000);
  
  /* Wait until RVU flag is reset to be sure that the reload value
     update operation is completed */
  while(IWDG_GetFlagStatus(IWDG_FLAG_RVU) != RESET);
  
  /* Set the IWDG window value to 1000 */
  IWDG_SetWindowValue(1000);
   
  while (1)
  {
    /* Toggle LED2 */
    STM_EVAL_LEDToggle(LED2);

    /* Insert 750 ms delay */
    Delay(750);
    
    /* Reload IWDG counter */
    IWDG_ReloadCounter();
  }
}

/**
  * @brief  Inserts a delay time.
  * @param  nTime: specifies the delay time length, in 1 ms.
  * @retval None
  */
void Delay(__IO uint32_t nTime)
{
  TimingDelay = nTime;

  while(TimingDelay != 0);
}

/**
  * @brief  Decrements the TimingDelay variable.
  * @param  None
  * @retval None
  */
void TimingDelay_Decrement(void)
{
  if (TimingDelay != 0x00)
  { 
    TimingDelay--;
  }
}

#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****/