STM32F767 Window Watchdog Initialize Problem (System Always Get Reset)

[emirhan37]

Hi for everyone,

I try to implement window watchdog to my system. I got reset every single time during enabling watchdog in HAL_WWDG_Init() function and exactly WRITE_REG(hwwdg->Instance->CR, (WWDG_CR_WDGA | hwwdg->Init.Counter)); here.

These are my watchdog configuration

  hwwdg.Instance = WWDG;
  hwwdg.Init.Prescaler = WWDG_PRESCALER_8;
  hwwdg.Init.Window = 64;
  hwwdg.Init.Counter = 127;
  hwwdg.Init.EWIMode = WWDG_EWI_DISABLE;

I want to start watchdog and feed periodically but now, I just got reset and even dont even initialize successfully. It is default init function of library as you know. What should I do to successfully initialize Watchdog, feed it periodically, and ensure it runs properly?

I will be grateful for your help.

[TDK]

Here is an example WWDG usage. I'd recommend getting that up and running.

STM32CubeF7/Projects/STM32F722ZE-Nucleo/Examples/WWDG/WWDG_Example/Src/main.c at 18642033f376dead4f28f09f21b5ae75abb4020e · STMicroelectronics/STM32CubeF7

Unlike the IWDG, the WWDG requires you to refresh it within a particular window. If you refresh outside of that window, it will reset. In your program, how do you ensure you're refreshing within that window?

The code presented looks fine.

[emirhan37]

Thanks for reply.

I tried the example already but I am facing a problem in init function

HAL_StatusTypeDef HAL_WWDG_Init(WWDG_HandleTypeDef *hwwdg)
{
  /* Check the WWDG handle allocation */
  if (hwwdg == NULL)
  {
    return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_WWDG_ALL_INSTANCE(hwwdg->Instance));
  assert_param(IS_WWDG_PRESCALER(hwwdg->Init.Prescaler));
  assert_param(IS_WWDG_WINDOW(hwwdg->Init.Window));
  assert_param(IS_WWDG_COUNTER(hwwdg->Init.Counter));
  assert_param(IS_WWDG_EWI_MODE(hwwdg->Init.EWIMode));

#if (USE_HAL_WWDG_REGISTER_CALLBACKS == 1)
  /* Reset Callback pointers */
  if (hwwdg->EwiCallback == NULL)
  {
    hwwdg->EwiCallback = HAL_WWDG_EarlyWakeupCallback;
  }

  if (hwwdg->MspInitCallback == NULL)
  {
    hwwdg->MspInitCallback = HAL_WWDG_MspInit;
  }

  /* Init the low level hardware */
  hwwdg->MspInitCallback(hwwdg);
#else
  /* Init the low level hardware */
  HAL_WWDG_MspInit(hwwdg);
#endif /* USE_HAL_WWDG_REGISTER_CALLBACKS */

  /* Set WWDG Counter */
  WRITE_REG(hwwdg->Instance->CR, (WWDG_CR_WDGA | hwwdg->Init.Counter));

  /* Set WWDG Prescaler and Window */
  WRITE_REG(hwwdg->Instance->CFR, (hwwdg->Init.EWIMode | hwwdg->Init.Prescaler | hwwdg->Init.Window));

  /* Return function status */
  return HAL_OK;
}

WRITE_REG(hwwdg->Instance->CR, (WWDG_CR_WDGA | hwwdg->Init.Counter)); line reset the system.

I created a timer to periodically refresh the watchdog every 20 seconds, but the main problem is I cannot skip wwdg_init successfully. I get reset just after enabling watchdog. My APB1 peripheral clock is 54 MHz. (maximum speed)

  hwwdg.Instance = WWDG;
  hwwdg.Init.Prescaler = WWDG_PRESCALER_8;
  hwwdg.Init.Window = 64;
  hwwdg.Init.Counter = 127;
  hwwdg.Init.EWIMode = WWDG_EWI_DISABLE;

and there is my watchdog configuration. What can I do now in this situation? Waiting for your answers.