Timer interrupting on MCU reset

[Nico3]

Hello I have set the timer7 for 1 minute interrupt. It is working at every minute as expected. 

But the interrupt is also triggered as MCU is reset. I have set global counter for increment in timer7 callback. As soon MCU is reset , Timer7 callback is called and counter is incremented. Please suggest why it is happening.

static void MX_TIM7_Init(void)
{

/* USER CODE BEGIN TIM7_Init 0 */

/* USER CODE END TIM7_Init 0 */

TIM_MasterConfigTypeDef sMasterConfig = {0};

/* USER CODE BEGIN TIM7_Init 1 */

/* USER CODE END TIM7_Init 1 */
htim7.Instance = TIM7;
htim7.Init.Prescaler = 65400;
htim7.Init.CounterMode = TIM_COUNTERMODE_UP;
htim7.Init.Period = 44035;
htim7.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
if (HAL_TIM_Base_Init(&htim7) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_UPDATE;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim7, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}

}

//**********************************

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)

{

 

str_flag = str_flag + 1;

 

}

 

 

[TDK]

Before you start the timer and enable interrupts, generate an update event and clear the UE bit. Timers being triggered immediately can be due to the ARR register being preloaded.

[Nico3]

thanks..