stm32 nucleo board freertos timebase source results in an infitite loop being triggered

Question

I am using a nucleo-wl55jc1 and I've attempted to setup the example from this tutorial: https://youtu.be/OPrcpbKNSjU?si=mj6qIDGve6GwYWs6

However, when I set the timebase source to anything other than SysTick to avoid the warning to produced by the cubeIDE software, the example does not function as expected. The example does work if I set the timebase source back to SysTick.

The specified LED (blue LED on PB15) never turns on, when I pause the program it shows that it is stuck in an infinite loop in the default handler in "startup_stm32wl55jcix.s", any idea what could be causing this?

Here is my main.c file:

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2025 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "cmsis_os.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

COM_InitTypeDef BspCOMInit;
/* Definitions for blink01 */
osThreadId_t blink01Handle;
const osThreadAttr_t blink01_attributes = {
  .name = "blink01",
  .priority = (osPriority_t) osPriorityNormal,
  .stack_size = 128 * 4
};
/* Definitions for blink02 */
osThreadId_t blink02Handle;
const osThreadAttr_t blink02_attributes = {
  .name = "blink02",
  .priority = (osPriority_t) osPriorityBelowNormal,
  .stack_size = 128 * 4
};
/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
void StartBlink01(void *argument);
void StartBlink02(void *argument);

/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{

  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Init scheduler */
  osKernelInitialize();

  /* USER CODE BEGIN RTOS_MUTEX */
  /* add mutexes, ... */
  /* USER CODE END RTOS_MUTEX */

  /* USER CODE BEGIN RTOS_SEMAPHORES */
  /* add semaphores, ... */
  /* USER CODE END RTOS_SEMAPHORES */

  /* USER CODE BEGIN RTOS_TIMERS */
  /* start timers, add new ones, ... */
  /* USER CODE END RTOS_TIMERS */

  /* USER CODE BEGIN RTOS_QUEUES */
  /* add queues, ... */
  /* USER CODE END RTOS_QUEUES */

  /* Create the thread(s) */
  /* creation of blink01 */
  blink01Handle = osThreadNew(StartBlink01, NULL, &blink01_attributes);

  /* creation of blink02 */
  blink02Handle = osThreadNew(StartBlink02, NULL, &blink02_attributes);

  /* USER CODE BEGIN RTOS_THREADS */
  /* add threads, ... */
  /* USER CODE END RTOS_THREADS */

  /* USER CODE BEGIN RTOS_EVENTS */
  /* add events, ... */
  /* USER CODE END RTOS_EVENTS */

  /* Initialize leds */
  BSP_LED_Init(LED_BLUE);
  BSP_LED_Init(LED_GREEN);
  BSP_LED_Init(LED_RED);

  /* Initialize USER push-button, will be used to trigger an interrupt each time it's pressed.*/
  BSP_PB_Init(BUTTON_SW1, BUTTON_MODE_EXTI);
  BSP_PB_Init(BUTTON_SW2, BUTTON_MODE_EXTI);
  BSP_PB_Init(BUTTON_SW3, BUTTON_MODE_EXTI);

  /* Initialize COM1 port (115200, 8 bits (7-bit data + 1 stop bit), no parity */
  BspCOMInit.BaudRate   = 115200;
  BspCOMInit.WordLength = COM_WORDLENGTH_8B;
  BspCOMInit.StopBits   = COM_STOPBITS_1;
  BspCOMInit.Parity     = COM_PARITY_NONE;
  BspCOMInit.HwFlowCtl  = COM_HWCONTROL_NONE;
  if (BSP_COM_Init(COM1, &BspCOMInit) != BSP_ERROR_NONE)
  {
    Error_Handler();
  }

  /* Start scheduler */
  osKernelStart();

  /* We should never get here as control is now taken by the scheduler */
  /* Boot CPU2 */
  HAL_PWREx_ReleaseCore(PWR_CORE_CPU2);

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {

    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
  RCC_OscInitStruct.MSIState = RCC_MSI_ON;
  RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_6;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure the SYSCLKSource, HCLK, PCLK1 and PCLK2 clocks dividers
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK3|RCC_CLOCKTYPE_HCLK2
                              |RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.AHBCLK2Divider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLK3Divider = RCC_SYSCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOC_CLK_ENABLE();

/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/* USER CODE BEGIN Header_StartBlink01 */
/**
  * @brief  Function implementing the blink01 thread.
  * @param  argument: Not used
  * @retval None
  */
/* USER CODE END Header_StartBlink01 */
void StartBlink01(void *argument)
{
  /* USER CODE BEGIN 5 */
  /* Infinite loop */
  for(;;)
  {
    HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_15);
    osDelay(500);
  }
  // In case we accidentally exit from task loop
  //osThreadTerminate(NULL);
  /* USER CODE END 5 */
}

/* USER CODE BEGIN Header_StartBlink02 */
/**
* @brief Function implementing the blink02 thread.
* @param argument: Not used
* @retval None
*/
/* USER CODE END Header_StartBlink02 */
void StartBlink02(void *argument)
{
  /* USER CODE BEGIN StartBlink02 */
  /* Infinite loop */
  for(;;)
  {
    HAL_GPIO_TogglePin(GPIOB, GPIO_PIN_15);
    osDelay(600);
  }
  // In case we accidentally exit from task loop
  //osThreadTerminate(NULL);
  /* USER CODE END StartBlink02 */
}

/**
  * @brief  Period elapsed callback in non blocking mode
  * @note   This function is called  when TIM1 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)
{
  /* USER CODE BEGIN Callback 0 */

  /* USER CODE END Callback 0 */
  if (htim->Instance == TIM1) {
    HAL_IncTick();
  }
  /* USER CODE BEGIN Callback 1 */

  /* USER CODE END Callback 1 */
}

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  __disable_irq();
  while (1)
  {
  }
  /* USER CODE END Error_Handler_Debug */
}

#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 CODE BEGIN 6 */
  /* 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) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

Edit:

Handler code generated by cubeIDE:

void TIM1_UP_IRQHandler(void)
{
  /* USER CODE BEGIN TIM1_UP_IRQn 0 */

  /* USER CODE END TIM1_UP_IRQn 0 */
  HAL_TIM_IRQHandler(&htim1);
  /* USER CODE BEGIN TIM1_UP_IRQn 1 */

  /* USER CODE END TIM1_UP_IRQn 1 */
}

Answer 1

The error might be in NVIC configuration for that timer. Make sure to enable the global interrupt for that timer and also set the preemption and sub priority to 0 (as it's the default priority for the sysTick timer).

Also it's better to use TIM6 or TIM7 for that purpose (if your MCU has these timers) because they are basic timers and you just need their basic features!

Answer 2

when I pause the program it shows that it is stuck in an infinite loop in the default handler in "startup_stm32wl55jcix.s", any idea what could be causing this?

Any time your app gets stuck in the default_handler, it means that it received an interrupt it wasn't prepared for. When you pause the program in that state, you can find out which interrupt(s) caused it to get there by looking in the register view in STMCubeIDE. Here's some better info on how to do that: How can I determine interrupt source on an stm32?

My best guess is that when you change the timebase to a different timer, either SysTick or that other timer is generating an interrupt, and the stm32*_it.c file doesn't have an interrupt handler defined for it.