Hi,
I am using a STM32C031G6U6 and I would appreciate some clarification regarding HAL timebase and SysTick timebase selection.
I want to use SysTick as a 1ms interrupt so in CubeMX I selected SysTick as timebase (see screenshot):
None of the other timers - including TIM3 - are not enabled as shown here:
These are the other settings:
I then generated the code.
But there is no sign of any SysTick related functions/handlers in the interrupt file stm32c0xx_it.c as you can see here:
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file stm32c0xx_it.c
* @brief Interrupt Service Routines.
******************************************************************************
* @attention
*
* Copyright (c) 2026 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 "stm32c0xx_it.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/******************************************************************************/
/* Cortex Processor Interruption and Exception Handlers */
/******************************************************************************/
/**
* @brief This function handles Non maskable interrupt.
*/
void NMI_Handler(void)
{
/* USER CODE BEGIN NonMaskableInt_IRQn 0 */
/* USER CODE END NonMaskableInt_IRQn 0 */
/* USER CODE BEGIN NonMaskableInt_IRQn 1 */
while (1)
{
}
/* USER CODE END NonMaskableInt_IRQn 1 */
}
/**
* @brief This function handles Hard fault interrupt.
*/
void HardFault_Handler(void)
{
/* USER CODE BEGIN HardFault_IRQn 0 */
/* USER CODE END HardFault_IRQn 0 */
while (1)
{
/* USER CODE BEGIN W1_HardFault_IRQn 0 */
/* USER CODE END W1_HardFault_IRQn 0 */
}
}
On the other hand it does seem that TIM3 is somehow used/generated in the generated code in the file stm32c0xx_hal_timebase_tim_template.c (see below).
/**
******************************************************************************
* @file stm32c0xx_hal_timebase_tim_template.c
* @author MCD Application Team
* @brief HAL time base based on the hardware TIM.
*
* This file overrides the native HAL time base functions (defined as weak)
* the TIM time base:
* + Initializes the TIM peripheral to generate a Period elapsed Event each 1ms
* + HAL_IncTick is called inside HAL_TIM_PeriodElapsedCallback ie each 1ms
*
******************************************************************************
* @attention
*
* Copyright (c) 2022 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.
*
******************************************************************************
@verbatim
==============================================================================
##### How to use this driver #####
==============================================================================
[..]
This file must be copied to the application folder and modified as follows:
(#) Rename it to 'stm32c0xx_hal_timebase_tim.c'
(#) Add this file and the TIM HAL drivers to your project and uncomment
HAL_TIM_MODULE_ENABLED define in stm32c0xx_hal_conf.h
@endverbatim
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32c0xx_hal.h"
/** @addtogroup STM32C0xx_HAL_Driver
* @{
*/
/** @addtogroup HAL_TimeBase_TIM
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
extern TIM_HandleTypeDef TimHandle;
TIM_HandleTypeDef TimHandle;
/* Private function prototypes -----------------------------------------------*/
void TIM3_IRQHandler(void);
/* Private functions ---------------------------------------------------------*/
/**
* @brief This function configures the TIM3 as a time base source.
* The time source is configured to have 1ms time base with a dedicated
* Tick interrupt priority.
* @note This function is called automatically at the beginning of program after
* reset by HAL_Init() or at any time when clock is configured, by HAL_RCC_ClockConfig().
* TickPriority Tick interrupt priority.
* @retval HAL status
*/
HAL_StatusTypeDef HAL_InitTick(uint32_t TickPriority)
{
RCC_ClkInitTypeDef clkconfig;
uint32_t uwTimclock;
uint32_t uwAPB1Prescaler;
uint32_t uwPrescalerValue;
uint32_t pFLatency;
/*Configure the TIM3 IRQ priority */
HAL_NVIC_SetPriority(TIM3_IRQn, TickPriority, 0U);
/* Enable the TIM3 global Interrupt */
HAL_NVIC_EnableIRQ(TIM3_IRQn);
/* Enable TIM3 clock */
__HAL_RCC_TIM3_CLK_ENABLE();
/* Get clock configuration */
HAL_RCC_GetClockConfig(&clkconfig, &pFLatency);
/* Get APB1 prescaler */
uwAPB1Prescaler = clkconfig.APB1CLKDivider;
/* Compute TIM3 clock */
if (uwAPB1Prescaler == RCC_APB1_DIV1)
{
uwTimclock = HAL_RCC_GetPCLK1Freq();
}
else
{
uwTimclock = 2U * HAL_RCC_GetPCLK1Freq();
}
/* Compute the prescaler value to have TIM3 counter clock equal to 1MHz */
uwPrescalerValue = (uint32_t)((uwTimclock / 1000000U) - 1U);
/* Initialize TIM3 */
TimHandle.Instance = TIM3;
/* Initialize TIMx peripheral as follow:
+ Period = [(TIM3CLK/1000) - 1]. to have a (1/1000) s time base.
+ Prescaler = (uwTimclock/1000000 - 1) to have a 1MHz counter clock.
+ ClockDivision = 0
+ Counter direction = Up
*/
TimHandle.Init.Period = (1000000U / 1000U) - 1U;
TimHandle.Init.Prescaler = uwPrescalerValue;
TimHandle.Init.ClockDivision = 0U;
TimHandle.Init.CounterMode = TIM_COUNTERMODE_UP;
TimHandle.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&TimHandle) == HAL_OK)
{
/* Start the TIM time Base generation in interrupt mode */
return HAL_TIM_Base_Start_IT(&TimHandle);
}
/* Return function status */
return HAL_ERROR;
}
/**
* @brief Suspend Tick increment.
* @note Disable the tick increment by disabling TIM3 update interrupt.
* @retval None
*/
void HAL_SuspendTick(void)
{
/* Disable TIM3 update interrupt */
__HAL_TIM_DISABLE_IT(&TimHandle, TIM_IT_UPDATE);
}
/**
* @brief Resume Tick increment.
* @note Enable the tick increment by enabling TIM3 update interrupt.
* @retval None
*/
void HAL_ResumeTick(void)
{
/* Enable TIM3 update interrupt */
__HAL_TIM_ENABLE_IT(&TimHandle, TIM_IT_UPDATE);
}
/**
* @brief Period elapsed callback in non blocking mode
* @note This function is called when TIM3 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.
* htim TIM handle
* @retval None
*/
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
HAL_IncTick();
}
/**
* @brief This function handles TIM interrupt request.
* @retval None
*/
void TIM3_IRQHandler(void)
{
HAL_TIM_IRQHandler(&TimHandle);
}
/**
* @}
*/
/**
* @}
*/
What is happening? Am I looking in the wrong file?
Where is the SysTick handler in which I can plug my custom functions that I need to run every 1ms?
Thank you
