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jdo
jdo
Associate III
August 11, 2022
Solved

measuring timing in tim3 interrup with stm32f030k6t6 is wrong in analyzer logic

  • August 11, 2022
  • 3 replies
  • 4030 views

hi! i am using timer interrup tim3 in stm32f030k6t6, i want configure diferent timer update for 5ms, i am using the ecuation: tout=(prescaler*preload)/(clock_frecuency). other ecuation for preload is : preload=(tout*clock_frecuency)/(prescaler). now for 5ms(0,005s) the preload is: preload=(0.005*48*1000000)/100 , preload=2400, prescaler=100, clock_frecuency= 48Mhz.0693W00000QNVeRQAX.jpg 

the timer is configurate with value, the code is:

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @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.
 *
 ******************************************************************************
 */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.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 ---------------------------------------------------------*/
 
/* USER CODE BEGIN PV */
 
/* USER CODE END PV */
 
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM16_Init(void);
static void MX_TIM3_Init(void);
/* 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();
 MX_TIM16_Init();
 MX_TIM3_Init();
 /* USER CODE BEGIN 2 */
 
 /*---------------------------------------------------------*/
 /*---------------------------------------------------------*/
 /*------------ habilita interrupcion del timer -----------*/
 LL_TIM_EnableIT_UPDATE(TIM3);
 // LL_TIM_EnableIT_UPDATE(TIM14);
 // LL_TIM_EnableIT_UPDATE(TIM16);
 /*---------------------------------------------------------*/
 /*---------- inicializa el contador ------------------------*/
 LL_TIM_EnableCounter(TIM3);
 // LL_TIM_EnableCounter(TIM14);
 // LL_TIM_EnableCounter(TIM16);
 // LL_TIM_EnableCounter(TIM17);
 
 /* USER CODE END 2 */
 
 /* 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};
 
 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
 RCC_OscInitStruct.HSIState = RCC_HSI_ON;
 RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
 RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL12;
 RCC_OscInitStruct.PLL.PREDIV = RCC_PREDIV_DIV1;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }
 
 /** Initializes the CPU, AHB and APB buses clocks
 */
 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
 |RCC_CLOCKTYPE_PCLK1;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 
 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
 {
 Error_Handler();
 }
}
 
/**
 * @brief TIM3 Initialization Function
 * @param None
 * @retval None
 */
static void MX_TIM3_Init(void)
{
 
 /* USER CODE BEGIN TIM3_Init 0 */
 
 /* USER CODE END TIM3_Init 0 */
 
 LL_TIM_InitTypeDef TIM_InitStruct = {0};
 
 /* Peripheral clock enable */
 LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_TIM3);
 
 /* TIM3 interrupt Init */
 NVIC_SetPriority(TIM3_IRQn, 0);
 NVIC_EnableIRQ(TIM3_IRQn);
 
 /* USER CODE BEGIN TIM3_Init 1 */
 
 /* USER CODE END TIM3_Init 1 */
 TIM_InitStruct.Prescaler = 1000;
 TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
 TIM_InitStruct.Autoreload = 2400;
 TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
 LL_TIM_Init(TIM3, &TIM_InitStruct);
 LL_TIM_EnableARRPreload(TIM3);
 LL_TIM_SetClockSource(TIM3, LL_TIM_CLOCKSOURCE_INTERNAL);
 LL_TIM_SetTriggerOutput(TIM3, LL_TIM_TRGO_RESET);
 LL_TIM_DisableMasterSlaveMode(TIM3);
 /* USER CODE BEGIN TIM3_Init 2 */
 
 /* USER CODE END TIM3_Init 2 */
 
}
 
/**
 * @brief TIM16 Initialization Function
 * @param None
 * @retval None
 */
static void MX_TIM16_Init(void)
{
 
 /* USER CODE BEGIN TIM16_Init 0 */
 
 /* USER CODE END TIM16_Init 0 */
 
 LL_TIM_InitTypeDef TIM_InitStruct = {0};
 
 /* Peripheral clock enable */
 LL_APB1_GRP2_EnableClock(LL_APB1_GRP2_PERIPH_TIM16);
 
 /* TIM16 interrupt Init */
 NVIC_SetPriority(TIM16_IRQn, 0);
 NVIC_EnableIRQ(TIM16_IRQn);
 
 /* USER CODE BEGIN TIM16_Init 1 */
 
 /* USER CODE END TIM16_Init 1 */
 TIM_InitStruct.Prescaler = 1000;
 TIM_InitStruct.CounterMode = LL_TIM_COUNTERMODE_UP;
 TIM_InitStruct.Autoreload = 274;
 TIM_InitStruct.ClockDivision = LL_TIM_CLOCKDIVISION_DIV1;
 TIM_InitStruct.RepetitionCounter = 0;
 LL_TIM_Init(TIM16, &TIM_InitStruct);
 LL_TIM_EnableARRPreload(TIM16);
 /* USER CODE BEGIN TIM16_Init 2 */
 
 /* USER CODE END TIM16_Init 2 */
 
}
 
/**
 * @brief GPIO Initialization Function
 * @param None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
 
 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOA_CLK_ENABLE();
 
 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(GPIOA, sal1_Pin|sal2_Pin, GPIO_PIN_RESET);
 
 /*Configure GPIO pins : sal1_Pin sal2_Pin */
 GPIO_InitStruct.Pin = sal1_Pin|sal2_Pin;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
 
}
 
/* USER CODE BEGIN 4 */
 
/* USER CODE END 4 */
 
/**
 * @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 */
 

the timer interrup is:

i view with analyzer logic the time, but is not true value, the time is wrong.

0693W00000QNVfoQAH.jpg 

the time is 2.9 us ever, i want 5ms the update timer interrup

This topic has been closed for replies.
Best answer by Tesla DeLorean

The interrupt handler needs to clear the source of the interrupt

Also when posting please trim off all the irrelevant commentary.

  1. void TIM3_IRQHandler(void)
  2. {
  3. if (TIM3->SR & 1) // Validate Update Source
  4. {
  5. TIM3->SR = ~1; // Clear Update
  6.  
  7. HAL_GPIO_TogglePin(GPIOA, sal1_Pin);
  8. HAL_GPIO_TogglePin(GPIOA, sal2_Pin);
  9. }
  10. }

3 replies

KnarfB
KnarfB
Super User
August 11, 2022

The counters start at 0, so you must subtract a 1.

Therefore, a prescaler of 47 will downscale the timer clock from 48 MHz to 1 MHz. In upcounting mode, the timer will increment once per µs. To get 5ms update intervalls, set TIM3_ARR to 4999. Seems like you generate an interrupt and toggle the output from the interrupt handler? This could also be done by using output compare/PWM modes with dedicated timer channels without depending on any software (IRQ). Keep also in mind, that the clock tree may generate lower clocks for APB busses/timers, check clock configuration.

hth

KnarfB

jdo
jdoAuthor
Associate III
August 12, 2022

configure the prescaler of 47 and tim3_ARR to 4999 and continue the value equal 2.9 us, i have configuration wrong?

0693W00000QNZsrQAH.jpg0693W00000QNZsmQAH.jpg0693W00000QNZshQAH.jpg

Piranha
Piranha
Principal III
August 11, 2022

Also the prescaler and autoreload values in code doesn't correspond to the ones described in the topic.

jdo
jdoAuthor
Associate III
August 12, 2022

yes, this is diferent, but with prerscaler 100 and autoreload 2400 the time is wrong. i do diferents test, i don´t know what configuration is wrong, i am doing configuration with projet manager.

Tesla DeLorean
Tesla DeLoreanAnswer
Guru
August 12, 2022

The interrupt handler needs to clear the source of the interrupt

Also when posting please trim off all the irrelevant commentary.

  1. void TIM3_IRQHandler(void)
  2. {
  3. if (TIM3->SR & 1) // Validate Update Source
  4. {
  5. TIM3->SR = ~1; // Clear Update
  6.  
  7. HAL_GPIO_TogglePin(GPIOA, sal1_Pin);
  8. HAL_GPIO_TogglePin(GPIOA, sal2_Pin);
  9. }
  10. }

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jdo
jdoAuthor
Associate III
August 12, 2022

thanks, this is the correct answell, clear the source of the interrupt.

Tesla DeLorean
Tesla DeLorean
Guru
August 12, 2022

Then please mark my answer as the best/correct one. Thanks

Apparently this makes the Search work more better..

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