Why can't I run the function without the flag?

[Hititli]

I want to read a linear tape encoder. If I use only one function, it works; when I use two functions, it doesn't work properly and the motor vibrates. When I use a flag, both functions work properly. Why?

Thanks.

/* 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"

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

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include "math.h"
#include <string.h>

#define WHITE		0xFFFF
#define BLACK		0x0000
#define RED		0xF800
#define GREEN		0x07E0
#define GREEN2		0xB723
#define BLUE		0x001F
#define BLUE2		0x051D
#define YELLOW		65377
#define ORANGE          0xFD20
#define CYAN		0x07FF
#define MAGENTA		0xA254
#define GRAY		0x7BEF
#define BROWN		0xBBCA

uint8_t string_tmp	[50] ;

/* 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 ---------------------------------------------------------*/
TIM_HandleTypeDef htim1;
TIM_HandleTypeDef htim2;

SRAM_HandleTypeDef hsram1;

/* USER CODE BEGIN PV */

#define LCD_REG      (*((volatile unsigned short *) 0x60000000))
#define LCD_RAM      (*((volatile unsigned short *) 0x60020000))

void lcd_Init(void);
void LcdClear(uint16_t Color);
void go_left (int16_t left);
void go_right(int16_t right);

 int pwm=150;
 char flag=0; 
 int32_t counter =0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_FMC_Init(void);
static void MX_TIM2_Init(void);
static void MX_TIM1_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

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

 ////////////////////////////////////////////////////////////
 void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef *htim)
 {
 	counter = __HAL_TIM_GET_COUNTER(&htim2);
 }

 ///////////////////<<<motor left///////////////////////
 void go_left (int16_t left) {
	 // if (flag==1){     //If I use flag it works correctly.
	 for (int i = 0; i < left; i++){
	 if (counter <15 ){pwm=175;} else {pwm=150;}
     if(counter == 0){
	     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_RESET); //flag=0;
	     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_RESET);
     } else {
    if( counter <= left ){
	     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_RESET); //left <<<<
	     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_SET);
    }
    if( counter < 0){
    HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_SET);        //right>>>>
    HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_RESET);
        }
      }
    }
	 //}
 }
 /////////////////>>>motor right///////////////////////////
 void go_right(int16_t right) {
	 //if (flag==0){         //If I use flag it works correctly.
	 for (int i = 0; i < right; i++) {
		 if (counter > right - 15 ){pwm=175;} else {pwm=150;}
	     if(counter == right){
		     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_RESET);
		     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_RESET); // flag=1;
	     } else {
	    if(counter < right){
		     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_SET);   //right >>>
		     HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_RESET);
	    }
	    if(counter > right){
	    HAL_GPIO_WritePin(GPIOE, GPIO_PIN_0, GPIO_PIN_RESET);      //left  <<<
	    HAL_GPIO_WritePin(GPIOE, GPIO_PIN_1, GPIO_PIN_SET);
	        }
	     }
       }
	 //}
 }


/* 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_FMC_Init();
  MX_TIM2_Init();
  MX_TIM1_Init();
  /* USER CODE BEGIN 2 */
  HAL_TIM_PWM_Start(&htim1, TIM_CHANNEL_1);
  HAL_TIM_Encoder_Start_IT(&htim2, TIM_CHANNEL_ALL);
  
   lcd_Init();HAL_Delay(500);LcdClear(0x22);
   Print(3,385,(uint8_t *)&"18:46",0xFC00,0x0022);
   
   HAL_GPIO_WritePin(GPIOB, GPIO_PIN_7, GPIO_PIN_SET);//LED
   //draw8bit_Bitmap(0,0,10,74,Bi,RED,ORANGE);//

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1) {
	  __HAL_TIM_SET_COMPARE(&htim1,TIM_CHANNEL_1,pwm);


	  go_right(2000); 
	  go_left (2000); 
	  
      //lcd_lineer();
	  //draw8bit_Bitmap(0,0,10,74,Bi,RED,ORANGE);

    /* 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_RCC_PWR_CLK_ENABLE();
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_ON;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 5;
  RCC_OscInitStruct.PLL.PLLN = 180;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 4;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }

  /** Activate the Over-Drive mode
  */
  if (HAL_PWREx_EnableOverDrive() != 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_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief TIM1 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_TIM1_Init(void)
{

  /* USER CODE BEGIN TIM1_Init 0 */

  /* USER CODE END TIM1_Init 0 */

  TIM_ClockConfigTypeDef sClockSourceConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};
  TIM_OC_InitTypeDef sConfigOC = {0};
  TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};

  /* USER CODE BEGIN TIM1_Init 1 */

  /* USER CODE END TIM1_Init 1 */
  htim1.Instance = TIM1;
  htim1.Init.Prescaler = 1680-1;
  htim1.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim1.Init.Period = 199;
  htim1.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim1.Init.RepetitionCounter = 0;
  htim1.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  if (HAL_TIM_Base_Init(&htim1) != HAL_OK)
  {
    Error_Handler();
  }
  sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
  if (HAL_TIM_ConfigClockSource(&htim1, &sClockSourceConfig) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_TIM_PWM_Init(&htim1) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim1, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sConfigOC.OCMode = TIM_OCMODE_PWM1;
  sConfigOC.Pulse = 0;
  sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
  sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
  sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
  sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
  sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
  if (HAL_TIM_PWM_ConfigChannel(&htim1, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
  {
    Error_Handler();
  }
  sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
  sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
  sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
  sBreakDeadTimeConfig.DeadTime = 0;
  sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
  sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
  sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
  if (HAL_TIMEx_ConfigBreakDeadTime(&htim1, &sBreakDeadTimeConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM1_Init 2 */

  /* USER CODE END TIM1_Init 2 */
  HAL_TIM_MspPostInit(&htim1);

}

/**
  * @brief TIM2 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_TIM2_Init(void)
{

  /* USER CODE BEGIN TIM2_Init 0 */

  /* USER CODE END TIM2_Init 0 */

  TIM_Encoder_InitTypeDef sConfig = {0};
  TIM_MasterConfigTypeDef sMasterConfig = {0};

  /* USER CODE BEGIN TIM2_Init 1 */

  /* USER CODE END TIM2_Init 1 */
  htim2.Instance = TIM2;
  htim2.Init.Prescaler = 0;
  htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim2.Init.Period = 4294967295;
  htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
  htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
  sConfig.EncoderMode = TIM_ENCODERMODE_TI12;
  sConfig.IC1Polarity = TIM_ICPOLARITY_FALLING;
  sConfig.IC1Selection = TIM_ICSELECTION_DIRECTTI;
  sConfig.IC1Prescaler = TIM_ICPSC_DIV1;
  sConfig.IC1Filter = 0;
  sConfig.IC2Polarity = TIM_ICPOLARITY_FALLING;
  sConfig.IC2Selection = TIM_ICSELECTION_DIRECTTI;
  sConfig.IC2Prescaler = TIM_ICPSC_DIV1;
  sConfig.IC2Filter = 0;
  if (HAL_TIM_Encoder_Init(&htim2, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
  sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
  if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN TIM2_Init 2 */

  /* USER CODE END TIM2_Init 2 */

}


/* FMC initialization function */
static void MX_FMC_Init(void)
{

  /* USER CODE BEGIN FMC_Init 0 */

  /* USER CODE END FMC_Init 0 */

  FMC_NORSRAM_TimingTypeDef Timing = {0};

  /* USER CODE BEGIN FMC_Init 1 */

  /* USER CODE END FMC_Init 1 */

  /** Perform the SRAM1 memory initialization sequence
  */
  hsram1.Instance = FMC_NORSRAM_DEVICE;
  hsram1.Extended = FMC_NORSRAM_EXTENDED_DEVICE;
  /* hsram1.Init */
  hsram1.Init.NSBank = FMC_NORSRAM_BANK1;
  hsram1.Init.DataAddressMux = FMC_DATA_ADDRESS_MUX_DISABLE;
  hsram1.Init.MemoryType = FMC_MEMORY_TYPE_SRAM;
  hsram1.Init.MemoryDataWidth = FMC_NORSRAM_MEM_BUS_WIDTH_16;
  hsram1.Init.BurstAccessMode = FMC_BURST_ACCESS_MODE_DISABLE;
  hsram1.Init.WaitSignalPolarity = FMC_WAIT_SIGNAL_POLARITY_LOW;
  hsram1.Init.WrapMode = FMC_WRAP_MODE_DISABLE;
  hsram1.Init.WaitSignalActive = FMC_WAIT_TIMING_BEFORE_WS;
  hsram1.Init.WriteOperation = FMC_WRITE_OPERATION_ENABLE;
  hsram1.Init.WaitSignal = FMC_WAIT_SIGNAL_DISABLE;
  hsram1.Init.ExtendedMode = FMC_EXTENDED_MODE_DISABLE;
  hsram1.Init.AsynchronousWait = FMC_ASYNCHRONOUS_WAIT_DISABLE;
  hsram1.Init.WriteBurst = FMC_WRITE_BURST_DISABLE;
  hsram1.Init.ContinuousClock = FMC_CONTINUOUS_CLOCK_SYNC_ONLY;
  hsram1.Init.PageSize = FMC_PAGE_SIZE_NONE;
  /* Timing */
  Timing.AddressSetupTime = 15;
  Timing.AddressHoldTime = 15;
  Timing.DataSetupTime = 255;
  Timing.BusTurnAroundDuration = 15;
  Timing.CLKDivision = 16;
  Timing.DataLatency = 17;
  Timing.AccessMode = FMC_ACCESS_MODE_A;
  /* ExtTiming */

  if (HAL_SRAM_Init(&hsram1, &Timing, NULL) != HAL_OK)
  {
    Error_Handler( );
  }

  /* USER CODE BEGIN FMC_Init 2 */

  /* USER CODE END FMC_Init 2 */
}

/**
  * @brief GPIO Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};
  /* USER CODE BEGIN MX_GPIO_Init_1 */
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOF_CLK_ENABLE();
  __HAL_RCC_GPIOG_CLK_ENABLE();

  /* USER CODE END MX_GPIO_Init_1 */

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOE, ROLE_Pin|MOTOR1_EKSI_Pin|MOTOR1_ARTI_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOB, GPIO_PIN_2|GPIO_PIN_10|LED_1_Pin|MOTOR2_ARTI_Pin
                          |MOTOR2_EKSI_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pins : ROLE_Pin MOTOR1_EKSI_Pin MOTOR1_ARTI_Pin */
  GPIO_InitStruct.Pin = ROLE_Pin|MOTOR1_EKSI_Pin|MOTOR1_ARTI_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);

  /*Configure GPIO pins : PB2 PB10 LED_1_Pin MOTOR2_ARTI_Pin
                           MOTOR2_EKSI_Pin */
  GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_10|LED_1_Pin|MOTOR2_ARTI_Pin
                          |MOTOR2_EKSI_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /* USER CODE BEGIN MX_GPIO_Init_2 */

  /* USER CODE END MX_GPIO_Init_2 */
}

/* 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 */

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