passCode.c

/*******************************************************************************
  * File Name          : main.c
  * Version            : two
  * Description        : This version validates the input passcode for length (upto 4 digits) and only numeric digits are allowed
  *                      program written for authentication of users via passcodes of upto four digits.
  *
  *                      case 1: passcode is correct
  *                      green LED glows and a 400hz frequency auditory feedback is given via buzzer.
  *                      serial port and 16x2 LCD prints "Access Granted"
  *
  *                      case 2: passcode is incorrect
  *                      red LED glows and a 600hz frequency auditory feedback is given via buzzer.
  *                      serial port and 16x2 LCD prints "Access Denied"
  *
  *                      case 3: passcodes are incorrect three times
  *                      yellow LED glows and a 800hz frequency auditory feedback is given via buzzer.
  *                      serial port and 16x2 LCD prints "Access Blocked"
  *
  * Author:              Deep Shah
  * Date:                24th June 2021
  *******************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
/* USER CODE END Includes */

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

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
#define attemptsAllowed 3             //maximum number of wrong passcodes user can enter
/* USER CODE END PD */

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

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
TIM_HandleTypeDef htim1;

UART_HandleTypeDef huart2;

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_Init(void);
static void MX_TIM1_Init(void);
/* USER CODE BEGIN PFP */
void HD44780_Init(void);
void HD44780_PutChar(unsigned char c);
void HD44780_GotoXY(unsigned char x, unsigned char y);
void HD44780_PutStr(char *str);
void HD44780_ClrScr(void);
/* USER CODE END PFP */

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

// FUNCTION      : passCodeAuthenticator
// DESCRIPTION   : function to authenticate passcodes which gives status of either access granted, denied or blocked
// PARAMETERS    : none
// RETURNS       : void
void passCodeAuthenticator(void);


// FUNCTION      : validatePassCode
// DESCRIPTION   : function to validate whether passcode is of upto 4 digits and it is numeric
// PARAMETERS    : none
// RETURNS       : int
int validatePassCode(void);


// FUNCTION      : changeSpeakerFrequency
// DESCRIPTION   :
//   Control the frequency on TIM1 PWM output on PA7
// PARAMETERS    :
//   *htim - pointer to hal timer structure for this timer
//   newFrequency - actual frequency desired
//
// RETURNS       :
//   Nothing
static void changeSpeakerFrequency(TIM_HandleTypeDef *htim,
		uint32_t newFrequency) {

	//HAL_TIMEx_PWMN_Stop(htim, TIM_CHANNEL_1);

	// calculate the new period based off of frequency input
	uint32_t newPeriod = 1000000000 / (newFrequency * 250);

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

	htim->Instance = TIM1;
	htim->Init.Prescaler = 0;
	htim->Init.CounterMode = TIM_COUNTERMODE_UP;
	htim->Init.Period = newPeriod;
	htim->Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
	htim->Init.RepetitionCounter = 0;
	htim->Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
	if (HAL_TIM_Base_Init(htim) != HAL_OK) {
		Error_Handler();
	}
	sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
	if (HAL_TIM_ConfigClockSource(htim, &sClockSourceConfig) != HAL_OK) {
		Error_Handler();
	}
	if (HAL_TIM_PWM_Init(htim) != HAL_OK) {
		Error_Handler();
	}
	sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
	sMasterConfig.MasterOutputTrigger2 = TIM_TRGO2_RESET;
	sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
	if (HAL_TIMEx_MasterConfigSynchronization(htim, &sMasterConfig)
			!= HAL_OK) {
		Error_Handler();
	}
	sConfigOC.OCMode = TIM_OCMODE_PWM1;
	sConfigOC.Pulse = htim1.Init.Period/2;
	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.BreakFilter = 0;
	sBreakDeadTimeConfig.Break2State = TIM_BREAK2_DISABLE;
	sBreakDeadTimeConfig.Break2Polarity = TIM_BREAK2POLARITY_HIGH;
	sBreakDeadTimeConfig.Break2Filter = 0;
	sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
	if (HAL_TIMEx_ConfigBreakDeadTime(htim, &sBreakDeadTimeConfig)
			!= HAL_OK) {
		Error_Handler();
	}
	HAL_TIM_MspPostInit(htim);

	// must restart the timer once changes are complete
	HAL_TIMEx_PWMN_Start(htim, TIM_CHANNEL_1);
}
/* 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_USART2_UART_Init();
  MX_TIM1_Init();
  /* USER CODE BEGIN 2 */
	HAL_TIMEx_PWMN_Start(&htim1, TIM_CHANNEL_1);
	  HD44780_Init();
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */

  passCodeAuthenticator();                    //calling this function to authenticate passcodes


	while (1) {

    /* USER CODE END WHILE */

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

void passCodeAuthenticator(){
  int validPassCode[] = { 70, 4879, 1245, 4579, 1478, 12, 5, 78, 897, 10 };
  int enteredPassCode;
  int totalPassCode = sizeof(validPassCode)/4;  //To determine how many passcodes are there. In this case it is 10.
  bool accessGranted = false;                   //this boolean expression is helpful to evaluate what auditory signal to give
   for (int j = attemptsAllowed; j >= 1; j--){
       printf("%d attempts allowed\n", j);
	   enteredPassCode = validatePassCode();    //call validatePassCode for input validation and accept only a valid user entered passcode
	   for (int i = 0; i <= totalPassCode - 1; i++){
	     if (validPassCode[i] == enteredPassCode){
			printf("%d\n", validPassCode[i]);
			printf("Access Granted\n");                            //accepted status on serial port
			HAL_GPIO_WritePin(GPIOA, GPIO_PIN_12, GPIO_PIN_SET);   //only green LED glows
			HAL_GPIO_WritePin(GPIOA, GPIO_PIN_11, GPIO_PIN_RESET);
			HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET);
		    accessGranted = true;
			HD44780_GotoXY(0,0);
	        HD44780_PutStr("Access Granted");                      //accepted status on lcd
			changeSpeakerFrequency(&htim1, 400);                   //400Hz auditory feedback
		    break;
		  }
	   }
	     if (accessGranted == false) {
		    printf("Access Denied\n");                               //denied status on serial port
		    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_12, GPIO_PIN_RESET);
		    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_11, GPIO_PIN_SET);     //only red LED glows
		    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_RESET);
		    HD44780_GotoXY(0,0);
		    HD44780_PutStr("Access Denied");                         //denied status on lcd
		    changeSpeakerFrequency(&htim1, 600);                     //600Hz auditory feedback
	        }
	       else{
	    	  break;
	       }
  }
	    if (accessGranted == false){
	        printf("Access Blocked\n");                           //blocked status on serial port if three wrong passcodes are entered
	        HAL_GPIO_WritePin(GPIOA, GPIO_PIN_12, GPIO_PIN_RESET);
	        HAL_GPIO_WritePin(GPIOA, GPIO_PIN_11, GPIO_PIN_RESET);
	        HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, GPIO_PIN_SET);   //only yellow LED glows
	        HD44780_GotoXY(0,0);
	        HD44780_PutStr("Access Blocked");                     //blocked status on lcd
	        changeSpeakerFrequency(&htim1, 800);                  //800Hz auditory feedback
         }
}

int validatePassCode() {
    bool passCodeLengthAcceptable = false;
    bool passCodeNumericAcceptable = true;
    char enteredString[15];                  //maximum digits a user can enter. In this case it is 15.
    int returnValue;
    gets(enteredString);
    for (int k = 1; k <= 4; k++) {           //if a null character is detected between index 1 and 4 then length wise passcode is valid
        if (enteredString[k] == '\0') {
            passCodeLengthAcceptable = true;
        }
    }


    int c = strlen(enteredString);           //calculate input string length


    if (passCodeLengthAcceptable == true) {  //if passcode length is acceptable then only proceed to check if it only contains integers
        for (int x = 0; x <= c - 1; x++) {   //this loop checks integers from index 0 to length of string - 1 (one is subtracted because we don't want to check null character at the end of the string, as null character will always be present in a string)
            if (!isdigit(enteredString[x])) {
                passCodeNumericAcceptable = false;
            }
        }
    }

   // if-else to determine what integer value to return
    if (passCodeLengthAcceptable && passCodeNumericAcceptable) {
        returnValue = atoi(enteredString);  //if length and no alphabets in the input then only convert the given string into digits
    }
    else {
        returnValue = 12345;                //as we can only return an integer even if the input string is not valid. We return an invalid passcode (which is of more than 4 digits)
    }
    return returnValue;
}
/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

  /** Configure LSE Drive Capability
  */
  HAL_PWR_EnableBkUpAccess();
  __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);
  /** Initializes the RCC Oscillators according to the specified parameters
  * in the RCC_OscInitTypeDef structure.
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE|RCC_OSCILLATORTYPE_MSI;
  RCC_OscInitStruct.LSEState = RCC_LSE_ON;
  RCC_OscInitStruct.MSIState = RCC_MSI_ON;
  RCC_OscInitStruct.MSICalibrationValue = 0;
  RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_6;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI;
  RCC_OscInitStruct.PLL.PLLM = 1;
  RCC_OscInitStruct.PLL.PLLN = 16;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7;
  RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
  RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
  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_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV16;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
  {
    Error_Handler();
  }
  PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART2;
  PeriphClkInit.Usart2ClockSelection = RCC_USART2CLKSOURCE_PCLK1;
  if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure the main internal regulator output voltage
  */
  if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK)
  {
    Error_Handler();
  }
  /** Enable MSI Auto calibration
  */
  HAL_RCCEx_EnableMSIPLLMode();
}

/**
  * @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 = 0;
  htim1.Init.CounterMode = TIM_COUNTERMODE_UP;
  htim1.Init.Period = 65535;
  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.MasterOutputTrigger2 = TIM_TRGO2_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.BreakFilter = 0;
  sBreakDeadTimeConfig.Break2State = TIM_BREAK2_DISABLE;
  sBreakDeadTimeConfig.Break2Polarity = TIM_BREAK2POLARITY_HIGH;
  sBreakDeadTimeConfig.Break2Filter = 0;
  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 USART2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 115200;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_NONE;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
  huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_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_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8|GPIO_PIN_11|GPIO_PIN_12, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LD3_GPIO_Port, LD3_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pins : PA8 PA11 PA12 */
  GPIO_InitStruct.Pin = GPIO_PIN_8|GPIO_PIN_11|GPIO_PIN_12;
  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);

  /*Configure GPIO pin : LD3_Pin */
  GPIO_InitStruct.Pin = LD3_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LD3_GPIO_Port, &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 */

  /* 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,
     tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/