How do i insert a password change loop into my program

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1

I tried to add a feature where u can change the password but after i enter the keys to change password, it only allows me to press 2 keys and the screen will display back the "Type Password".

#include <Wire.h>                // deals with I2C connections
#include <LiquidCrystal_I2C.h>  //   activates the LCD I2C library
#include <Keypad.h>             // activates the   Keypad library

#define   Password_Length 9                    // Amount of digits plus one null character   (8 + 1 = 9) defines password length
char userInput[Password_Length];             //   This variable will store the user input in a string
char newuserInput[Password_Length];
char Master[Password_Length]  = "12345678";
char Change[Password_Length] = "99991234";     
char customKey;                              //   This variable holds key input of every key pressed
byte pressCount = 0; 

const byte ROWS = 4; // Constants for row and 
const byte COLS   = 4; // column size of your keypad.

char hexaKeys [ROWS][COLS]={
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

byte rowPins [ROWS]={9,8,7,6};
byte colPins [COLS]={5,4,3,2};

Keypad customKeypad = Keypad (makeKeymap(hexaKeys),rowPins,colPins,ROWS,COLS);

LiquidCrystal_I2C lcd (0x27,16,2);

void setup() {
  lcd.backlight(); 
  lcd.init();
  lcd.clear();

}

void loop() {
  do {
  lcd.setCursor(0,0);
  lcd.print("Type Password:");                                       //   One space is offset to center the text on the LCD
  customKey = customKeypad.waitForKey();

  if (customKey != NO_KEY && customKey != 'C' && customKey != 'D')    // If the   user presses the number keys, the data is entered
  {
   userInput[pressCount]   = customKey;  
   lcd.setCursor(pressCount + 2, 1);                                
   lcd.print("*");                                                       
   pressCount++;                                         //   Key press count will roll over until 8 digits are entered
  }
  else if   (customKey == 'C')    // C is to clear the entire password input from any point   and start over again as
  {                             // it calls up the clearData   function.
   lcd.clear();
   clearData(); 
  }
    else if (customKey   == 'D')    // D = enter,If less than 8 digits are entered, the input will be invalid and 
   {                             // an error message will flash, then call the clearData   function to
   lcd.clear();                  // start the entering process all   over again.
   lcd.setCursor(0,0);
   lcd.print("INVALID ENTRY");
   delay(800);
   clearData();
  }
    if (pressCount == 8)         // Once 8 digits   are entered, the function to check the password string is called up and
  {                            //   both the character and string data are sent to the function.
   lcd.clear();
   waitHere();                  
  }}
  while (!strcmp(userInput,Master)&&strcmp(userInput,Change));

 if (!strcmp(userInput,Change)){
    lcd.setCursor(0,0);
    lcd.print("Enter old password:");                                       //   One space is offset to center the text on the LCD
    customKey = customKeypad.waitForKey();

  if (customKey != NO_KEY && customKey != 'C' && customKey != 'D')    // If the   user presses the number keys, the data is entered
  {
   newuserInput[pressCount]   = customKey;  
   lcd.setCursor(pressCount + 2, 1);                                
   lcd.print(" ");                                                       
   pressCount++;                                         //   Key press count will roll over until 8 digits are entered
  }
  else if   (customKey == 'C')    // C is to clear the entire password input from any point   and start over again as
  {                             // it calls up the clearData   function.
   lcd.clear();
   clearData(); 
  }
    else if (customKey   == 'D')    // D = enter,If less than 8 digits are entered, the input will be invalid and 
   {                             // an error message will flash, then call the clearData   function to
   lcd.clear();                  // start the entering process all   over again.
   lcd.setCursor(0,0);
   lcd.print("INVALID ENTRY");
   delay(800);
   clearData();
  }
    if (pressCount == 8)         // Once 8 digits   are entered, the function to check the password string is called up and
  {                            //   both the character and string data are sent to the function.
   lcd.clear();
   changepassword();                  
  }
  }

  else if (!strcmp(newuserInput,Master)){
    lcd.setCursor(0,0);
    lcd.print("Enter new password:");                                       //   One space is offset to center the text on the LCD
    customKey = customKeypad.waitForKey();

   if (customKey != NO_KEY && customKey != 'C' && customKey != 'D')    // If the   user presses the number keys, the data is entered
   {
     userInput[pressCount]   = customKey;  
     lcd.setCursor(pressCount + 2, 1);                                
     lcd.print(" ");                                                       
     pressCount++;
   }    
                                       //   Key press count will roll over until 8 digits are entered
    else if   (customKey == 'C')    // C is to clear the entire password input from any point   and start over again as
    {                             // it calls up the clearData   function.
      lcd.clear();
      clearData(); 
    }
    else if (customKey   == 'D')    // D = enter,If less than 8 digits are entered, the input will be invalid and 
   {                             // an error message will flash, then call the clearData   function to
      lcd.clear();                  // start the entering process all   over again.
      lcd.setCursor(0,0);
      lcd.print("INVALID ENTRY");
      delay(800);
      clearData();
    }
    if (pressCount == 8)         // Once 8 digits   are entered, the function to check the password string is called up and
   {                            //   both the character and string data are sent to the function.
     lcd.clear();
     newpass();                  
   }    
  }
}

void waitHere(){
  lcd.setCursor(0,0);
  lcd.print("Type Password:"); 
  lcd.setCursor(0,1);
  lcd.print("  ********");  
                                                 
   customKey = customKeypad.waitForKey();        // Program will halt here until a key is pushed
  
  if (customKey != NO_KEY && customKey == 'D')  // The   ENTER button is pushed and the password goes through the routine.
  {
    lcd.clear();
    lcd.setCursor(0,0); 
    if (!strcmp(userInput, Master))             // The   user input string is matched up with the Master password string and matches up
     {                                           // running the routine to grant   access before returning back to the beginning.
     lcd.setCursor(0,0);
     lcd.print("ACCESS   GRANTED.");
     delay(5000);
     clearData(); 
    }
    else if (strcmp(userInput, Master))         //   The user input string is matched up with the Master password string and does not   match up
    { 
      if (!strcmp(userInput,Change))
        {
          lcd.setCursor(0,0);
          lcd.print("CHANGE PASSWORD");
          delay(2000);
        }  
      else 
      {                             // running the routine   to deny access before returning back to the beginning.
       lcd.setCursor(0,0);
       lcd.print("ACCESS DENIED.");
       delay(2000);
       clearData();
      }
    }
  }

  if (customKey != NO_KEY && customKey == 'C')  // If the CLEAR   button is pushed, the data is cleared and the program starts over.
  {
   lcd.clear();
   clearData(); 
  }
}

void changepassword() {

  lcd.setCursor(0,0);
  lcd.print("Enter old password:"); 
  lcd.setCursor(0,1);
  lcd.print("  ********");  
                                                 
   customKey = customKeypad.waitForKey();        // Program will halt here until a key is pushed
  
  if (customKey != NO_KEY && customKey == 'D')  // The   ENTER button is pushed and the password goes through the routine.
  {
    lcd.clear();
    lcd.setCursor(0,0); 
    if (!strcmp(newuserInput, Master))             // The   user input string is matched up with the Master password string and matches up
     {                                           // running the routine to grant   access before returning back to the beginning.
     lcd.setCursor(0,0);
     lcd.print("Password Reset.");
     delay(2000);
    }
}
}

void newpass(){
  lcd.setCursor(0,0);
  lcd.print("Enter new password:"); 
  lcd.setCursor(0,1);
  lcd.print("  ********");  
                                                 
  customKey = customKeypad.waitForKey();        // Program will halt here until a key is pushed
  
  if (customKey != NO_KEY && customKey == 'D')  // The   ENTER button is pushed and the password goes through the routine.
  {
    userInput[pressCount] = Master[pressCount];
  }  
}

void clearData() {  
  while (pressCount != 0) 
   {
  userInput[pressCount--] = 0;    // Clears out the user input data, both   digit and string data are reset to zero.
  }
  setup();                        //   Returns program back to the beginning
}
3

The first problem I saw in your code was that the "pressCount" counter has a value of 8 when you start counting for the new password.

4

You have the same block of code repeated about 4 or 5 times in your code (key input). That can all be factored out into a single function.

Also, waitForKey() can never return NO_KEY so why test for it in all your if() statements? The function will block until a key is pressed.

I would suggest rewriting your entire sketch using a state machine approach and get rid of all those loops and let loop() do what is was born to do.

Why on earth would you call setup() again? Your lcd is already initialized.

5

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