Simple arduino-based codelock

codelock.ino

//Created by Palucki @ April 2014
#include <Servo.h>

#define ClosedPos 30
#define OpenedPos 120

Servo MyServo;

const int ServoPin = 11;
const int RedLedPin = 10 ;
const int GreenLedPin = 9 ;

const int numRows = 4;       // number of rows in the keypad
const int numCols = 3;       // number of columns
const int debounceTime = 50; // number of milliseconds for switch to be stable



// keymap defines the character returned when the corresponding key is pressed
const char keymap[numRows][numCols] = {
  { '1', '2', '3'  } ,
  { '4', '5', '6'  } ,
  { '7', '8', '9'  } ,
  { '*', '0', '#'  }
};

const int rowPins[numRows] = { 8,7, 6, 5 }; // Rows 0 through 3
const int colPins[numCols] = { 4, 3, 2 };    // Columns 0 through 2

const int pass[4] = {1,2,3,4};
int userpass[4] = {-1, -1, -1 ,-1};
int state; // current state information
void setup()
{
 MyServo.attach(ServoPin); 
 pinMode(GreenLedPin, OUTPUT);
 pinMode(RedLedPin, OUTPUT);
 Serial.begin(9600);
  for (int row = 0; row < numRows; row++)
  {
    pinMode(rowPins[row],INPUT);       // Set row pins as input
    digitalWrite(rowPins[row],HIGH);   // turn on Pull-ups
  }
  for (int column = 0; column < numCols; column++)
  {
    pinMode(colPins[column],OUTPUT);     // Set column pins as outputs 
                                         // for writing
    digitalWrite(colPins[column],HIGH);  // Make all columns inactive
  }
state = 0;
closeLock();  
}

void loop()
{
  char  key = getKey();
 
 /*States:
 0 - Idle
 1 - Insert Code
 2 - Checking code & Action
 3 - Closing 
 */
 if(key != -1) //  if the character is not -1 then 
               // it's a valid key press
 {
   Serial.println("Got you ");
   Serial.println(key);
   if(key == '*')
   {
     key = getKey();
     state = 1;
   }
 switch(state)
 {
   case 0:
    Serial.println("I'm idle now");
    
     if (key== '#')
       closeLock();
     break;
   
   case 1:
     getCode(key);
     break;
   case 2:
    if(key == '#')
     verifyCode(); // check if the code matches the pattern
                   // if user press * we close the lock (state = 3)
     else
       updateUserPass(key);
     break; 
   case 3:
     closeLock();
     break;
     
   default:
   ;
 }
 }
}

// returns with the key pressed, or -1 if no key is pressed
char getKey()
{
  char key = -1;                                  // -1 indicates no key pressed

  for(int column = 0; column < numCols; column++)
  {
    digitalWrite(colPins[column],LOW);         // Activate the current column.
    for(int row = 0; row < numRows; row++)     // Scan all rows for 
                                               // a key press.
    {
      if(digitalRead(rowPins[row]) == LOW)     // Is a key pressed?
      {
        delay(debounceTime);                   // debounce
        while(digitalRead(rowPins[row]) == LOW)
            ;                                  // wait for key to be released
        key = keymap[row][column];             // Remember which key 
                                               // was pressed.
      }
    }
    digitalWrite(colPins[column],HIGH);     // De-activate the current column.
  }
  return key;  // returns the key pressed or -1 if none
}

void getCode(char uKey)
{
  //Serial.println("State 1 - Getting Code");
  int i=0;
  while(userpass[i] !=  -1  && i<3)  //sets the position of the cursor
    i++;  
  userpass[i] = uKey - '0' ;  //to get number from char !
  if(i == 3)       // if we already have 4 digits and type # -> verification
                   // if we have 4 digits and type next, we overwrite the pass  
     state = 2;
}

void verifyCode()
{
  bool correct = true;
  for(int i=0; i<=3; i++)  
   {
     if(userpass[i] != pass[i])
      {
        correct = false;
        Serial.println("We have an error");
      }
    }
      if(correct == true)
      openLock();
      else 
      closeLock();
         
state =0;      
InitPass(); // re-initializes the user pass      
}

void closeLock()
{
MyServo.write(ClosedPos); 
digitalWrite(GreenLedPin,LOW);
digitalWrite(RedLedPin,HIGH);
state = 0;
}

void openLock()
{
 MyServo.write(OpenedPos);
 digitalWrite(GreenLedPin,HIGH);
 digitalWrite(RedLedPin,LOW); 
}

void InitPass()
{
 for(int i=0; i<3; i++) userpass[i] = -1; 
}

void updateUserPass(char uKey)
{
 for(int i=0; i<3 ; i++)
    userpass[i] = userpass[i+1];
  userpass[3] = uKey - '0';
}