#include <LiquidCrystal.h>
LiquidCrystal lcd(12,11,10,9,8,7);

void Initkpm()
{
  pinMode(6,OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(3,OUTPUT);
  pinMode(2,INPUT_PULLUP);
  pinMode(1, INPUT_PULLUP);
  pinMode(0, INPUT_PULLUP);
  pinMode(13, INPUT_PULLUP);
}
void setup() {
  // put your setup code here, to run once:
  
  lcd.begin(8,2);
  Initkpm();
  lcd.setCursor(0,0);
  lcd.print("KEYPAD PRESS");
}

unsigned int kpmLUT[4][4]=
{
  {0,1,2,3},
  {4,5,6,7},
  {8,9,10,11},
  {12,13,14,15}
};
unsigned int ColScan(void)
{
  unsigned int t;
  t=digitalRead(2)&digitalRead(1)&digitalRead(0)&digitalRead(13);
  return t; 
}
unsigned int RowCheck(void)
{
  unsigned int rNO;
  while(ColScan());
  digitalWrite(6,LOW);
  digitalWrite(5,HIGH);
  digitalWrite(4,HIGH);
  digitalWrite(3,HIGH);
  if(ColCheck()==0)
      rNO=0;

  digitalWrite(6,HIGH);
  digitalWrite(5,LOW);
  digitalWrite(4,HIGH);
  digitalWrite(3,HIGH);
  if(ColCheck()==0)
      rNO=1;

  digitalWrite(6,HIGH);
  digitalWrite(5,HIGH);
  digitalWrite(4,LOW);
  digitalWrite(3,HIGH);
  if(ColCheck()==0)
      rNO=2;     

  digitalWrite(6,HIGH);
  digitalWrite(5,HIGH);
  digitalWrite(4,HIGH);
  digitalWrite(3,LOW);
  if(ColCheck()==0)
      rNO=3;

    return rNO;       
}
unsigned int ColCheck(void)
{
  unsigned int cNO;
  if(digitalRead(2)==0)
     cNO=0;

  if(digitalRead(1)==0)
    cNO=1;

  if(digitalRead(0)==0)
    cNO=2;

  if(digitalRead(13)==0)
  cNO=3;

  return cNO;       
}
unsigned int KeyScan(void)
{
  unsigned int rNO,cNO;
  rNO=RowCheck();
  cNO=ColCheck();
  while(ColScan()==0);

  return kpmLUT[rNO][cNO];
}

unsigned int keyvalue;
void loop() {
  // put your main code here, to run repeatedly
   // keyvalue=KeyScan();
    lcd.setCursor(0,1);
    lcd.print("hello");
    lcd.print(keyvalue);
    lcd.setCursor(0,1);
    lcd.print("  ");
}