SBMM

#include <LiquidCrystal.h>

const int rs = 8, en = 9, d4 = 4, d5 = 5, d6 = 6, d7 = 7;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

unsigned short secunde, miliSecunde, minute, ore;
unsigned long int k=0;

void setup()
{
  DDRD|=0xFF;
  lcd.begin(16, 2);
  TIMSK2=0x01; // validare intrerupere de la Timer 0 Overflow
  TCCR2A=0x00; // setare mod normal
  TCCR2B=0x06;


}
void Print0(unsigned short nr){
 if(nr < 10) lcd.print('0');
}

void loop(){
  Print0(ore);
  lcd.print(ore);
  lcd.print(':');
  Print0(minute);
  lcd.print(minute);
  lcd.print(':');
  Print0(secunde);
  lcd.print(secunde);

  delay(1000);
  lcd.clear();
}

ISR(TIMER2_OVF_vect){
    k++;
  if(k == 240){
    ++secunde;
     k =0;
  }
  if(secunde > 59){
    ++minute;
    secunde = 0;
  }
  if(minute > 59){
   ++ore;
    minute = 0;
  }
  if(ore == 24) ore = 0;
}