#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;

char keys[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};    


const byte ledPin = 13;

Keypad klavesnica = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

void setup() {
 Serial.begin(9600);
 pinMode(ledPin, OUTPUT); 
}

void loop() {
 char key = klavesnica.getKey();
 if (key) {
   Serial.println(key);  
   if (key == '1') {
     digitalWrite(ledPin, LOW); 
   } else if (key == '2') {
     digitalWrite(ledPin, HIGH); 
   }
 }
}