#include <Keypad.h>

#define BUZZER 13 // buzzer for pin 13

const int COLUMN = 4;
const int ROW = 4;

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

byte pinRow[ROW] = {9, 8, 7, 6};
byte pinCol[COLUMN] = {5, 4, 3, 2};

Keypad keypad = Keypad(makeKeymap(keys), pinRow, pinCol, ROW, COLUMN);

int cursorColumn = 0;

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

void loop() {
  char key = keypad.getKey();
  if (key != NO_KEY){
    beep();
    Serial.println(key);
  }
}


void beep(){
  tone(BUZZER, 1000); // Generate a beep at 1000 Hz
  delay(100);
  noTone(BUZZER);
}