#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

const byte numROWS = 4;
const byte numCOLS = 4;

char keymap [numROWS] [numCOLS] = {

  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}

};

byte rowPins [numROWS] = {0,1,2,3};
byte colPins [numCOLS] = {4,5,6,7};

Keypad myKeypad = Keypad(makeKeymap(keymap), rowPins, colPins, numROWS, numCOLS);

void setup() {
  // put your setup code here, to run once:
  lcd.begin(1, 2, 1);
  Serial.begin(9600);
  lcd.home();
}

void loop() {
  // put your main code here, to run repeatedly:
  char keyPressed = myKeypad.getKey();
  if (keyPressed != NO_KEY) {
    Serial.print(keyPressed);
    lcd.print(keyPressed);
  }

}