#include <Keypad.h>
#include <LiquidCrystal.h>

/* Keypad */
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 pinesROWS[ROWS] = {23, 25, 27, 29};
byte pinesCOLS[COLS] = {31, 33, 35, 37};

Keypad keyboard = Keypad(makeKeymap(keys), pinesROWS, pinesCOLS, ROWS, COLS);
/* Keypad */

/* LiquidCrystal */
LiquidCrystal lcd(39, 41, 43, 45, 47, 49);
/* LiquidCrystal */

char KEY;
const char ZERO = '0';

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

  lcd.begin(16, 2);
  lcd.print("test!");
}

void loop() {
  // put your main code here, to run repeatedly:
  KEY = keyboard.getKey();
  if(KEY != NULL) {
    if(isNum(KEY)) {
      int num = KEY - ZERO;
      // Serial.print(num);
      lcd.setCursor(0, 1);
      lcd.println(num);
    } else {
      lcd.setCursor(0, 1);
      lcd.println(KEY);
    }
  }
}

int isNum(char value) {
  return value != 'A' && value != 'B' && value != 'C' && value != 'D' && value != '*' && value != '#';
}