//explanation keypad: https://deepbluembedded.com/esp32-keypad-lcd-example-arduino/
// https://arduinogetstarted.com/tutorials/arduino-keypad#content_about_keypad

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

//Í2C Adress and column and line defintion of de LCD
#define I2C_ADDR    0x27
#define LCD_COLUMNS 20
#define LCD_LINES   4

// create LCD-object
LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

// define matrix of the keyboard
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns

// define keyboard layout
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

// define input ports for keyboard
byte rowPins[ROWS] = {23, 12, 3, 13}; 
byte colPins[COLS] = {19, 18, 5, 17};

// create keyboard-object
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);



void setup() {
  Serial.begin(115200);
  // init (start) LCD
  lcd.init();
  // Turn on the backlight on LCD.
  lcd.backlight();
  // print the Message on the LCD. 
  lcd.print("Keyboardeingabe:");

  Serial.println("ESP32 Keyboard connection");
}

void loop() {
  delay(10); // this speeds up the simulation

  // get keyboard input
  char key = keypad.getKey();

  //output on LCD and console
  if (key){
    lcd.setCursor (0, 1);
    lcd.print (key);
    Serial.println(key);
  }
}