#include <LiquidCrystal_I2C.h>
#include <Keypad.h>
LiquidCrystal_I2C lcd(0x27,16,2);
const byte radky = 4;
const byte sloupce = 4;
char klavesy [radky] [sloupce] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'},
};
byte pinyRadku [radky] = {12,11,10,9};
byte pinySloupcu [sloupce] = {8,7,6,5};

Keypad Klavesnice = Keypad (makeKeymap(klavesy), pinyRadku, pinySloupcu, radky, sloupce);

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.setCursor(2,0);
  lcd.print("Je stisknuto:");
  Serial.begin(9600);

}

void loop() {
  char klavesa = Klavesnice.getKey();
  if (klavesa){
    lcd.setCursor(8,1);
    lcd.print(klavesa);
  }

}