#include <LiquidCrystal_I2C.h>
#include <SPI.h>
#include <MFRC522.h>
#define SS_PIN 5
#define RST_PIN 2
#define SCK_PIN 18
#define MISO_PIN 19
#define MOSI_PIN 23
MFRC522 mfrc522(SS_PIN, RST_PIN);  
LiquidCrystal_I2C lcd(0x27, 16, 2); 
 
void setup() {
  SPI.begin(SCK_PIN, MISO_PIN, MOSI_PIN);
  mfrc522.PCD_Init();
  lcd.init();
  lcd.backlight(); 
  lcd.setCursor(2, 0);  
  lcd.print("Group 2 17C");
  delay(2000);
  lcd.clear();  
}
 
void loop() {
  lcd.setCursor(0, 1);
  lcd.print("RFID Module");
  if ( ! mfrc522.PICC_IsNewCardPresent()) 
  {
    return;
  }
  if ( ! mfrc522.PICC_ReadCardSerial()) 
  {
    return;
  }
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("UID tag :");
  String content= "";
  byte letter;
  for (byte i = 0; i < mfrc522.uid.size; i++) 
  {
     Serial.print(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");
     Serial.print(mfrc522.uid.uidByte[i], HEX);
     content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));
     content.concat(String(mfrc522.uid.uidByte[i], HEX));
  }
  lcd.setCursor(0, 1);
  lcd.print("Message : ");
  content.toUpperCase();
}