RFIDUIDToScren.ino

/*
 * Created by Azuxul, September 2015
 * http://azuxul.fr/
 * 
 * ---------------------------------
 * 
 * Print UID of RFID card to I2C LCD scren for nano Arduino v3
 * 
 * RFID MODULE : RFID-RC522
 * LCD : GDM1602A
 * 
 * Used library : MFRC522, LiquidCrystal
 */

#include <SPI.h>
#include <MFRC522.h>

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

LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7);   // LCD
MFRC522 mfrc522(10, 9);                             // RFID MODULE

void setup() { // Init

  SPI.begin();               // Init SPI bus
  mfrc522.PCD_Init();        // Init MFRC522 card

  lcd.begin(16, 2);         // Init lcd

  // Print txt to LCD
  lcd.setCursor(0, 0);
  lcd.print(" -- RFID UID --");
  
  lcd.setCursor(0, 1);
  lcd.print("     Azuxul    ");
}

void loop() { // Loop start

  if ( ! mfrc522.PICC_IsNewCardPresent() || ! mfrc522.PICC_ReadCardSerial() ) { // If no card -> return
    return;
  }

  lcd.clear(); // Clear LCD

  // Print text to LCD
  lcd.setCursor(0, 0);
  lcd.print("...");

  String uid = ""; // UID
    
  for (byte i = 0; i < mfrc522.uid.size; i++) { // Get UID
    
    uid += String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");
    uid += String(mfrc522.uid.uidByte[i], HEX);
  } 
  
  uid.remove(0, 1); // Remove first char (equals to " ")
  uid.toUpperCase();
  
  lcd.clear(); // Clear LCD

  // Print text to LCD
  lcd.setCursor(0, 0); 
  lcd.print("RFID card UID :");

  lcd.setCursor(0, 1);
  lcd.print(uid);

  // Add delay
  delay(500);

}  // Loop end