/*
 * MFRC522 - Library to use ARDUINO RFID MODULE KIT 13.56 MHZ WITH TAGS SPI W AND R BY COOQROBOT.
 * The library file MFRC522.h has a wealth of useful info. Please read it.
 * The functions are documented in MFRC522.cpp.
 *
 * Based on code Dr.Leong   ( WWW.B2CQSHOP.COM )
 * Created by Miguel Balboa (circuitito.com), Jan, 2012.
 * Rewritten by Søren Thing Andersen (access.thing.dk), fall of 2013 (Translation to English, refactored, comments, anti collision, cascade levels.)
 * Extended by Tom Clement with functionality to write to sector 0 of UID changeable Mifare cards.
 * 
 * Released into the public domain.
 *
 * This sample shows how to fix a UID changeable MIFARE cards that have a corrupted sector 0.
 * 
 ----------------------------------------------------------------------------- empty_skull 
 
 - Aggiunti pin per arduino Mega
 - Scritto semplice codice per la scrittura e lettura 
 
 - add pin configuration for arduino mega
 - write simple read/write Code for new entry user
 
 http://mac86project.altervista.org/
 
 ----------------------------------------------------------------------------- Nicola Coppola
 * Pin layout should be as follows:
 * Signal     Pin              Pin               Pin
 *            Arduino Uno      Arduino Mega      MFRC522 board
 * ------------------------------------------------------------
 * Reset      9                5                 RST
 * SPI SS     10               53                SDA
 * SPI MOSI   11               51                MOSI
 * SPI MISO   12               50                MISO
 * SPI SCK    13               52                SCK
 *
 * The reader can be found on eBay for around 5 dollars. Search for "mf-rc522" on ebay.com. 
 */

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

#define SS_PIN 10
#define RST_PIN 9

MFRC522 mfrc522(SS_PIN, RST_PIN);        // Create MFRC522 instance.
MFRC522::MIFARE_Key key;

void setup() {
        Serial.begin(9600);        // Initialize serial communications with the PC
        SPI.begin();                // Init SPI bus
        mfrc522.PCD_Init();        // Init MFRC522 card
        Serial.println("Warning: this example clears your mifare UID, use with care!");
        
        // Prepare key - all keys are set to FFFFFFFFFFFFh at chip delivery from the factory.
        for (byte i = 0; i < 6; i++) {
                key.keyByte[i] = 0xFF;
        }
}

void loop() {
    if ( mfrc522.MIFARE_UnbrickUidSector(false) ) {
      Serial.println("Cleared sector 0, set UID to 1234. Card should be responsive again now.");
    }
    delay(1000);
}