For details and code follow link:
thanks for http://www.dronmarket.com for sponsoring me.
http://forum.arduino.cc/index.php?topic=256260
Arduino RC522 RFID Door Unlocker
* July/2014 Omer Siar Baysal
*
* Unlocks a Door controls a relay actually
* using a RC522 RFID reader with SPI interface on your Arduino
* You define a Master Card which is act as Programmer
* then you can able to choose card holders who able to unlock
* the door or not.
*
* Easy User Interface
*
* Just one RFID tag needed whether Delete or Add Tags
* You can choose to use Leds for output or
* Serial LCD module to inform users. Or you can use both
*
* Stores Information on EEPROM
*
* Information stored on non volatile memory to preserve
* Users’ tag, Master Card ID will be hard coded on Arduino’s Flash
* No Information lost if power lost. EEPROM has unlimited
* Read cycle but 100,000 limited Write cycle.
*
* Security
*
* We are going to use Tag’s Unique IDs, But since this module
* and Tags are cheap, I guess their IDs not so Unique.
*
* I think it is not secure to only use Tags’ UID
* to verify Tags’ users who want to unlock a door.
*
* MFRC522 Library also lets us to use some authentication
* mechanism, writing blocks and reading back
* and there is great example piece of code
* about reading and writing PICCs
* here http://makecourse.weebly.com/week10segment1.html
*
* If you serious about coding and security
* you should really check Mıfare’s datasheet
* We are going to use completely INSECURE way to
* Unlock a door.
*
* And there is a note on Datasheet which mentions aboout that
* Note: The use of Single Size UIDs unique ones might end soon,
* since the number of usable IDs is limited to approximately
* 3.7 billion pieces only.
*
* If you rely on heavy security, figure it out how RFID system
* can be secure yourself personally very curious about it
*
* Also there are always security
* issues if there is a “LOCK” actually.
*
* Credits
*
* Omer Siar Baysal who put together this project
*
* Idea and most of code from Brett Martin’s project
* http://www.instructables.com/id/Arduino-RFID-Door-Lock/
* www.pcmofo.com
*
* MFRC522 Library from miguelbalboa
* https://github.com/miguelbalboa/rfid
*
* Arduino Forum Member luisilva for His Massive Code Correction
* http://forum.arduino.cc/index.php?topic=257036.0
* http://forum.arduino.cc/index.php?action=profile;u=198897
*
* License
*
* You are FREE what to do with this code
* Just give credits who put effort on this code
*
* “PICC” short for Proximity Integrated Circuit Card aka RFID Tags
- Post Time: 02-15-17 - By: http://www.rfidang.com