RFID Computer login

I wanted a simple way of quickly logging on to my computer without having to typing my password in and did not want to have no security either.

RFID Computer login

There are various products on the market that would solve this problem from fingerprint readers to proximity dongles but i decided to see what i could knock up with parts i mainly already had.

Looking in my micro stuff i had a RC522 RFID tag reader 3.3v :

Also an 3.3v arduino Leonardo clone aswell based on a sparkfun pro micro which also can act as a USB device such as a keyboard. This is useful as if a 5v arduino was used a level shifter would be required due to the RC522 not being 5v torrent.

How it works

When the chosen cards is presented the arduino will act as a keyboard and simply type the stored password in followed by a carriage return .


As mentioned, both devices being the same voltage ,3.3v made wiring so easy !.


I used the Arduino library for MFRC522 by Miguel Balboa , so you will need to add this library to arduino.
Please note this is only a very basic example and the password is stored in plain text in your arduino document ,  so this is very much proof of concept and has just been thrown together. It may also be a good idea after uploading to arduino to and save your arduino document with the password blank.

UPDATE!  Please also see RFID Login software Update ! for the latest software example .



How to use

1) First Set “#define enable_serial” = 1  to enable serial output.
2) Open a serial terminal with 9600 baud
3) Swipe a card and make a note of  UIDs .
4) Add recorded card UID to line 27.
5) Add login information to the keyboard section line 113 , modify the key squence for other OS’s and applications .

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