How to Use an RFID RC522 on Raspberry Pi

Introduction

The MFRC522 is a highly integrated reader/writer IC for contactless communication at 13.56 MHz. The MFRC522 reader supports ISO/IEC 14443 A/MIFARE mode.
The MFRC522’s internal transmitter is able to drive a reader/writer antenna designed to communicate with ISO/IEC 14443 A/MIFARE cards and transponders without additional active circuitry. The receiver module provides a robust and efficient implementation for demodulating and decoding signals from ISO/IEC 14443 A/MIFARE compatible cards and transponders. The digital module manages the complete ISO/IEC 14443 A framing and error detection (parity and CRC) functionality.

Enable Device Tree

Edit /boot/config.txt

sudo nano /boot/config.txt

Add the line below to the bottom of config.txt

device_tree=on

Hit Ctrl + O to save, and Ctrl + X to exit.

Setup SPI:

Run raspi-config

sudo raspi-config

Go through: 8 Advanced Options -> A6 SPI->Yes
Then press Enter three times to enable SPI as default settings Select finish and reboot

Install python-dev and git:

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install python-dev git

Wiring:

Name	Pin#	Pin Name
VCC	1	3V3
RST	22	GPIO25
GND	Any	Any Ground
MISO	21	GPIO9
MOSI	19	GPIO10
SCK	23	GPIO11
NSS	24	GPIO8
IRQ	None	None

Install SPI-Py

cd ~
git clone https://github.com/lthiery/SPI-Py.git
cd SPI-Py/
sudo python setup.py install

Get MFRC522-python library

cd ~
git clone https://github.com/mxgxw/MFRC522-python.git
cd MFRC522-python/

Now Run:

To read card

sudo python Read.py

To write card

sudo python Write.py

Resource

MFRC522 datasheet