RFID Reader and Writer

Overview

RFID(Radio Frequency Identification) cards are like an electric key to unlock and lock things by holding unique data. For example, your credit card is an RFID card if it has the contact-less payment option.
This can be used, in my case for switching things on and off or unlocking something. We will be using the RFID-RC522 board for this project. You can buy it here.

What to Do:

1. Firstly, we need to wire it up to the pi. (Pin numbers):

  • SDA
  • SCK
  • MOSI
  • MISO
  • GND
  • RST
  • 3.3V
  • -
  • -
  • -
  • -
  • -
  • -
  • -
  • 24
  • 23
  • 19
  • 21
  • 6
  • 22
  • 1

2. We need to enable the SPI interface for the pi. Do this by running he following command going to interfaces > SPI > enable > finish.

$ - sudo raspi-config

3. Reboot the Pi

$ - sudo reboot

4. Check that the spi_bcm2835 module is loaded. If it is it should appear under this command when we run it.

$ - lsmod | grep spi

5. Next, install python2.7-dev.

$ - sudo apt-get install python2.7-dev

6. Next, download and install SPI-Py using the following commands.

$ - git clone https://github.com/fraser148/SPI-Py.git

$ - cd SPI-Py

$ - sudo python setup.py install

7. Install MFRC522-python

$ - git clone https://github.com/fraser148/MFRC522-python.git

To read a card there is some example code called "Read.py" in the MFRC552-python folder. Run this and it will display the data held on the card.

I adapted this code to turn on and off a camera. Look at my tutorial to see how I did it. The code was very difficult to understand at first but I managed to make it suit my needs.