Reading RFID Tags with an Arduino

In this project, you'll learn to read an RFID tag using the Innovations ID-12 reader and an Arduino Duemilanove.

Step 1 Let's Get Started!

We'll be using the ID Innovations ID-12 to perform the task of reading an RFID tag. At a minimum, it requires +5V, ground, and a digital pin (on the Arduino) that we will utilize for serial communication.

The ID-12 operates at 9600bps and has an LED output pin. This LED output is great! We can use this to verify if the ID-12 is reading the tag even before it is connected to the Arduino!

The ID-12 has unusual pin spacing. Pick up the breakout board from SparkFun (SEN-08423 ) to make it easily fit on your breadboard.

All of ID Innovations readers read at a frequency of 125 kHz. Any 125 kHz RFID tag will do.

Comments

[nilved]

I have never worked with RFID but I think its awesome and I'd like to start working with it how much do they cost and where can I get them?

[MrkTrussell]

Look in the text on Step 1. Both the "ID Innovations ID-12" and the breakout board (SEN-08423) are hyperlinks. Follow the links to SparkFun where you can purchase them.

[drBen]

Hi, Is it possible to connect more than one RFID reader?
I am looking for a solution for 20-30 readers and the Information which RFID Key was hold on which Reader.

[MrkTrussell]

20-30 readers reporting to 1 Arduino is probably out of the question, but you can use more than one by implementing the SoftwareSerial library which allows multiple serial connections at once utilizing the Arduino's digital i/o pins.

Suggested Reading: http://www.arduino.cc/en/Tutorial/SoftwareSerial

[drBen]

Thanks.
What about the Arduino Mega with 54 digital input/output pins?
If i understand you right, with the software serial solution i can define 2 digital pins as an serial data connection.
With a Mega Board this is a possibility of 27 RFID Readers.
Right?

[MrkTrussell]

I haven't experimented with multiple serial devices. I would assume that any Arduino would be overwhelmed trying to read ~27 incoming bits simultaneously in a few microseconds (worst case scenario = all readers operating at once).

Handling asynchronously received data from multiple serial devices turns out to be a difficult task.

One would need to implement a way to only read a device which is active and assign priorities when two or more devices are active at the same time.

[drBen]

ok... difficult...

[MrkTrussell]

Then again, maybe the Arduino can handle it.

To quote the SoftwareSerial tutorial, "The software serial connection can run at 4800 baud or 9600 baud reliably."

It does not list a maximum number of connected devices. One would have to experiment to see if it could work.

[Robot Lover]

I meant parallax RFID reader

[Robot Lover]

Great project! I have only used the parallax RFID tag. Maybe I should purchase one of these. Thanks for the great instructable!