Weather Proof, Bluetooth Capable RFID Reader




Introduction: Weather Proof, Bluetooth Capable RFID Reader

This instructable connects the popular BlueSmirf Bluetooth module to the ID12 RFID reader and shows how to make a dust and water resistant (IP55) RFID reader that sends IDs to your PC or mobile phone over Bluetooth radio without an additional micro controller and without an external power source. Created as a prototype for an online swim lap counter system named Rfish, it can be used for any project in need of a self contained, weather proof RFID reader.



  • Cutter
  • Soldering iron
  • Helping hands

Step 1: Solder Headers to the BlueSmirf Bluetooth Module

Step 2: Configure the BlueSmirf Module Via USB

Connect the BlueSmirf to the USB to serial adapter as follows (you might use headers to connect female jumper cables to the female connector of the USB to serial adapter):

  • VCC to 3.3V
  • GND to GND
  • TX-O to RX-I
  • RX-I to TX-O

Then plug the USB into your PC (the following instructions apply to Windows XP and might differ for other operating systems). The red LED on the BlueSmirf should now blink.

Press "-R" on your keyboard to open the "Run" command line, type "devmgmt.msc" and press "". This opens the Device Manager. Open the node "Ports (COM & LPT)" in the device tree. There should be a node called "USB Serial Port (COM)" e.g. COM17. Write down the COM port number (to talk to the BlueSmirf module over USB we will open a connection to this COM port).

Download (requires .NET 2.0; source included for educational purpose) and unzip it.

Edit SerialUsbBlueSmirfConfig.bat (right click, "Edit") to match your COM port number and baud rate (default for BlueSmirf Gold is 115200 baud) and save the changes.

Start SerialUsbBlueSmirfConfig.bat and as soon as the program displays your COM port in the command shell, type the following commands (BlueSmirf's response shown in italic):

  • $$$
  • CMD
  • SU,96
  • AOK
  • ---
  • END

When in command mode, the BlueSmirf's red LED starts to flash faster. After leaving command mode, the BlueSmirf Bluetooth module is set to 9600 baud which is necessary to communicate with the ID12 RFID reader.

(Note: If you want to use SerialUsbBlueSmirfConfig.bat again don't forget to change it to 9600.)

Step 3: Solder Headers to the ID12 Breakout Board

Step 4: Solder the RFID Reader to the ID12 Breakout Board

Step 5: Hard-wire the ID12 Reader to ASCII Mode

Solder the two short wires as follows:

  • Red wire from 5V (11) to /RST (2)
  • Black wire from FS (7) to GND (1)

Step 6: Connect the BlueSmirf to the ID12 Reader and 3 1.5V AA Batteries

Connect the BlueSmirf to the ID12 reader as follows:

  • VCC to 5V (11)
  • GND to GND (1)
  • RX-I to D0 (9)

Then connect the ID12 to the batteries:

  • 5V (11) to + (Plus)
  • GND (1) to - (Minus)

If you use solder to create a durable connection it might be better to unplug the jumper cable before soldering. Also, the jumper cable's plastic cover melts really quick so take care not to heat it too long.

Once you got the connections ready, attach 3 1.5V AA batteries (equals 4.5V) and make shure the BlueSmirf starts to flash its red LED.

Note: While the BlueSmirf is marked as 3.3V it does work pretty well with 4.5V. The ID12 which is laid out for 5V also functions with 4.5V (maybe with a slightly lower range).

Put everything into the box and try to close it tightly without squeezing any cables. For the following test (next step) you might want to open the box again to be sure the BlueSmirf LED works as supposed.

Step 7: Test the Reader With a PC

To test the reader you need a PC with Bluetooth and a test program.

Download (requires .NET 2.0; source included for educational purpose) and unzip it.

Pair your PC with the BlueSmirf:

  • Enable Bluetooth on your PC
  • Disconnect and then reconnect the BlueSmirf to the batteries (inquiry only works right after module startup)
  • Start Bluetooth inquiry on your PC
  • Select the device called "FireFly ..."
  • Enter the PIN 1234
  • Choose "Serial Profile" or SPP or similar, without (!) encryption
  • Write down the COM port number of the serial Bluetooth connection on your PC

Edit Serial.bat (right click, "Edit") to match your COM port number and baud rate (must be 9600 baud) and save the changes.

Start Serial.bat and wait for the BlueSmirf's LED to turn green. This does only work if you connect to the right Bluetooth serial COM port (not the same COM port as in step 2).

Once the LED is green you can start scanning RFIDs. Hold the RFID tag very close to the front of the reader (i.e. the top of the case) and you should see the read IDs being displayed on the PCs console shell, maybe with some additional characters.

Congrats - you're done.

(Note: if you see questionmarks instead make shure your batteries are fully loaded and check the wiring in step 5.)



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97 Discussions

Great project man! I have a question, what readind range would it have if you were to use it without the case?

1 reply

Not much better, I fear. This RFID module is very short range.

Hi Bubacar, thanks for the link. Your product looks very nice and kid-friendly! I don't sell the reader right now, sorry.

One more question (for the time being): Can I use 1.5v button cells to make this work? Obviously it won't have the life of the AAs but would it work at all? And I don't suppose you know if there's a battery case designed for three 1.5v button cells?

1 reply

Not sure. Google Bluetooth Low Energy or BLE for something using less energy. There are probably also low power RFID readers, e.g. the one used by (a toy to swap contacts, at least they used to do that).

Some of the software links appear to be dead. Where can I obtain the software needed for this?

3 replies

Should be fixed now. Thanks for letting me know.

This link still appears dead:

Maybe a caching issue. Just add www. in front of

Is there a program that would allow this to make the phone vibrate when different RFIDs were present? So you could have RFIDs numbered and each one would cause a series of vibrations?

1 reply

You could use this Android API to vibrate in a pattern:

Great article still I wanted to know can we use any other bluetooth module instead of bluesmirf gold bluetooth module

1 reply

Sure, you can use any other Bluetooth module that provides the Serial Protocol. Cheers, Thomas website seems to be down..

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