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.
Solder headers to the BlueSmirf Bluetooth module.
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.
Solder headers to the ID12 breakout board.
Solder the RFID reader to the ID12 breakout board.
Hard-wire the ID12 reader to ASCII mode.
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)
Test the reader with a PC
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