The model of RFID reader used here is RFID reader 232N (RFID-IDR-232N) which actually can be connected to PC directly through RS232 using the DB9 (Male) of its cable for sending tag’s IDs scanned to computer.Somehow, the establishment of a wireless RFID reader enable the RFID reader to be place a t a further distance from the PC since the cable length constraint is eliminated but still can sends the tag’s IDs scanned to PC through the wireless link. This consequently improve the RFID reader portability. The wireless module used in this project is XBee. In order to simplify the process of setting up the circuit of wireless RFID reader, XBee Starter Kit, SKXBEE (with XBee module) is used instead since it consists of onboard logic shifter that allow UART communication with 5V device while XBee is 3.3V device and RS232 chip combined USB port that allow direct communication between computer and XBee. Bascally, the concept of wireless RFID reader can be illustrated by the flow diagram below.
Figure 1: Flow diagram of wireless RFID reader
As seen from Figure 1, the USB (Male) of RFID reader cable will be connected to 5V supply output of Breadboard Power Stick 5V 3v3 (BPS-5-3) through using a Breakout USB Type A Female (BB-USB-AR) so it will be power up when the wireless RFID reader circuit is turn on (by turn on the power adapter DC 12V connected to BPS-5-3). While, SKXBEE#1 (with XBee #1) is connected to PC with direct communication between them using USB cable. The RFID reader is also connected to wireless RFID circuit through Female RS232 cable and UART to RS232 converter (URS232A). The wireless RFID circuit contains SKXBEE# 2 (with XBee #2).
When the ready connected circuit is power up, pre-configured XBee#1 and XBee#2 will associate with each other to establish wireless link for communication. Also, the RFID reader is ready to scan the RFID card (which contains 10 digit ID stored electronically inside it). The ID info will be read by RFID reader, and then transmitted to XBEE#2 through URS232A. Next, through the wireless link, the ID info will be sent from XBee #2 to XBee #1. As the XBee #1 received the ID info, it will send it to hyperterminal of PC for displaying. Amazing, isn’t it? Well, let’s start!!
Figure 2Wireless RFID full circuit.
