Interfacing RFID with Arduino

Table of Contents

NOTE: If you don’t know about RFID system (TAG, Module/ Reader) or working mechanism, you can go through the links before reading this article about Interfacing RFID with Arduino.

RFID tags have similar applications to barcodes in that (barcodes) data from a tag are captured by a device that stores the data in a database. RFID, though, has more than a few advantages over barcode asset tracking software.

Most importantly data of the RFID tag can be read outside the LOS (line-of-sight), whereas Bar-codes stickers must be made straight against an optical scanner to decode/read.

EM18 RFID PINS CONFIGURATION

EM-18 is a nine pin device. Among nine pins, 2 pins are not connected, so we basically have to consider seven terminals.

Pin Number	Description
VCC	Connect to the positive of power source.
GND	Connected to the ground.
BUZZ	Connect to BUZZER if used
NC	No Connection
NC	No Connection
SEL	SEL=1 then o/p =RS232 SEL=0 then o/p=WEIGAND
TX	DATA send through TX using RS232 communication
DATA1	WEIGAND interface DATA HIGH pin
DATA0	WEIGAND interface DATA LOW pin

CIRCUIT DIAGRAM INTERFACING RFID READER WITH ARDUINO

RFID ARDUINO CODE

PROGRAM: READ RFID TAG ID AND PRINT IT ON SERIAL MONITOR

String id;
void setup() {
  Serial.begin(9600);
}

void loop() {
  if (Serial.available() > 0) {
    id = Serial.readString();
    Serial.println(id);
    delay(1000);
  }
}

This is the same code we used for Bluetooth devices but here we will receive 12 character string of RFID tag information.

Serial.readString() will give us serial data present and it is stored in “String id”. Then print it on Serial Monitor and note it somewhere for later use.