RFID control system

RFID Control System – Using Arduino and RC522 In this project, we will use an RFIDRC522 module with an Arduino Uno to control access based on RFID tags. When an authorized tag is scanned, a green LED lights up. If an unauthorized tag is scanned, a red LED blinks for 5 seconds to indicate access denial.

Components Required

• 1. Arduino Uno
• 2. RFID RC522  Module
• 3. Two RFID Tags (13.56  MHz frequency)
• 4. RGB LED 
• 5. Resistors (220Ω)
• 6. Jumper Wires

Circuit Connections

Below is the connection setup for our RFID-based access control system:

 

Component	RFID Module	Arduino Uno
VCC	3.3V	3.3V
RST	RST	Pin 9
GND	GND	GND
MISO	MISO	Pin 12
MOSI	MOSI	Pin 11
SCK	SCK	Pin 13
SDA	SDA	Pin 10

Arduino Code for RFID Access System

Below is the complete Arduino code for this RFID-based system. 

#include <SPI.h>
#include <MFRC522.h>

#define RST_PIN 9
#define SS_PIN 10
#define GREEN_LED 7
#define RED_LED 8

MFRC522 mfrc522(SS_PIN, RST_PIN);
byte authorizedUID[] = {0xC3, 0x64, 0x45, 0xDA}; // Authorized Tag

void setup() {
  Serial.begin(9600);
  SPI.begin();
  mfrc522.PCD_Init();
  pinMode(GREEN_LED, OUTPUT);
  pinMode(RED_LED, OUTPUT);
  Serial.println("Scan an RFID tag...");
}

void loop() {
  if (!mfrc522.PICC_IsNewCardPresent()) return;
  if (!mfrc522.PICC_ReadCardSerial()) return;

  Serial.print("Card UID: ");
  bool authorized = true;
  for (byte i = 0; i < mfrc522.uid.size; i++) {
    Serial.print(mfrc522.uid.uidByte[i], HEX);
    Serial.print(" ");
    if (mfrc522.uid.uidByte[i] != authorizedUID[i]) {
      authorized = false;
    }
  }
  Serial.println();

  if (authorized) {
    Serial.println("Authorized Access: Welcome, CREATOR!");
    digitalWrite(GREEN_LED, HIGH);
    delay(2000);
    digitalWrite(GREEN_LED, LOW);
  } else {
    Serial.println("Unauthorized Access: ERROR!");
    for (int i = 0; i < 5; i++) {
      digitalWrite(RED_LED, HIGH);
      delay(500);
      digitalWrite(RED_LED, LOW);
      delay(500);
    }
  }
}

How It Works?

 1️⃣ Place the RFID tag near the RFID reader. 

 2️⃣ If the tag is authorized, the green LED turns ON for 2 seconds.

 3️⃣ If the tag is unauthorized, the red LED blinks for 5 seconds.

Applications of RFID Control System

 ✅ Security Systems – Used in offices, homes, and industries. 

 ✅ Access Control – Allows only authorized personnel to enter. 

 ✅ Attendance System – Used in schools and workplaces. 

 ✅ Automated Toll Booths – Used for vehicle identification. 

~by CREATOR