Hriday 7A : RFID Smart Attendance system

 #include <SPI.h>

#include <MFRC522.h>

#include <Wire.h>

#include <LiquidCrystal_I2C.h>

// LCD: I2C address 0x27, 16 columns, 2 rows

LiquidCrystal_I2C lcd(0x27, 16, 2);

// RFID module pins

#define SS_PIN 10

#define RST_PIN 9

MFRC522 rfid(SS_PIN, RST_PIN);

// Hriday's RFID UID (change based on your actual card)

byte hridayUID[] = {0x5A, 0xAC, 0x10, 0x5}; // Example UID

void setup() {

  Serial.begin(9600);

  SPI.begin();

  rfid.PCD_Init();

  lcd.begin(16, 2);

  lcd.backlight();

  Serial.println("RFID Attendance System Ready");

  lcd.setCursor(0, 0);

  lcd.print("Scan your card");

}

void loop() {

  // Check if a new card is present

  if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) {

    return;

  }

  Serial.print("Scanned UID: ");

  for (byte i = 0; i < rfid.uid.size; i++) {

    Serial.print("0x");

    Serial.print(rfid.uid.uidByte[i], HEX);

    if (i < rfid.uid.size - 1) Serial.print(", ");

  }

  Serial.println();

  // Compare UID with Hriday's UID

  if (checkUID(rfid.uid.uidByte, rfid.uid.size, hridayUID, sizeof(hridayUID))) {

    lcd.clear();

    lcd.setCursor(0, 0);

    lcd.print("Name: Hriday");

    lcd.setCursor(0, 1);

    lcd.print("Class 7A present Today");

    Serial.println("Attendance marked: Hriday - Class 7A");

  } else {

    lcd.clear();

    lcd.setCursor(0, 0);

    lcd.print("Unknown Card");

    Serial.println("Unknown card scanned.");

  }

  delay(3000); // Wait before allowing next scan

  lcd.clear();

  lcd.setCursor(0, 0);

  lcd.print("Scan your card");

  rfid.PICC_HaltA();        // Stop reading

  rfid.PCD_StopCrypto1();   // Stop encryption

}

bool checkUID(byte *uid, byte uidSize, byte *targetUID, byte targetSize) {

  if (uidSize != targetSize) return false;

  for (byte i = 0; i < uidSize; i++) {

    if (uid[i] != targetUID[i]) return false;

  }

  return true;

}

Pin descriptin:

Component	Arduino Pin	Notes
RC522 RFID
SDA (SS)	10	SPI slave select
SCK	13	SPI clock
MOSI	11	SPI Master Out Slave In
MISO	12	SPI Master In Slave Out
RST	9	Reset pin
3.3V	3.3V	Do NOT use 5V (may damage RC522)
GND	GND	Ground
I2C LCD
SDA	A4	I2C Data
SCL	A5	I2C Clock
VCC	5V	Power supply
GND	GND	Ground