The total cost for building this RFID attendance system using Arduino is approximately $25-35, including Arduino Uno ($15), MFRC522 RFID module ($5), RTC module ($3), I2C LCD ($5), RFID cards ($2), ...

Create a new folder called "LiquidCrystal_I2C" under the folder named "libraries" in your Arduino sketchbook folder. Create the folder "libraries" in case it does not exist yet. Place all the files in ...