Fareed Mohmed← All projects

Arduino project · Smart doors and home · Easy

RFID Guest and Owner Lights

The owner card lights green and the guest card lights yellow.

What you will learn

  • How each card has its own number
  • How to treat people differently
  • How hotels and offices use cards

How it works

Card A lights the green LED, card B lights the yellow LED. Each light goes off when the card is gone.

Try this next

  • Add a different sound for each card.
  • Allow the guest only in daytime.
  • Show the name on an LCD.

The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.

1Choose your Arduino board
2Build the circuit
Parts: sensors and actuators (tap to show or hide)

Try the inputs (virtual sensors)

Pins (you can change them)

PartArduino pin (change it here)How to wire it

Every wire, one by one

Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.

#ColourFrom (part and leg)To
3Define the sequence

Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.

4Arduino code

5Parts list and where to buy

Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.

#ItemQtySearch termBuy / compare
6Export

The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.

7Learn: do’s, don’ts, cautions and tips

In the real world

Owner and guest at the front door

Pick card A or card B in the simulator. Either known card opens the door; an unknown card leaves it locked with the red lamp on.

Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.