Read RFID card Data using Micro:bit board and RFID-RC522

Tutorial plan

1- Purpose of the tutorial

2- RFID-RC522 module and RFID card

3- Connecting Micro:bit board with RFID-RC522 module and LCD I2C Screen

4- Makecode code to Read RFID Card and Display on LCD

Purpose of the tutorial

The purpose of reading RFID card data using a Micro:bit board and an RFID-RC522 module to display the ID of the RFID card on an LCD I2C display is to create an identification system with a visual output. This can be used for:

1. Access Control & Authentication – Displaying the card ID when a user scans an RFID tag for security or authorization.

2. Attendance Tracking – Showing the ID of a student, employee, or visitor on the LCD when they scan their card.

3. Inventory & Asset Management – Identifying objects or products by displaying their unique RFID ID on the LCD.

4. Event Registration – Verifying attendees by scanning their RFID badges and showing their IDs.

5. Cashless Transactions (Simulation) – Displaying card IDs for a prototype payment system.

RFID-RC522 module and RFID card

1) RFID-RC522 module

The RFID-RC522 is a low-cost RFID (Radio-Frequency Identification) module that operates at 13.56 MHz and is commonly used for reading and writing RFID tags and cards. It communicates with microcontrollers like Micro:bit, Arduino, and ESP32 using the SPI, I2C, or UART communication protocols.

How It Works ?

1. The Micro:bit sends a signal to the RFID-RC522 module to check for a nearby RFID card.

2. When a card is detected, its Unique Identifier (UID) is read.

3. The Micro:bit processes the UID and can display it on an LCD I2C display, print it to the serial monitor, or trigger an event.

2- RFID badge :

An RFID badge is a contactless smart card that contains an embedded RFID chip and an antenna. It is commonly used for identification, access control, attendance tracking, and payment systems. When placed near an RFID reader (like the RC522 module), the badge transmits its Unique Identifier (UID) wirelessly using radio-frequency communication.

How an RFID Badge Works with the RC522 Module

1. The RFID badge contains a chip with a UID (Unique Identifier).

2. When placed near the RFID-RC522 module, the module energizes the badge using electromagnetic waves.

3. The badge transmits its UID back to the reader via radio signals.

4. The Micro:bit receives and processes the UID, displaying it on an LCD I2C display or sending it to another system.

3- RFID white card

An RFID white card is a blank, contactless RFID card that contains an embedded RFID chip and antenna. It is often used for identification, security access, attendance tracking, and cashless payments. These cards are called "white cards" because they are plain and can be customized with printing, logos, or encoded data.

How an RFID White Card Works with the RC522 Module ?

1. The RC522 reader sends an electromagnetic signal to the RFID white card.

2. The card receives power from the signal and transmits its UID (Unique Identifier).

3. The Micro:bit reads and processes the UID.

4. The UID can be displayed on an LCD I2C display, used for authentication, or stored for further use.

Connecting Micro:bit board with RFID-RC522 module and LCD I2C Screen

1- Connecting FRID-RC522 to Micro:bit

2- Connecting LCD I2C screen to Micro:bit

Makecode code to Read RFID Card and Display on LCD

1- Open MakeCode (makecode.microbit.org).

2- Click on Extensions.

3- In the search bar, type "I2C LCD," and you should find an extension for the I2C LCD display. Add it to your project.

4- In the search bar, type "RC522," and you should find an extension for the RFID RC522 module (for reading RFID cards). Add it to your project.

Here's a MakeCode (Microsoft MakeCode) program for reading an RFID card using an RFID-RC522 module with a Micro:bit and displaying the UID on an I2C LCD display.

Here’s how to write the program using MakeCode blocks:

1- Initialize the LCD and RFID module on start.

2- Check for an RFID card presence.

3- Read the UID of the card.

4- Display the UID on the LCD.