Project Hub /Security Surveillance & Defense/RFID / NFC Access Systems/Prismo

Intermediate

ESP32

₹500 – ₹1,500

3 – 6 Hours

Partial Kit

Prismo

Prismo is a low-cost, open-source NFC access controller built with an ESP32-C3 and PN532 module for hackerspaces.

Originally published on Hackaday.io

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

ESP32-C3 Development Board with Berg Pins - Unsoldered Rs. 390.00
RFID Reader/Writer RC522 SPI S50 with RFID Card and Tag Rs. 190.00
5V 1 Channel Relay Module Rs. 45.00
10pcs 5mm RED Diffused Light Emitting Diodes - LEDs Set Rs. 39.00
Piezo Buzzer (Big) 6-12V Rs. 45.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

We don't carry yet: Custom PCB / PCB Fab
Enclosure / Box / Case

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How It Works

Prismo functions as a smart, automated access control system by combining wireless identification with microcontroller processing and physical actuation. At the heart of the project is the ESP32-C3 Super Mini microcontroller, which coordinates all system operations. When a user presents an NFC-enabled card or key fob to the PN532 NFC module, the module reads the unique identifier and communicates it to the ESP32-C3. The microcontroller processes this credential data and uses its built-in Wi-Fi capabilities to publish the event over the MQTT protocol to a local Home Assistant server. Home Assistant verifies the credential against authorized user lists. If access is granted, Home Assistant sends a message back via MQTT, instructing the ESP32-C3 to trigger a digital output pin. This output activates a relay, which can complete or break a circuit to unlock a door or enable a machine. Simultaneously, the system provides visual and audible feedback: an RGB LED changes color to indicate success or failure, and a buzzer sounds to signal confirmation. Everything is neatly housed within a custom 3D-printed enclosure, and the entire assembly is powered and connected on a single-layer PCB.

Why Build This

Manage secure access to your hackerspace, makerspace, or club room doors and sensitive workshop equipment using programmable NFC cards.

Integrate physical security directly into a smart home or automation platform like Home Assistant for local event logging and monitoring.

Gain hands-on experience designing and deploying an Internet of Things (IoT) security device using modern microcontrollers and wireless protocols.

Real-World Application

Hackerspace door and tool access control, local event logging, and machine usage safety verification.

Skills You'll Learn

Microcontroller programming

NFC/RFID communication

MQTT protocol implementation

Home Assistant integration

Relay control and switching

PCB assembly

Safety Precautions

Ensure mains wiring controlled via relay is properly isolated and handled according to electrical safety standards.

Technology Tags

ESP32-C3

PN532

NFC

MICROPYTHON

MQTT

HOME ASSISTANT

KICAD

PCB ETCHING

3D PRINTING

IOT

ACCESS CONTROL

Frequently Asked Questions

Do I need an internet connection for Prismo to work?

Prismo relies on a local MQTT broker and Home Assistant server running on your local network. While an internet connection is not strictly required, a stable local Wi-Fi network is necessary for communication between the ESP32-C3 and your server.

Can I use any NFC card with this system?

The PN532 module supports a wide variety of standard NFC and RFID tags, such as MIFARE cards and NTAGs, which can be easily registered within your Home Assistant system as authorized credentials.

How is the relay used to control a door or machine?

The relay acts as an electronically controlled switch. When triggered by the ESP32-C3, it opens or closes an electrical circuit, allowing you to interface with electronic door strikes, solenoids, or machine power switches safely.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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