A Bluetooth-integrated Point-of-Sale (PoS) system using the ESP32 and Cheap Yellow Display.
ESP32 BarcodeShop is a distributed commerce system that bridges the gap between digital inventory and physical displays. It utilizes an ESP32 (Cheap Yellow Display) as a dynamic barcode terminal.
The system allows administrators to broadcast product UUIDs via Bluetooth Low Energy (BLE) to the ESP32, which generates a real-time, scannable barcode. Users can then scan these barcodes using a hardware scanner (like the Eyoyo EY-015P) or a mobile camera to trigger secure transactions via a Flask-based backend.
| Layer | Technologies |
|---|---|
| Hardware | ESP32-2432S028 (Cheap Yellow Display) |
| Firmware | MicroPython, LVGL (Graphics), BLE Stack |
| Backend | Flask (Python), JWT Authentication |
| Scanning | OpenCV (Camera-based), Eyoyo HID (Hardware-based) |
| Communication | Bleak (BLE Client), Requests (HTTP API) |
- Secure Authentication: User registration and login managed via JWT tokens.
- Inventory Management: Admins can dynamically add products to the centralized store.
- Remote Display Control: Admins push product UUIDs to the ESP32 terminal via Bluetooth.
- Dynamic Barcode Generation: The ESP32 renders scannable 1D barcodes (Code 128) on the fly.
- Instant Transactions: Scanning a terminal barcode triggers an automated purchase request to the backend.
Detailed workflow of barcode generation and transaction processing.
- Broadcast: The Admin client uses
Bleakto send a product UUID to the ESP32 via Bluetooth. - Render: The ESP32 processes the UUID and uses an LVGL canvas to render a Code 128 barcode with proper start/stop guard patterns and checksums.
- Capture: A user scans the terminal using an Eyoyo scanner or an OpenCV-powered camera module.
- Execute: The scanner/app sends an authenticated
POSTrequest (including the JWT token) to the Flask server. - Confirm: The server validates the transaction, checks user balance/permissions, and updates the inventory.
Note: This project assumes the user is authenticated. A valid JWT token must be present in the request headers to perform transactions.
- Flash Firmware: Ensure MicroPython with LVGL support is flashed to the ESP32.
- Backend: Run the Flask server and ensure the ESP32/Client can reach the API endpoint over the network.
- Bluetooth: Pair your admin device with the ESP32 "BarcodeShop-Terminal."
Developed by Louai Zaiter (2026)
Created for the Aberystwyth University ESP32 Hackathon.