Open Source Firmware for Electronic Shelf Labels
OpenEPaperLink is an alternative protocol and firmware implementation for electronic shelf labels. Multiple Displays are supported with ESP32-based access points and 802.15.4 radio communication.
⚠️ This project is provided solely for non-commercial use under the CC BY-NC-SA 4.0 license.
Technical Features
Power Consumption
9µA current draw with 40-second latency. Power usage reduces automatically when no AP is detected.
RF Protocol
Block-based transfers with selective packet acknowledgment. 4096-byte blocks with checksum verification.
Data Storage
Local EEPROM storage for display data. MD5-based block verification before writing to prevent corruption.
Transfer Speed
~5kB/s data transfer rate under normal RF conditions, using 42 packets per 4K block.
Network Protocol
Tag check-in every 40+ seconds. AP maintains pending transfer queue with MAC-based addressing.
Hardware Setup
ESP32-based access point with 802.15.4 radio tag. Supports multiple tag models using ZBS243/M2 chipset.
Home Assistant Integration
Monitor and control your electronic shelf labels through Home Assistant.
View IntegrationDevice Integration
Tags and access points appear as Home Assistant devices with sensor data and controls.
Display Controls
Create custom display content with text, shapes, icons, QR codes, and sensor data visualizations.
AP Configuration
Configure Bluetooth, channels, sleep duration, and Wi-Fi parameters through Home Assistant.
Sensor Data
Monitor temperature, battery, signal strength, and more for each device.