E-Ink Message Board

Project notes

Board Statement (BS) — ESP32 E-Ink Message Board

Key Technologies: ESP32, SPI, E-Ink, C++, Arduino IDE, Python, HTML/CSS/JavaScript, Embedded Web Server, CAD Design.

Synopsis: Board Statement (BS) is a custom-built, wireless e-ink message board designed to display humorous, tweet-style messages in an office environment. Inspired by the classic Twitter interface, the display features a profile picture, username, date, message content, engagement icons, and a customizable footer.

The motivation behind the project was to create a fun, personalized way to communicate with coworkers while maintaining a practical, low-maintenance desktop display. Since installing additional software or connecting personal devices to the company's network was not an option, the system needed to operate independently while still allowing messages to be updated conveniently. E-ink technology was selected for its low power consumption, excellent readability, and ability to retain an image without continuous power.

The project utilizes a Waveshare 4.2-inch, 400×300 e-ink display controlled by an ESP32 microcontroller. The ESP32 hosts a standalone Wi-Fi access point and web server, allowing messages to be updated directly from a smartphone without an external internet connection or additional software. A custom web interface provides controls for editing messages, updating dates, and customizing the display's footer.

Development began with a Python-based display simulator to design and refine the interface before implementing it in C++ using the Arduino IDE and GxEPD2 library. Custom bitmap graphics, font configurations, and pixel-based text wrapping were incorporated to accommodate the display's limited resolution. After testing and troubleshooting the hardware and firmware, a custom enclosure was designed to house the display and controller, resulting in a compact, self-contained desktop device.