A standalone Web Bluetooth tool for writing text and images to nRF5x e-paper displays. No app required 鈥?open the HTML file in your browser and connect.
- Text mode: Type messages with configurable font, size, alignment, and color (black/red)
- Image mode: Upload images with Floyd-Steinberg / Atkinson dithering
- Three-color support: Black/White/Red displays (and B/W only mode)
- Configurable display size: Works with 4.2", 2.9", 7.5" and other resolutions
- Fully offline: Single HTML file, no server or internet required
- Cross-platform: Android (Chrome), macOS/Windows (Chrome/Edge), iOS (Bluefy browser)
- Flash your e-paper display with EPD-nRF5 firmware
- Open
eink-ble-writer.htmlin a Web Bluetooth-capable browser - Click Connect and select your display
- Type your message or upload an image
- Click Send to Display
Any electronic shelf label (ESL) running EPD-nRF5 firmware with:
| MCU | Common Source |
|---|---|
| nRF52811 | Hema / Alibaba ESL |
| nRF52810 | Sifei ESL |
| nRF51822 | Laowu 4.2" B/W |
| nRF51802 | Laowu 4.2" B/W/Red |
Display drivers: SSD16xx, UC81xx series (black/white and three-color).
| Item | Value |
|---|---|
| Service UUID | 62750001-d828-918d-fb46-b6c11c675aec |
| Characteristic UUID | 62750002-d828-918d-fb46-b6c11c675aec |
| CMD_INIT | 0x01 |
| CMD_WRITE_IMAGE | 0x30 |
| CMD_REFRESH | 0x05 |
See PROTOCOL.md for full protocol documentation.
Safari does not support Web Bluetooth. iOS users need Bluefy (free).
For remote updates (e.g., push messages from your computer to a display at home), see server.py 鈥?a minimal FastAPI backend that the frontend can poll for new content.
This project is a Web Bluetooth client for the excellent EPD-nRF5 firmware by @tsl0922, which is licensed under GPL-3.0. The firmware handles all e-paper display driving and BLE communication.
This client (the HTML/JS code in this repository) is an independent work that communicates with EPD-nRF5 firmware over Bluetooth Low Energy, and is released under the GPL-3.0 License.
GPL-3.0 License. See LICENSE for details.