OpenChess is a smart chessboard, it can show legal moves, plays against you using Stockfish or let you play online games from Chess.com, Lichess, etc. on your physical board.
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- 👣 Step-by-step build guide - covers materials, schematics, assembly, and software setup
- ⚡ Web Flasher - easily flash your ESP32 directly from the browser
Features that differentiate this fork from the original Concept-Bytes project:
- Lichess: Play online Lichess games using the Lichess API directly over WiFi
- Game history: Saves local (not-online) games so they can be reviewed later. If power is lost during gameplay, the game is automatically recovered on reboot.
- Check: Shows a blinking animation on the checked king square and doesn't display or allow illegal moves that would put or leave the king in check
- GameOver: Detects when the game is over and shows an animation with the winner color. Enforces 50-move, 3-fold repetition and insufficient material rules
- Draw/Resign: Buttons in the WebUI can be used to Draw/Resign or Lift both kings off the board and hold them lifted for 2 seconds to end the game in a Draw.
- Castling: Castling is possible by moving the king 2 squares towards the side you want to castle and it will show you where to move the rook.
- En passant: Lift the pawn to show the destination square in red and the captured pawn square in purple
- Promotion: Can be picked from the WebUI or the ChessUp app. If the WebUI or app are not open, a Queen is automatically picked.
- Fixes: Glaring bugs from the Concept-Bytes code that were fixed: Board is rotated correctly (white on the right), Queen and King are on the correct squares and playing infinite moves in a row is no longer possible.
- Calibration: Automatically orders GPIOs, shift-register outputs and LED index mapping. No need to care about pin order or LED strip layout. In simple terms: it can rotate/flip the board. Makes it easier to throubleshoot magnet detection issues by printing verbose info in the serial monitor console.
- Sensors: Added debounce logic. Allows sliding pieces without getting them immediately detected on the first square they briefly touch. Prevents accidental gamemode selection. Optimized sensor column scan (shift-register) for more reliable sensor reads. Added a way to invert shift-register outputs to be used with PNP transistors
- Async: Web server is now Async, website doesn't become unresponsive by moving or not moving a piece. LED animations are now Async and also look cooler
- WiFi: On-demand scan for available networks. Supports up to 3 saved networks, fast auto-reconnect via cached BSSID/channel and AP fallback with captive portal
- Web UI: Allows for easy ESP32 configuration (WiFi credentials, Lichess token, GPIOs, LED brigthness, OTA, etc.), gamemode selection (with AI/Bot config), displays current board state with evaluation and move history, board edits mid-game. Customizable piece theme and square colors, board flip and zoom, move sounds. Easily editable HTML/CSS/JS files which are automatically minified and compressed into LittleFS.
- Brightness: Dark squares now have 70% brightness by default (adjustable in WebUI) this makes them look as bright as light squares (due to contrast)
- OTA Updates: Over-the-air firmware and web assets updates. Checks GitHub releases at boot and automatically updates (configurable). Manual Firmware (.BIN) or Web assets (.TAR) updates via drag & drop in Web UI.
- CI/CD: GitHub Actions workflow automatically builds firmware, LittleFS image, and web assets TAR on tagged releases. Those file are then used by the Web Flasher and OTA updates.
Contributions are welcome! If you have any new ideas to add or feedback to share, I'd love to hear it! Please read the Contributing Guidelines before submitting a PR.
This project is based on Open-Chess by Concept-Bytes, which is licensed under the MIT License.
Original contributions made by joojoooo and all modifications in this repository are licensed under the PolyForm Noncommercial License 1.0.0.
By submitting a pull request to this repository, you agree that your contribution will be licensed under the PolyForm Noncommercial License 1.0.0.
