The Chessnut Air is a smart chess board with 64 RFID scanners. Each piece has an RFID chip that the board uses to identify the piece. Each square has a LED which can be on or off. It can connect to a PC/SmartPhone using BluetoothLE. It doesn't use an engine and only sends the current position and receives back which leds to turn on/off, all the chess logic is in the app it connects to by bluetooth. Led data can most of the times be translated to a UCI move except for piece promotion. Usually only 2 leds light up indicating the move from-to squares. But it's also possible for multiple leds to light up for example: when castling or when multiple pieces need to be moved (happens if the position sent by the board is not corrent. During normal gameplay this should not happen as castling is the only legal move that moves 2 pieces at once) I have no idea which squares a castling or en passant move will light up but with some testing, those leds patterns can
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