What Do the Purple Lights Mean
When a square lights up purple it can mean one of three things:
- This is the location of the active piece. Meaning this is the piece you just lifted or are currently touching. This helps you find the home of the piece if you lift it but decide not to move it.
- Purple can also mean that a piece is placed on a square where the board expects there to be no piece. So if you illegally move a piece the square you moved it to might light up purple.
- A purple square can also mean that the ChessUp thinks a piece is missing. If the ChessUp expects there to be a piece on a square but doesn't sense a piece it will light the square purple. The only exception to this is at startup when all the start squares are colored blue (for white) and green (for black) and when loading a game position (using a FEN string)