export const USI_BLACK_PIECES = ['P', 'L', 'N', 'S', 'G', 'K', 'R', 'B'];
export const USI_WHITE_PIECES = ['p', 'l', 'n', 's', 'g', 'k', 'r', 'b'];

export const USI_BLACK_TEAM = 'black';
export const USI_WHITE_TEAM = 'white';

export const USI_PAWN_BLACK_TYPE = 'P';
export const USI_PAWN_BLACK_PROMOTE_TYPE = 'P+';
export const USI_PAWN_WHITE_TYPE = 'p';
export const USI_PAWN_WHITE_PROMOTE_TYPE = 'p+';

export const USI_LANCE_BLACK_TYPE = 'L';
export const USI_LANCE_BLACK_PROMOTE_TYPE = 'L+';
export const USI_LANCE_WHITE_TYPE = 'l';
export const USI_LANCE_WHITE_PROMOTE_TYPE = 'l+';

export const USI_KNIGHT_BLACK_TYPE = 'N';
export const USI_KNIGHT_BLACK_PROMOTE_TYPE = 'N+';
export const USI_KNIGHT_WHITE_TYPE = 'n';
export const USI_KNIGHT_WHITE_PROMOTE_TYPE = 'n+';

export const USI_SILVER_BLACK_TYPE = 'S';
export const USI_SILVER_BLACK_PROMOTE_TYPE = 'S+';
export const USI_SILVER_WHITE_TYPE = 's';
export const USI_SILVER_WHITE_PROMOTE_TYPE = 's+';

export const USI_GOLD_BLACK_TYPE = 'G';
export const USI_GOLD_WHITE_TYPE = 'g';

export const USI_ROOK_BLACK_TYPE = 'R';
export const USI_ROOK_BLACK_PROMOTE_TYPE = 'R+';
export const USI_ROOK_WHITE_TYPE = 'r';
export const USI_ROOK_WHITE_PROMOTE_TYPE = 'r+';

export const USI_BISHOP_BLACK_TYPE = 'B';
export const USI_BISHOP_BLACK_PROMOTE_TYPE = 'B+';
export const USI_BISHOP_WHITE_TYPE = 'b';
export const USI_BISHOP_WHITE_PROMOTE_TYPE = 'b+';

export const USI_KING_BLACK_TYPE = 'K';
export const USI_KING_WHITE_TYPE = 'k';

@@ -217,24 +217,59 @@
 = 'white';%0A%0A
+export const USI_NULL_TYPE = '*';%0A%0A
 export const

Add Constant of nullPiece.