White: King a1; Queen b1; Bishop c1; Knight d1; Rook e1; Pawn a2, b2, c2, d2, e2.
Black: King a5; Queen b5; Bishop c5; Knight d5; Rook e5; Pawn a4, b4, c4, d4, e4.
There is no castling; pawns cannot make an initial double step.
Very simple, very quick, and the calculator actually played a reasonable game (after I modified it a bit!)