You have to load all those variables you defined into a, then from there into b, c, d, e... > ld b, (BoxLeft) > ld c, (BoxUpper) > ld d, (BoxRight) > ld e, (BoxUpper) > call _Iline Should be... ld a,(BoxLeft) ld b,a ld a,(BoxUpper) ld c,a ld a,(BoxRight) ld d,a ld a,(BoxUpper) ld e,a call _Iline Pain in the ass, right?...That's ASM for you. James.