routine chrout inputs a trashes a @ 65490 routine main trashes a, x, y, z, n, c, v { ld a, 0 if z { ld a, 89 call chrout } else { ld a, 78 call chrout } ld a, 1 if z { ld a, 89 call chrout } else { ld a, 78 call chrout } }