.define scrollx $d25a
.define scrolly $d25d
push af
push hl
  in a,($dd) ; get P2 inputs
  ld hl,(scrollx)
  bit 0,a
  jr nz,+
  dec hl
+:bit 1,a
  jr nz,+
  inc hl
+:ld (scrollx),hl
  in a,($dc) ; get P1+2 inputs
  ld hl,(scrolly)
  bit 7,a
  jr nz,+
  inc hl
+:bit 6,a
  jr nz,+
  dec hl
+:ld (scrolly),hl
pop hl
pop af
jp $0073