Level select:
Press Left, Left, I, Right, Right, II, Up, Down, Up, Down.
The music will change to confirm correct code entry.
Press Up or Down to change the level number displayed in
the bottom left corner of the screen. Press Run to begin
game play at the selected level.
Level skip:
Plug in a NEC Avenue 6 pad in six button mode into port
one to automatically complete the current level.