Press I, Select, II, wait for the player selection triangle to appear, press Down, Up, Down, II and press Run.
Infinite MP
Press Down 4 times, wait for the player selection triangle to appear, press Up, Left, Down, hold Right and press Run.
Level Select
Press I, II, wait for the player selection triangle to appear, press II, II, I and press Run.
Sample Play Menu
Press Up, Up, Down, Down, I, II, Run.
Sound Test
Press Up, Up, Down, Down, Left, Right, Left, Right, II, I, Run
Turbo fire