Level Select
     At  the  Level  Selection  screen,  press  C-Up, C-Right, C-Down,
C-Left, R, L, Z, C-Up, C-Right, C-Down, C-Left. If done correctly, you
will hear a sound.

All Weapons
     At  the  Level  Selection  screen, press C-Left, C-Down, C-Right,
C-Up,  Z,  L, R, C-Left, C-Down, C-Right, C-Up. If done correctly, you
will hear a sound.