To Get Cheat Mode
Pause the game and press Left + A, B, X, A*2, B, X, A, Start. An information screen will appear allowing invincibility, level select, pausing without a dim screen(wow), or viewing the entirelevel. Note: Using this code may prevent completion ofthe game.
Eight plasma shots
Pause the game and press A*2, B + L, A*2, X,B + L, X.
Another cheat code
Pause the game and press Y, A, B*2, A, Y, A,B*2, A.
Full Ammo
Pause the game and press A, B, B + L, B, X,A, X*2.
Extra Life
Pause game play and press B + X, B*3, A*2,X, A.
Extra Continue
Pause the game and press A, B, A, B, X, Y,X, Y.
The Princess
Pause the game and press Left + A, X*2, X + B, X,A, X, Left + A.
See the Map
Pause the game and press A, X, A, X, A*4.
Fill Up Life Bar
Pause the game and press A + X, B, A, B*2, X + Y,B, A.
Level Skip
When you enter a level press start so the game pauses. After you do that do the following code as fast as you can a, b, x, a, a + x, b + x, b + x, a + x. Once you do this you will see Jim and the title to the next level. You can do this as many times as you like on any level.