To get the indicated amount of credits, pause the game and enter the following codes:

• 500 Credits: RIGHT, LEFT, RIGHT, LEFT, L, R, UP, UP, R, R, L, L.
• 1000 Credits: UP, DOWN, UP, DOWN, LEFT, RIGHT, L, R, L, R, R, L.
• 5000 Credits: UP, RIGHT, DOWN, LEFT, L, L, RIGHT, LEFT, R, R, L, L.