To view a CRC test easter egg, hold Up + Left + A + B on Player 2's controller and press Reset.
Invincible
Turn on the game and Reset the game 77 times. Then while playing, pause the game and press Up, Up, Down, Down, Left, Right, Left, Right, B, A and Start. If done right, you'll be invincible.
Re-Energize
When low on energy, press Start to pause the game, then press Up, Up, Down, Down, Left, Right, Left, Right, B and A. Then press Start to unpause the game, and your energy meter will be filled. You can do this once per game.
Round Select
Turn on the game and Reset the game 25 times. Then at the title screen press Up, Up, Down, Down, Left, Right, Left, Right and Start. If done right, a stage select menu should appear.
Sound Test
While holding Up, A and B, press Reset on the Control Deck. A screen will appear showing the sound selections in the game. Now you can press Up or Down to select a sound and B to hear it.