AllStar Cheat Mode
At the Main Options choose Exhibition then enter R1 R1 R2 R2 L1 L2 L1 L2. If done correctly a fourth option bar for "AllStar" will appear.
During a quarter back or halftime hold L1 L2 R1 R2.
Super AllStar Difficulty Level
At the Options screen highlight Difficulty and press L1 R1 L2.