To input the following codes, pause the game, then hold down the L1 and R1buttons. you'll then press circle, circle, left, triangle, circle, x. If you've done this correctly, you'll see the words "Enter Cheat" on the screen.

Unlimited Ammo
L2, L1, Square, L2, L1, R1
Full Adrenaline
L1, R2, R1, Up, Triangle, Circle
Player Suicide (This can only be done in single-player mode)
X, Triangle, Circle, Right, Triangle, Circle
Kill Nemesis
Down, L2, L1, R1, Up, Square
Hide HUD
Circle, Down, Circle, Up, Triangle, Circle
Pickup OSS Document
Up, X, R2, R1, Up, Square
Disable Shellshock
L2, R1, L2, L1, Triangle, Triangle