Tony Hawk's Pro Skater cheats and cheat codes for Dreamcast

Cheat codes:

Hold L at the Pause Screen and press the following button combinations:
All stats up to 10: Press X, Y, Up, Down
All Stats up to 13: Press A, X, X, Y, Up, Down
Level Select: Press Y, Right, Up, X, Y, Left, Up, X, Y
Maximum Special: Press A, Y, B, Down, Up, Right
Random Start Locations: Hold L at the Pause Menu and hit: X, B, A, Up, Down
Slow Motion: Press B, Right, Up, Down, B, Right, Up, X, Y 
Turbo mode: Press (X, Left, Up, X, Left) twice.
Unlock Everything: Press B, Right, Up, Down, B, Right, Up, X, Y 

Big head mode:
Press A, B, Up, Left, A, B, Up, Left. 
or
Press X, B, Up, Left(2).

Slow-motion mode:
Press B, Right, Up, Down, B, Right, Up, X, Y.
or
Press X, Left, Up, X, Left.

Unlock Officer Dick:
Get a total of 30 tapes with any character.

Unlock Bails Video:
Get 3 Medals with any character in the competitions.

Unlock Neversoft Bails Video:
Get 3 Medals while playing as Officer Dick.

Private Carrera:
While playing as Officer Dick, Pause the gameplay, after 
hold L and press Y, Up, Y, Up, B, Up, Left, Y.