Here are some cheats and tips for the game Pitfall: The Mayan Adventure.
Atari 2600 version:
Press Down, A(26), Down at the title
screen.
All weapons:
Press A, B, Up, C, A, C,
A at the title screen.
Nine lives:
Press Right, A, Down, B, Right,
A, B, Up, Down at the title screen.
Extra lives and weapons:
Press Left, A, Down, B, Right,
A, B, Up, Down, A, B,
Up, C, A, C, A at the title
screen.
Unlimited continues:
Press C(4), Left, A, Down, Up,
Down at the title screen.
Level select:
Press B, Right, A, Down, Right,
Up, B, Left, A, Up, Right,
A at the title screen, then press Up or Down
to select a starting level.
Speed mode:
Press B, A, Right, C, Right,
Up, Down at the title screen.
Lever sequence practice:
Press B, A, Down, C, Right,
A, B at the title screen.
View credits:
Press C, Right, Down, C, Right,
Down, C, Right, Down at the title
screen.