F0A2-A4DD Play clock is 20 seconds instead of 45
F3A2-A4DD Play clock is 30 seconds

With the next two codes, the computer will run down the play clock--est to use in
2-Player mode. These codes may cause delays in plays and kick-offs

7AA2-A4DD Play clock is 60 seconds
9CA2-A4DD Play clock is 90 seconds

D4A3-6D04 Only have 3 plays to get a first down or TD (down counter starts at 2)
D7A3-6D04 Only have 2 plays to get a first down or TD (down counter starts at 3)
D0A3-6D04 Only have 1 play to get a first down or TD (down counter starts at 4) 
C2AB-64A4 Have infinite plays to get a first down or TD (always 1st down)
3C24-A70D Infinite time-outs
DD69-A407 No time-outs instead of 3--player 1
D169-A407 6 time-outs--player 1 
DB69-A407 9 time-outs--player 1
DD69-A467 No time-outs--player 2
D169-A467 6 time-outs--player 2
DB69-A467 9 time-outs--player 2
82A6-AF64 Safeties worth 1 point instead of 2
82A6-AF64 + 82A6-A404 Safeties worth zero
DDA4-0767 Touchdowns worth 0 points instead of 6
DFA4-0767 Touchdowns worth 1 point
D4A4-0767 Touchdowns worth 2 points
D7A4-0767 Touchdowns worth 3 points
D0A4-0767 Touchdowns worth 4 points
D9A4-0767 Touchdowns worth 5 points 
D5A4-0767 Touchdowns worth 7 points
D6A4-0767 Touchdowns worth 8 points
DBA4-0767 Touchdowns worth 9 points 

3CA7-A707 + 3CA7-A767 Extra points and field goals worth zero
B3A7-A7A7 Extra point or field goal resets score to 0

CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467 + D76C-6D67
Player 2 starts with 3 points
CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467
Player 2 starts with 5 points
CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467 + DB6C-6D67
Player 2 starts with 9 points
CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467 + DA6C-6D67
Player 2 starts with 12 points
CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467 + DE6C-6D67
Player 2 starts with 15 points
CB6C-6D07 + 626C-6FD7 + 486C-6F07 + ED6C-6467 + F06C-6D67
Player 2 starts with 20 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467 + D76C-6D67
Player 1 starts with 3 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467
Player 1 starts with 5 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467 + DB6C-6D67
Player 1 starts with 9 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467 + DA6C-6D67
Player 1 starts with 12 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467 + DE6C-6D67
Player 1 starts with 15 points
CB6C-6D07 + 626C-6FD7 + 416C-6F07 + ED6C-6467 + F06C-6D67
Player 1 starts with 20 points