GAME GENIE CODES: John Madden Football '91.
 No.  Code  Effect
   1  RH9A-R6V2  MASTER CODE--MUST BE ENTERED

Codes 2 thru 5 may cause delays in plays and kick-offs.
   2  B8KA-AADG  Random time on play clock
   3  D4KA-AADG  Random time on play clock

With codes 4 and 5, the computer will run down the play clock - best to use in 2-Player mode.
   4  HWKA-AADG  Play clock starts at 60 seconds
   5  MLKA-AADG  Play clock starts at 90 seconds

Codes 6 thru 11 replace the 5-minute-per-quarter option in the options screen.
It will still display the 5-minute quarter even though a code has been used to change this.
The 15-minute quarter option works as normal.
   6  D2XT-CADL  Each quarter lasts 30 seconds
   7  HTXT-CADL  Each quarter lasts 1 minute
   8  SAXT-CADL  Each quarter lasts 2 minutes
   9  MAXT-CEDL  Each quarter lasts 10 minutes
 10  NAXT-CJDL  Each quarter lasts 18:20
 11  BAXT-CRDL  Each quarter lasts 30 minutes
 12  AB4A-AAGE  Home team starts with 0 timeouts
 13  AF4A-AAGE  Home team starts with 1 timeout
 14  AK4A-AAGE  Home team starts with 2 timeouts
 15  AZ4A-AAGE  Home team starts with 5 timeouts
 16  BF4A-AAGE  Home team starts with 9 timeouts
 17  AB4A-AAGL  Visiting team starts with 0 timeouts
 18  AF4A-AAGL  Visiting team starts with 1 timeout
 19  AK4A-AAGL  Visiting team starts with 2 timeouts
 20  AZ4A-AAGL  Visiting team starts with 5 timeouts
 21  BF4A-AAGL  Visiting team starts with 9 timeouts
 22  RF5A-A618  Infinite timeouts for both teams

With Codes 23 thru 27, if the computer is allowed more than 4 downs, it still punts on the 4th down
so the advantage is yours.
If the computer is allowed less than 4 downs, it will always run plays and never punt.
 23  ALHA-AAB2  Only get 1 play to get a first down
 24  ARHA-AAB2  Only get 2 plays to get a first down
 25  AWHA-AAB2  Only get 3 plays to get a first down
 26  A4HA-AAB2  Have 5 plays to get a first down
 27  A8HA-AAB2  Have 6 plays to get a first down
 28  ALHA-AA3W  Always first down - the down never counts down.
 29  FCJA-AAFJ  Only need 5 yards for a first down
 30  SCJA-AAFJ  Must get 15 yards for a first down
 31  YCJA-AAFJ  Must get 20 yards for a first down
 32  8CJA-AAFJ  Must get 30 yards for a first down
 33  ALJA-AA7R  Always goal-to-go--must get touchdown
 34  ALHT-AA9E  Touchdown worth 0 points
 35  GCHT-BE1E  Touchdown worth 1 point
 36  GCHT-BJ1E  Touchdown worth 2 points
 37  GCHT-BN1E  Touchdown worth 3 points
 38  GCHT-BT1E  Touchdown worth 4 points
 39  GCHT-BY1E  Touchdown worth 5 points
 40  GCHT-B61E  Touchdown worth 7 points
 41  GCHT-BA1E  Touchdown worth 8 points
 42  ACHT-BE5J  Extra point worth 0 points
 43  ALHT-BE5J  Extra point worth 2 points
 44  ARHT-BE5J  Extra point worth 3 points
 45  AWHT-BE5J  Extra point worth 4 points
 46  A0HT-BE5J  Extra point worth 5 points
 47  A4HT-BE5J  Extra point worth 6 points
 48  A8HT-BE5J  Extra point worth 7 points
 49  BCHT-BE5J  Extra point worth 8 points
 50  ACHT-BE46  Field goal worth 0 points
 51  AGHT-BE46  Field goal worth 1 point
 52  ALHT-BE46  Field goal worth 2 points
 53  AWHT-BE46  Field goal worth 4 points
 54  A0HT-BE46  Field goal worth 5 points
 55  A4HT-BE46  Field goal worth 6 points
 56  A8HT-BE46  Field goal worth 7 points
 57  BCHT-BE46  Field goal worth 8 points
 58  BLJA-AA4E  Safety worth 0 points
 59  GCJA-BEWE  Safety worth 1 point
 60  GCJA-BNWE  Safety worth 3 points
 61  GCJA-BTWE  Safety worth 4 points
 62  GCJA-BYWE  Safety worth 5 points
 63  GCJA-B2WE  Safety worth 6 points
 64  GCJA-B6WE  Safety worth 7 points
 65  GCJA-BAWE  Safety worth 8 points

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