Thunder Force II.

 No.  Code  Effect
   1  AEET-AAAA  Start with 2 lives
   2  A2ET-AAAA  Start with 7 lives
   3  BEET-AAAA  Start with 10 lives
   4  CTET-AAAA  Start with 21 lives
   5  GJET-AAAA  Start with 51 lives
   6  MJET-AAAA  Start with 91 lives
Get infinite lives with Codes 7 or 8 but don't combine them
   7  ATSA-AA2T  Infinite lives--top-view missions only
   8  ATKT-AA4Y    Infinite lives--side-view missions only  
   9  AEET-AAFJ  Start with 1 credit
 10  ATET-AAFJ  Start with 4 credits
 11  BEET-AAFJ  Start with 9 credits
 12  DEET-AAFJ  Start with 25 credits
 13  GJET-AAFJ  Start with 50 credits
 14  MJET-AAFJ  Start with 90 credits
 15  ATEA-AA20  Infinite credits