Got the Shotgun figured out so that it does automatic burst fire. Pretty fun.
Terminator 2: Judgment Day (Genesis/MD)
AX5A-BA60 +
AM5A-AA62 +
DAGA-CA68
Allows you to always have a special modified version of the Shotgun (B button) with infinite ammo, even at the very beginning of the game. The Shotgun is modified so that if you hold down the B button, the Shotgun will automatically shoot bursts of 4 rounds instead of a single shot.
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Here is the other code for the second M-16 if you felt like experimenting. I may dig deeper into it and see if I can find out why they have separate programing for the two. The Mini-gun only has a single number used in the programing. Here are the ID numbers used in the programing: 01 = Mini-gun, 02 = M-16, 03 = M-16, 04 = Shotgun.
AS5A-BA60 +
AM5A-AA62 +
DAGA-CA68
The first code (AS5A-BA60) is the only one that's different from the first M-16 code above.
EDIT: Here's the code from the first M-16...
AM5A-BA60 +
AM5A-AA62 +
DAGA-CA68
Always have the M-16 machine gun (B button) with infinite ammo, even at the very beginning of the game.
EDIT2: After some testing, this is what I found out.
Looks like the Pistol, both M-16s, and the Mini-gun all do 1 point of damage. I'm assuming that the difference is that the M-16's and Mini-gun have a much higher rate of fire, which causes much more damage. I can't find any difference in the two M-16s.
Made another new code while I was digging around:
AJ6A-CA20
1 shot kills enemies.
Don't know if there are any bosses in this game so don't know if it works on them, but tested it on an enemy in level 6 and seemed to work fine.