quicky quide to Game Genie codes for game gear mastersystem

[Hybrid]

i posted this over at segaage.com just decided to bring it here

ok first thing we want to do is find a raw code with kega fusion (the cheat searcher for kega fusion is very limited and is best if used for known values ) you will need another program called Game genie converter which is available here http://gshi.org/downloads/ggconv.zip
the game we will be using in this example is Machine Gun Joe

this is your game genie/PAR window you can open this window to from File > Game Genie/PAR
or press ATL+G


from here click the code finder to come up with the code finder set up


count is an exact value
Difference is how far higher or lower
Percent is an approximation counter presumptively used for power bars (100% 75% 50% 25%)
State is off/on

were going to be dealing with count here is the count window



simple as pie enter the value of what you are looking for and it shows various possibilities
lets try lives with this game
so type in 2 in the value box die then one and one more time with 0
from here we got two possibilities left time to test the codes

going from the main code window and enter the first code like this 00c134:04
hmm didn't work next try the other code 00c142:04 aha! it worked
now that we have an address time to move over to meka
first thing we want to do is open the file mekaw.cfg with notepad look for this section

-----< DEBUGGING FUNCTIONNALITIES -------------------------------------------
debug_mode = 0
(set to 1 to permanently enable debug mode. you can also enable
it for a single session by starting MEKA with the /DEBUG parameter)
debugger_console_lines = 24
debugger_disassembly_lines = 15
debugger_disassembly_display_labels = 1
debugger_log = 1
memory_editor_lines = 16
memory_editor_columns = 16
(preferably make columns a multiple of 8)

change debug_mode from 0 to 1
now time to open up meka

go under debug and click enabled if not checked already
the degger should stop a few times press c then enter to continue
wait until you get into the game and leave no text in text line to stop game play
then type
b w C124 and enter to set a breakpoint press c to continue it should snap as you loose a life


now type memedit press enter and it will bring up a memeditor editor

click ROM and type 0ACD and press enter
in the goto box change the 35 to 1A or 00 press c lose a life

1A loads the value instead of decreasing it
00 No ops it

now die testing the code out a few times now time to open up Game Genie code converter
click the GG/GB button make sure that Game Gear is selected on the right and
now in the hex code box is listed as this
address is the first box second box is ? compare third box is : value
so once filled out the code should look like this




0ACD ?35 : 00 (or 1a)

there you have infinite lives

1AA-CDF-3BE
or
00A-CDF-3BE

[Hybrid]

we covered how to find raw codes with fusion now we will be digging into various things that can be done with the raw codes here are the codes that we will be using
c276: lives
c275: energy
c245: world
c26D: power
now just like before start up meka and load the rom but when the bios screen loads and breaks
set a write break point on the world
type b w C245 then c a few times til the title screen comes up then start the game.




wow looks like from here we can set all the starting data here from world to stage to power
lives even starting energy
now back to the world code
now look at these two lines

3401: 3E 01 LD A, 01h
3403: 32 45 c2 LD (c245),A

which means load a value of 1 to to c245

so changing which world you start at is simple
now its not at 3401 but 3402
so the starting code for starting world address is
3402 ?01:??

after a bit of testing i found out that there are 6 worlds

so any value between 1 and 6 will work
setting every thing else works the same

now lets remove the breakpoint 0 with
b remove 0

now lets start with lives as mention prior starting lives can be set except they have a decimal
value. lets go to infinite lives set a write break point at c276
and die and it breaks



now theres two ways to deal with this right here the addresses we are interested in are
4395: D6 01 SUB 01h
changing the 01 to 00 will give you infinite lives
or
4398:32 76 c2 LD (C726h),A
changing the 32 3A which instead of subtracting the value of that address it will subtract but load the value. so nothing changes
there are some other things which get reset after you die
energy gets set back to 3
power get set back to 0
so that means that the other codes for start with energy and power are incomplete
so set those values to which ever you use energy has a max of 5 and power can be anything
now onto infinite energy removing the other break point and adding a write to the energy get hit
and it snaps to


now once again there's two ways to deal with it
no op the DEC 139C by setting it to 00
or change the write at 13A0 from 32 to 3A

so to recap the codes we made tonight for this game

start at world use 1-6
3402?01:0? 0?4-02C-E6E
start with max energy
3411?03:05 054-11C-E66
43A7?03:05 053-A7B-E66
start with ?? power
3416?00:?? ??4-16C-E6A
43AB?00:?? ??3-ABB-E6A
infinite Lives
4396?01:00 003-96B-E6E
or
4398?32:3a 3A3-98B-2A2
Infinite energy
139c?3D:00 003-9CE-19E
or
13A0?32:3A 3A3-A0E-2A2

[Mezmorize]

Nice there Hybrid, I'll have to check out Meka's debugger sometime.

[orcanaoftime]

Thanks for posting the how to! Excellent!

[Lazy Bastard]

Nice; gotta add this to the Library for sure