Saturday, October 13, 2012

More about the tool

Thanks to Alex and Matt I finally managed to get a proper dump using MAME.

I just run MAME and all the PCs will be dumped to a file. It has some nice efficient tricks as when it notices that it's inside a loop it simplifies the output and only dumps the loop once, so I thought the file should be quite small.

When it's dumping the PC, the thing runs damm slow and it takes 5 minutes to start playing, but the best of all is that the dump file in those 5 minutes is quite small and only takes 24Gigs of data :)))

I created a new tiny tool that reads all those PCs and puts them in a table (the famous decrypting table). So we are ready to see if using MAME will make this game finally work on another set.

I create a new JOJOBA CD to tried it on MAME, I update with the new CD and....didn't work!

For some reason it starts executing code from other addresses which didn't do before, so I started adding one by one those special locations. The process is quite tedious, as you must
A) Update game in MAME
B) Run it and see if it works
C) If it doesn't work, look for the code that isn't updated in the table
D) Update table
E) Create new CD
F) Go to A)

Good news is that apparently SF3-2I only executes code from 06000000 to 06100000. In the worst case and unless I come up with a better idea, there is always the option of analysing the whole 1Mb of code and data in Assembler BY  HAND and create the table in this way. That can take me like a month, so I'll keep as plan B or C or X ;)).

More coming soon.

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