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Old 12-16-2004, 05:55 AM   #4
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Join Date: Oct 2001
Location: Chaoyang, Beijing, China
Posts: 826
Default Re: Genesis Pointers

> Does anyone know where I can find some docs on how to
> calculate Genesis pointers? So far, the info I've found is
> very vauge and it didn't focus on pointers, it just happened
> to mention them.

I've been working on a bunch of Genesis stuff, including repairing/finishing Langrisser II since Hiryuu Honnyaku never got to, Fengshen Yingjiezhuan and The New Prince & the Pauper. So I'll take this question.

They're almost ALWAYS 32-bit big-endian values. The 68000 stores its multi-byte values as big-endian so you don't need to flip things backwards like you do with little-endian families (6502, 65816, Intel stuff).

One thing I noticed is rarely are Genesis pointers under 32-bits in length, so if you try to lookt hem up fromt he location of the text, you almost enver miss. That's something I've been thankfully able to exploit because Genesis compilers tend to scatter pointers across the entire ROM whenever code needs them, instead of having a "pointer table" as you often find in SNES and NES games.

I'm reluctant to make any more broad statements because they might be incorrect for your game. If you can be a bit more specific I'll try to help.

I can provide source code for my Langrisser II script dumper and tools if you want, but not the other two games, which are being done under contract agreement.

P.S. Make VERY VERY SURE your ROM is deinterleaved, or you will not find shit. GROM can deinterleave it, or you can just write your own tool like I did.

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