Gunstar Heros disassembly?

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RetroGames
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Re: Gunstar Heros disassembly?

Post by RetroGames » Thu Mar 03, 2016 4:48 am

MintyTheCat wrote:...GNU GAS has very good documentation going back all the way to the late 1980s and good support too.
Interesting. Seems that GNU GAS's executable is also known as "AS", apparently a legacy from Unix. Wonder why the author of this "Macro Assembler AS" I linked to decided to also use the name "AS"... Anyway, sorry if I confused things. To reiterate: I was not talking about GNU GAS, aka "AS", I was talking about "The Macro Assembler AS", aka "AS".

...I'll see myself out... 8)

Sik
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Re: Gunstar Heros disassembly?

Post by Sik » Thu Mar 03, 2016 7:19 am

AS is a rather generic name for whatever is the system's assembler.
Sik is pronounced as "seek", not as "sick".

MintyTheCat
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Re: Gunstar Heros disassembly?

Post by MintyTheCat » Thu Mar 03, 2016 11:46 am

Yes, you often find that many things are a carry over from Unix and indeed C and Unix are so closely tied you simply end up knowing about both as you learn the other.

But yes, it is rather unfortunate that they use the name "AS" all the time :) In the Amiga days we used to just say DevPac or SEKA (not the pornstar :D).
Very few people had a C compiler back then as they were expensive so most people used something like Assemby or some form of BASIC like Amos.
I actually got my first C Compiler back in 1996 and that was actually under DOS on the PC.
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r57shell
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Re: Gunstar Heros disassembly?

Post by r57shell » Tue Mar 08, 2016 2:06 pm

r57shell wrote:I just wanna warn you.
If you wanna make full disassembly of some game, it will took for you several years. (solo)
Natsumi wrote:I'd say months is closer to accurate, depending on the size of the ROM and complexity of the code. Of course, the skills of the user also factors on the speed they can resolve code. Yes it could take years, no doubt, but I know people who can make a building disassembly of a game in even weeks. Not very well documented but fully usable.
This:
OrangyTang wrote:It's nice to have some actual documentation on the assembler now. :) And after basically marking the whole rom other than the header as data I finally have an export from IDA that reassembles into what looks like a byte-identical rom. Which is a start.
Even though it's buildable, it will take time, to make all offsets working. (pointers)
And, during month, you don't go far beyond simply buildable assembly that. BTW, you can define whole ROM as data, it will be buildable, but it won't help a lot.
Just for info: this took for me several weeks.
Next comming version... I spent few more weeks.
I'm not doing full disassembly, because I think it's useless, and does not worth the time, to make small change.
Whole dissassembly makes sense only if you want to change WHOLE game, or large part of it.
Image

MintyTheCat
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Re: Gunstar Heros disassembly?

Post by MintyTheCat » Tue Mar 08, 2016 7:22 pm

Yes, that is true, R57Shell, but also people learn a great deal by examining commercial ROMs.

I tend to apply patches using a program that I wrote to keep things clean and easily reproducible.
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