Proper use of disassemblers?

[TheCount]

I dunno what I'm doing wrong, but I never seem to use disassemblers the right way. It's been a long time since I tried, but what I remember is that if I try to disassemble something and use an assembler (I use CDoty's ASM and DISASM) to piece it back together I get unrecognized mnemonic errors all over the command line output Could anyone enlighten me?

[Lazy Bastard]

Which disassembler, which assembler, and what kind of program (elf, exe, 32-bit, 16-bit, etc)?

[TheCount]

The programs I'm trying to use are called asm.exe and disasm.exe. I think the author is Charles Doty. They are meant to use with 68000.

[Lazy Bastard]

Are you modifying a macro of some kind? Occasionally, when an illegal index register name is passed to a macro, you'll receive an "Unrecognized Mnemonic" error when the macro is expanded.

Hmm...I think Doty only made the 68000 assembler set JAS/LD/Maccer...on that note, if you don't have Maccer, I recommend you get it, as it corrects some issues with JAS, and adds some functionality.

Also, a good disassembler for 68000 is the PC port of IRA (Intelligent ReAssembler).

If you like, I can dig up my copy of the JAS/LD/Maccer "suite", as well as the last version of IRA.

On that note, if you can get your hands on a copy of IDA (Pro Advanced, if at all possible), there's a good plugin for it for Genesis/Master Drive ROMs, which I also happen to have a copy of. I suppose I should just add these to the Downloads section.

[Lazy Bastard]

Hmm...it would appear Michael Hope made Maccer, incidentally.

[Chemist]

TheCount, for what do you need a disassembler?

[Lazy Bastard]

I've added the tools I mentoned to the Downloads section.

[MIR]

Isn't the 680xx series a processor made by moterola used in the early Macintosh computers before the AIM (Apple, IBM, Motorola) partnership that brought us the PowerPC processor (known as the G1)? are you disassembling a Macintosh?

[Lazy Bastard]

The 68000 series was used in a wide variety of computers, including Macs, as well as the Sega Genesis/Megadrive, NeoGeo (console version), and a bunch of arcade systems. It's still used today in some applications, and in any case is a good model to study.

[MIR]

That is right and a Sub processor of the G1/2 was used in the N64 (ie project Dolphin as well).

Another one is the TI Z processor. It is used in some of the early handheld consoles and is the proccesor of chose in graphing calculators.

[Dualscreenman]

Project Dolphin was the Gamecube.

[MIR]

>_< Thats is why i mentioned Also Project Dolphin which used a Solely Ibm PPC processor. Dear god have you seen the circutry specs for the processor. (*u*) Ibm had it avalible on their micro processor portion of their website. It was an amazine read!

[MIR]

For those of us who get off on what Wired Magazine calls "Infoporn", here is IBM's PPC webpage.

http://www-306.ibm.com/chips/products/powerpc/

[TheCount]

Thanks to all. I got IRA, disassembled the ROM I wanted disassembled, and I'm yet to see if I can assemble it back. I'm trying to ASM hack a megadrive ROM btw. The only problem I'm having now is having to wait about 10 minutes for Notepad2 to open a file several megas long. Over a million lines of text. Whoope. Does anyone know of a text editor that can open it quickly? XVI32 opens that sort of lengthy files quickly, but it seems awkward to work on a disassembly with a hex editor.

[Lazy Bastard]

Win32Pad and PSPad are my favorites. TextMorph is also occasionally useful for some impressive features. Anyway, Win32Pad is simplest, PSPad has the most options, but either should do fine.