68000 CPU simulator

About BasiliskII, a 68k Mac emulator for Windows, MacOSX, and Linux that can run System 7.x through MacOS 8.1.

Moderators: Cat_7, Ronald P. Regensburg

Post Reply
User avatar
rickyzhang
Mac Mechanic
Posts: 193
Joined: Mon Sep 15, 2014 7:59 pm

68000 CPU simulator

Post by rickyzhang »

I'm enhancing Basilisk II to run System 6. One task I struggled with is to read Macintosh SE 24 bit ROM to figure out how to override the compressed dispatch table directly before it get expanded by the ROM.

I found the logic that expands the compressed dispatch table. But my progress is SLOW. I wonder if anyone can recommend me a 68000 CPU simulator to run a snippet of 68K binary or assembly at will.

I want to debug it by executing the code rather than read and look up the assembly.
There is an App for that!
https://github.com/rickyzhang82
User avatar
adespoton
Forum All-Star
Posts: 3075
Joined: Fri Nov 27, 2009 5:11 am
Location: Emaculation.com
Contact:

Re: 68000 CPU simulator

Post by adespoton »

Can you do it by running MACSBUG in Mini vMac or BII and just injecting and stepping through the code?
User avatar
rickyzhang
Mac Mechanic
Posts: 193
Joined: Mon Sep 15, 2014 7:59 pm

Re: 68000 CPU simulator

Post by rickyzhang »

I found Easy68k as an assembler and a simulator. But it is painful to type the assembly from ROM file and replicate the data in the code.

What version of MacBugs I should use for System 6?
There is an App for that!
https://github.com/rickyzhang82
User avatar
adespoton
Forum All-Star
Posts: 3075
Joined: Fri Nov 27, 2009 5:11 am
Location: Emaculation.com
Contact:

Re: 68000 CPU simulator

Post by adespoton »

I'd try either 6.2.x or 6.3.x -- these are the ones that were released during the System 6 timeframe or shortly afterwards. That said, I remember using 6.6.x on 68k Mac OS 7.6, and I'm pretty sure it worked on 7.1 as well, so you could try a more recent build and see if it works. An alternative would be TMON.

The nice thing about MACSBug is that it's scriptable, so you can write a quick loader to load your assembly and test it, and even dump the results to file.
Post Reply