Convert the Hivebrain 2005 disassembly to ASM68K
From Sonic Retro
Revision as of 20:19, 17 October 2021 by Brainulator (removing broken code)
(Original guide by Puto)
This guide covers converting your split disassembly from SNASM68K (the assembler) to a better, faster assembler known as ASM68K. This tutorial is also necesary if you want to work on a 64-bit OS without restarting on a new split.
The only thing that SNASM68K has that ASM68K doesn't seem to support, is the "align" directive, as well as negative cnops. The align issue can be fixed with a simple macro that can be placed above StartOfRom:
align macro cnop 0,\1 endm
Next edit the line below in build.bat:
snasm68k.exe -emax 0 -p -o ae- s1comb.asm, s1built.bin
asm68k /o op+ /o os+ /o ow+ /o oz+ /o oaq+ /o osq+ /o omq+ /p /o ae- s1comb.asm, s1built.bin
And then in the source file itself replace this incorrect line in "SkipSecurity:":
move a6,usp ; set usp to $0
with the proper:
move.l a6,usp ; set usp to $0
to result in a perfectly assembled ROM, which assembles so quickly I can barely have time to see the window open.
Better yet, since this supports long filenames, I can then replace the include.exe directives (in the format of ; include=xxx) with proper "include" directives, which allows me to completely skip the creation of s1comb.asm! This is very useful, because it means when you get a compiling error, you'll no longer have to check the line in s1comb.asm, and then track the location to sonic1.asm.
In the source file, replace all instances of:
with the proper:
Ensure that you replace all instances of:
As such, this entire line becomes unneeded in build.bat:
include.exe sonic1.asm s1comb.asm
And the ASM68K line can be changed to assemble sonic1.asm directly.
Now, delete this files:
- s1comb.asm (if it exists)
That's it! Enjoy a faster build of your hack.