SCHG How-to:Convert the Hivebrain 2005 disassembly to ASM68K

From Sonic Retro

(Guide was originally written by Puto)

This guide covers converting your split disassembly from SNASM68K (the assembler) to a better, faster assembler known as ASM68K.

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

With this:

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 replaced this incorrect line in SkipSecurity:

		move	a6,usp	  ; set usp to $0

With the proper:

		move.l	a6,usp	  ; set usp to $0

Which results in a perfectly assembling 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.

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.

That's it! Enjoy a faster build of your hack.