Sounds good, I've added the disassembly to the original post.
Also, I have a question about Rainbow Edition in general. It was always my understanding that these hacks were sold as EPROM upgrade kits for operators with the original board, but something I saw while disassembling this turbo code suggests that there was some kind of hardware protection added by the hackers. The hijacked turbo code leads here before running Rainbow Edition turbo code proper:
Code:
0E544A movem.l D0-D4/A1, -(A7) ; Push registers to stack for later retrieval
0E544E clr.w D2
0E5450 clr.w D0
0E5452 move.b $201201.l, D0 ; Reads 0x40
0E5458 move.b $281201.l, D2 ; Reads 0x02
0E545E sub.b D0, D2
0E5460 subi.b #$30, D2 ; Result: 0x0E
0E5464 jmp ($4,PC,D2.w) ; Jump to $E5478 (Rainbow Edition's turbo code)
The $200000 region isn't normally mapped to anything in CPS1 games. I see this is accounted for in Mame's CPS1 driver, as these addresses are forced to contain the correct values that create the correct jump offset to the turbo code. But what did this actually look like on the board? Was Rainbow Edition exclusively found on bootleg hardware as opposed to an upgrade kit for legit boards?
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Re: Digging into the secrets of SFII: Rainbow Edition
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