Knuckles Chaotix 32x assembly hack

[Tony H]

If you read my recent post in the "VG School of Hacking" forum (here at GSHI), then you know about the new emulator (Gens 9.5b) that lets you search SH2 memory (Sega 32x). 32x games use regular Genesis "FF" type RAM, and they also use special SH2 memory. I've spent many hours playing around with this new emulator and using the SH2 memory addresses that I found in the Gens 2.11 32x debugger.

I adopted Chemist's method of using save states and tracing through lines of code in the 68000 debugger and got it to work with the 32x debugger. I finally have a working 32x assembly hack for Knuckles Chaotix 32x.

I've been able to make a lot of Game Genie codes for Knuckles Chaotix 32x, but I could never make any GG codes for the special stages. The main reason was because none of the RAM addresses used in the special stages were in the FF0000 to FFFFFF range. The special stages use SH2 memory instead.

Anyways, the bad news is that as of now, Game Genie codes that modify areas of the ROM that are specifically for the 32x won't work in Gens. The good news is that you CAN hack the codes into the 32x ROM...


Knuckles Chaotix 32x (5/NTSC version only, will not work on A/PAL version)

This hack will make it so that you don't lose any rings because of
time in special stages (you normally lose 1 ring about every second).
Don't let your ring count go over 255 or else you may "time out".


Open up your Knuckles Chaotix ROM (5/NTSC version) with a hex editor
(your ROM must be in "bin" format). Hack the following codes into
your ROM...


32x Master Code
$07CC:6002


Don't lose rings (from time) in special stages
$07D31C:7000


===================================

The "7000" in the second code is a 32x instruction. You can modify it so your ring count goes up or down with time.

7000 = add #00, r0

7001 = add #01, r0

7002 = add #02, r0

70FF = add #FF, r0 (this would subtract 1)

70FE = add #FE, r0 (this would subtract 2)

Be warned that if your ring count goes above 255 while in a special stage, you will "time out".


Hopefully, Gens will someday support Game Genie codes in the 32x areas of the ROM.

If anyone wants to know how to do this, Ugetab made a post awhile back that explained Chemist's method of using the Gens 68000 debugger. With a few alterations, it will work with the 32x debugger.

[Lazy Bastard]

Interesting...I shall have to dig ugetab's post up as well.

[King Of Chaos]

I wonder, does Kega Fusion support any if these codes that Gens doesn't?

[Tony H]

It's been awhile, but if I remember correctly, Kega Fusion didn't support any 32x Game Genie codes at all (not even the ones that Gens supports). One of these days I'll get the newest version of Fusion and check it out.

[Tony H]

Shadow Squadron / Stellar Assualt 32x

Open up your Shadow Squadron 32x ROM with a hex editor (must be in
"bin" format). Hack the following codes into the ROM...


$07CC:6002
32x Master Code


$116572:0009
Blasts from the large ship guns won't hurt you. Works on either
"Feather 1" or "Feather 2".


$10D1A2:0009
The "Feather 1" ship won't use up any fuel when you use the special
weapon (special weapon is activated by double tapping the "A" button
and holding it on the second tap). Doesn't work on "Feather 2" ship.


EDIT: 0009 = NOP

[Viper187]

That's interesting, Tony. Can we do that stuff with SegaCD games as well? It's been forever since I really looked at any of this stuff. hehe

[Tony H]

As far as I know, it will work on SegaCD.