Dwedit's Board

patters

Member

Registered: 2008-03-03

Posts: 12

SMS speedhacks for specific games

Hi all,

Long time no see (last logged in back in 2008!). Were Dwedit's SMS speedhacks saved from obscurity?
https://web.archive.org/web/20060508092 … php?t=2922

Or were they built into SMSAdvance?

Thanks,

Patters

Dwedit

Administrator

From: Chicago

Registered: 2004-12-12

Posts: 1,017

Website

Re: SMS speedhacks for specific games

Second link still works, https://www.dwedit.org/dwedit_board/vie … php?id=170

I do still have "smsspeedhack" on my PC.... let me do something about it.

It's a disassembler that picks out suspected self loops, need to be good with ASM (or an emulator's debugger) to tell whether it's likely used or not.

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"We are merely sprites that dance at the beck and call of our button pressing overlord."

Dwedit

Administrator

From: Chicago

Registered: 2004-12-12

Posts: 1,017

Website

Re: SMS speedhacks for specific games

Doesn't do much to keep it sitting on my computer

This is unsupported, I don't even know what it does anymore.  Go yell at 2006 me if it's confusing.  Like why is the code for regular Z80 named with a "gb_" prefix...

Anyway, it outputs a bunch of possible places that look like back branches that poll something.  You'd use this with a Game Gear/SMS Debugger with breakpoints (like Emukon) to confirm that those are indeed places to look at.  Then hex-edit in your own patch.

Also found the "sms_speedhacks.zip" file...

Anyway...
"smsspeedhack_source.zip" is source code made for Visual Studio 6.0.
"smsspeedhack.zip" is a console tool that outputs possible backwards branches, for ASM programmers. Use this with a debugger and hex editing your own code in there.
"sms_speedhacks.zip" is a few IPS patches that speed up some games when run on emulators, adding in HALTs.  (for the games: Phantasy Star SMS, Shining Force 2 GG, Shining Force 3 GG, Sonic 1 GG)

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Attachments:
smsspeedhack_source.zip, Size: 38,891 bytes, Downloads: 20
smsspeedhack.zip, Size: 97,089 bytes, Downloads: 23
sms_speedhacks.zip, Size: 646 bytes, Downloads: 22

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"We are merely sprites that dance at the beck and call of our button pressing overlord."

patters

Member

Registered: 2008-03-03

Posts: 12

Re: SMS speedhacks for specific games

Thanks, that's great. I'm updating/writing some Python3 builder scripts for many of the GBA emulators. Many of them have reserved space in the compilation rom headers for CPU branch hacks (opcode, length which are mostly unsupported) but curiously SMSAdvance has a single bit toggle for "Enable CPU speed hack" but nothing more specific than that.

Can you recall, based on your having forked SMSAdvance (for the GBAMP IIRC), whether this actually does anything? I mean, should I default that bit to 1?

EDIT. Ah - I see in the official builder it's actually greyed out :)

Last edited by patters (2022-04-06 5:32:03 pm)

patters

Member

Registered: 2008-03-03

Posts: 12

Re: SMS speedhacks for specific games

The Game Gear Sonic speedhack you attached must be a bad IPS. The data payload already exists in this verified good dump:
https://datomatic.no-intro.org/index.ph … =25&n=0349

If I apply it to the (Rev 1) ROM it breaks.

Last edited by patters (2022-04-06 5:33:00 pm)