Sonic Jam: Genesis or Saturn Code?

Then he's full of shit—Sonic Jam's programs were ported over from the original source, not emulated. Genesis code can not natively run on the Saturn, even with heavy modification. It needs to be totally rewritten.

 

Are you sure? The Saturn does have a 68k CPU in it, so maybe it IS possible that they reused at least parts of the code?

 

According to Wikipedia, the Saturn contained a 68EC000, and was used primarily as a sound co-processor. It's a stripped down version of the standard 68k, so I'd imagine the code would not work in its entirety if simply copied and pasted over. Not only that, but then another processor would have to be dedicated to sound since the sound processor is being occupied.

I just think it makes far more sense that it was ported over. Nothing at all seems to imply otherwise, anyway...

 

Whatever, I think it was a fact the source code was ported. In fact, probably only the software engine was ported, as hardware-wise it's completely different. For instance, in Sonic 2, the 128x128 tiles are drawn directly instead of 16x16 chunks.

 

Hmm, were the easy and normal modes for each game stored in their own independent files? (I mean, besides the music and sound effects)

If so, it could be interesting to see if their structure is any similar to the old ROMs, and which changes were made for them.

 

I think once Lost ported the level layout or something back to the S1 ROM from the S1 in Sonic Jam...

 

I've heard something to that effect, but never actually seen the result. I'd be pretty interested to see it, honestly.

Also, Saturn disassemblies, huh? Maybe we could hack NiGHTS or something :P

 

Most of the data are stored in separate files, and the majority of them are in the exact same format as in the Genesis version. Some of the most relevant -

Folders-
/Sonic12 - Sonic 1 and Sonic 2 game files
/Sonic3K - Sonic 3 and Sonic 3 and Knuckles game files

Suffixes-
_E - Easy Mode
_N - Normal Mode
"Original mode" (no changes from the Genesis) has no name suffix

Extensions-
SN1 - Sonic 1
SN2 - Sonic 2
SK2 - Sonic 2 and Knuckles
SN3 - Sonic 3
SN4 - Sonic and Knuckles (Sonic 3 and Knuckles)

Filenames-
ACTTBL - Level Sprite object layout (all levels)
RINGACT - Level Ring layout (all levels)

Program-side, there would only be difficulty-level test before loading the data files, and a couple of other places, such as setting the boss hit counter during the object's init. There would really be no level of difficulty in back-porting the difficulty-level changes

 

Sonic 1 Easy mode

 

I find it weird that Sega did a decent job on Jam but have done a half a***ed job ever since Sonic Mega Collection.

BTW with regards to using the 68k, it depends on how it is wired up and even if the used it, which chip would handle the sound since it controlled the SCSP?

(http://en.wikipedia.org/wiki/Saturn_Custom_Sound_Processor)

 

You can run your own code on that 68K in Saturn, usually the code you run on it is a sound engine, but nobody forbids you to use that CPU for other tasks... I have no idea how much access that 68K has to the rest of the system... I'll be doing Saturn dev in the next year then I'll find out how things go...