My Hackage quest!

Well, I might not be very useful here, but I can answer your most important questions. Technically, a Genesis ROM can't be greather than 4 MB, if I remember correctly. Sonic & Knuckles is already 2 MB, and so is Sonic 3. Well, I'm unsure about this - perhaps someone will confirm - but isn't Gens capable of "supporting" 8 MB ROMs ?

 

This would be near impossible. The closest thing that could be done is a Sonic Collection type thing. A single ROM that contains Sonic 1, 2, 2&K, 3&K, spinball, and bean machine. This could be done like those "6 in 1" type carts. You could have to decompile each game into a source code, then recompile it so the pointers and crap would all match different offsets.

I am not sure about this, but I know that emulators can handly at least 6 MB.

 

Genesis has different limitations than the Sega CD.

 

S1 = 512 KB/0.5 MB

S2 = 1 MB

S3&K = 4 MB

Total = 5.5 MB

Size-wise, it looks like it'd work, but hacking-wise, that would be incredibly difficult. I'm not going to say "impossible," though, because 1) it's good to look on the bright side (sometimes) and 2) it may be possible down the road. The question is whether or not someone would go through all that work.

 

S3&K is full of duplicated crap (eg music, have you ever noticed how all the s&k music is also in the s3 rom?). So if someone was to completely decompile the ROM and put it back together again with all the duplicates removed and pointers changed etc etc, it would probably lose at least a megabyte.

Then you have the fact that the S&K rom also has S2 objects in S3&K format (so that you can play Knuckles in S2). These are totally useless in the S3&K rom. Aside from the obvious palette problems (which was, apparantly, Sonic Team's excuse for not letting you play Knuckles in S1), the S1 objects would also have to be in S3&K format to be able to do that. So, convert the S2 and S1 objects into S3&K format, and then remove the S1 and S2 engines, remove the S2 objects from the S&K rom, convert the S1 levels to use 128s instead of 256s, put them all together and change the S3&K engine to let you play levels in S1 and S2 in the right order, and then you're done. By that time, you should have a ROM of under 4MB.

That is a lot of work, I know, and I don't think it is worth doing. But it would certainly have interesting results.

 

Not exactly.The real S&K cart have a external 256k chip that contains that s2k code,and is only called when you use sonic 2 with S&K.In roms,S&K or S3K don't contain that 256k chip,only the (working) S2k rom at the end (because the chip was dumped too to make it work).

 

It would be near impossible for one of the greatest tech members here.

First off, this would require more than hex, since there is a LOT of porting involved. You would have to modify most graphic and music engines to be compatible with s3k. If you somehow manage to do that, there would be the porting (which can be a pain in the arse). Between all that you would run into a number of errors, since 68K (which would be needed) is quite a lot to take in and remember. You would have to miss some stuff out, because the 68K can only handle up to 8 mb of data at a time in the registers. You would have to change the instructions between games, you would have to create instructions to change the fact that (for example) Sonic 1 has ended and you would need to make an instruction for it to go to the begining of Sonic 2.

Out of all this, I have only scratched the surface. And I'm still learning, so if I have made a mistake in here (which I probably have) then please correct me.

EDIT:

Yes, but if you're only using Hex then you are limated to combining S&K with any other Gennesis Sonic game. If you were to combine Sonic 1 and Sonic 2, you would need the knowlage of 68k.

Again, please correct me if I am wrong.

 

I'm confused, so correct me if I'm wrong, Taruko. Do you intend to simply 'glue' S1 through to S&K together into one big ROM, so that when you complete (for example) Sonic 1, it moves directly on to Sonic 2, save from a slideshow sequence? Or is this something completely different?

Also,

I don't understand.

Probably not relevant, but with the idea for slideshows between levels/games, I thought that couldn't happen in S2 without starting the whole ending sequence. Although I'm not sure about that.

 

Like everyone here, I think it would be possible, but a hell of a lot of work.

You could:

Add Sonic 2 onto the end of S3&K, changing pointers to the obviously now different offsets, as well as make modifications to the game engine. Then you could edit the S3k level playlist to begin with Emerald Hill, the Chemical Plant ect.

Once the player reaches the end of Death Egg, you could have the ending play (don't let Sonic jump off the plane though), but change the pointer telling it to play the credits to point to Angel Island.

I'm sure we could sacrifice Sonic 2's music and replace it with Sonic 3's.

However I'm not sure how you would get Sonic 1 on the front of that.

 

No. ROMs cannot be bigger than 4MB.

 

Possible, but I doubt many people could do that, exept Sega, ofcourse.

That instruction would be one in 68K, not hex. The slideshow would be hand made, so that would take a while to make the pallet, art, choose which compression, import it, etc.

Again, the command would be a 68K instruction. What is this "crap lourde of editing" you speak of?

This would be an impressive hack, but most people know the story anyway.

Yes. Since SA2B would look shit on a Gennesis.

 

A Jonathan Whiteford productions presents:
Not Another Long Post!

Ok, so seriously.

Read my last two posts in this topic. I would be repeating myself if I said what I should.

It would have to be at a maximum of 16 colours, and it would have to be compressed with the same compression algorithm as the art in Sonic whicheverthfuckyou'reusing.

Good idea. Only the "SEGA!" sound replacement would have to be in .wav format, 4 seconds long and at (I have totaly forgot) rate.

Have you noticed that the music in the game doesn't sound like instruments? That's because the Z80 can't handle it. The music you put in it has to be in .MIDI format, and can be imported via SonicQX (by Saxman).

It would require you to remake the sprites for Sonic whicheverthefuckyouplanonusingforthis. You may need to use 68k ASM (I'll explain that in a second.) to make the behaviours of these objects too.

The Motorola 68000 is the CPU of the Gennesis / MegaDrive. It's the root of all evil code. I'm hoping you would now understand why this would be extremely difficult for you to do all this now that you know what the 68K is. (ASM is the Assembaly code of the 68k.)

Again, correct me if I am wrong.

 

MP3 <-> WAV convertor. Easiest thing you mentioned.

Putting the songs from SCD Jap. into a Genesis game wouldn't work, because, with the exception of the Past songs, all of the SCD songs are digital audio. The only way you could put them into the game would be to try and replicate the songs in a similar way that a MIDI sequencer would, and even then, you wouldn't get a close match, because there's stuff in those songs that you can't do with the Genesis' sound chip.

A "conversion thing" (I think you mean a porter) for those two items does not exist, at present. You might be able to port them to another game, but that would be really complicated and probably very difficult.

The Motorola 68000 (68K = 68000; get it?) is the Genesis' processor, and it's also the assembly language used by said processor.

Ah, crap. Looks like Soil beat me to it.

 

Yey :D