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Genesis Development

Jeffrey - Jan 28, 2003

		Jeffrey		Jan 28, 2003
			I see a lot of development for the Genesis in the form of Demos and simple games. They are always in ROM format as to run on an emulator for the GEN. However, it seems to make more sense to me that programmers would choose the Sega CD format. CD drives are fairly common among Gen players. Many emulators now support the CD along with the GEN alone. And the format is easier to transfer from emulator to actual hardware making it more versitle. I would love to put together timely compilations of new development for the system on a CD. SO why do Genesis developers not make use of the CD? Is it harder to program? Is it really much different from the Genesis alone? Finally, are there any developement pages for the Sega CD. It is easy to find GEN demos and games but not so for the CD.

		antime		Jan 28, 2003
			It's always more difficult to make your program run from CD than from ROM, as in the latter case you don't have to deal with the CD controller, filesystems etc, though for small programs that fit into RAM it might not make much of a difference. It is true that if you intend to run your code on real hardware burning a CD is easy, and you can burn quite a lot of them before the cost adds up to a programmable cartridge, but from a development point of view the cart format is much easier. As for hardware info, the emulator authors should have the information you need. I've also seen some documents being posted on the message board at Eidolon's Inn... where many of the emulator authors also post.

		AntiPasta		Jan 28, 2003
			And the 32x? To me it seems like a cool machine to dev on, but I have yet to see any techdocs...

		antime		Jan 28, 2003
			There's supposedly a CD with 32X info floating around. Eidolon should have more info on it.

		Alexvrb		Jan 28, 2003
			Shoot, if you're gonna code for the 32X, why not make a 32X CD game? That is, a game that utilizes the Sega CD + 32X hardware, running off a CD. That'd give you more RAM, sound, power, etc. But of course you'd have to be mad skilledz.

		Jeffrey		Jan 28, 2003
			I see Dreamcast demos and games! Where are the Sega CD homebrews? All the Sega CD development stuff seems to focus on copying games, not creating them. Has anyone burned a new game or demo? I know you cant play a gen rom on sega cd, but can you transfer a code from one platform to another with translation? even a simple demo?

		Pearl Jammzz		Feb 1, 2003
			Well....couldn't you take say all the sonic games on Genesis, convert the code so it will run on SCD then make a front end thing to select which game you wanna play? Is it that hard to transfer codes from a genny game to a SCD one?

		antime		Feb 1, 2003
			When running from cartridge, you can directly access all content of the cartridge. When running from CD, you can only access what you can fit into RAM, which is 64 kB in the Megadrive plus 768 kB (of which 500 kB is accessible by the CPU) in the MegaCD. Modifying a game to run from CD is somewhere between insanely difficult and impossible, depending on the game. There's a reason the Genesis forum says what it says on the front page. I'm sure Arakon can tell you more if you PM him and ask nicely..

		Carnivol		Feb 1, 2003
			The reason why there's not many SegaCD homebrews are most likely that the possibilites for testing things easy in a emu hasn't been available until now, also, the DC, PSX and many other system has link-up capabilities (so you can direct transfer things to your unit) Also, the SegaCD needs both SegaCD and Genesis knowledge! (As the data both must be used by the SegaCD hardware and the Genesis hardware) So you're basicly making something for 2 consoles... As for 32X too... Well... with the possibilites to run code for that is almost none... that's why we haven't seen much of that yet... Also, while we're at it... What's the COM port on the first Mega-drive/Genesis model for?

		Alexvrb		Feb 2, 2003
			Actually there was a decent amount of straight ports from cart to CD, they slap some CDA in there and call it a release... but that is a port and not a ROM-loading deal, where the existing code expects to work like a cart and not have loading points like CD games.

antime

Feb 2, 2003

	
	
		
		
			Originally posted by Carnivol@Feb. 02 2003, 1:55 am



What's the COM port on the first Mega-drive/Genesis model for?

There was a modem released in Japan that used the port. From the Megadrive's point of view, it's a third controller port.

		AntiPasta		Feb 2, 2003
			well, we can run 32x roms on emulators can't we? By the way it is very common in the Master System homebrew scene to rip open a cart and replace the ROM with a socket + flashrom. I'd love to try some devving on the 32x if I could just get that darn cd :-(

		Carnivol		Feb 3, 2003
			antime: thanks (I couldn´t find any documentation on it...) Anyway, is there any way it can be used for sending data to the unit? (I got a backup unit, but I´m just curious about that port...) I think if there´s some way you could make it receive test data by that port... we´ve got something like the PSX + AR + Caettla = yay Why was it removed from the later releases of the console? (atleast in America and Europe)

antime

Feb 3, 2003

	
	
		
		
			Originally posted by Carnivol@Feb. 03 2003, 9:51 am



Anyway, is there any way it can be used for sending data to the unit?

Sure, but you need a way to get the receiving software to run on the Megadrive first, and if you can do that you can run all your code the same way. And if you really want a cable connection, you can just as easily use any of the other controller ports. As I said, hardware-wise they're identical.

	
	
		
		
			Why was it removed from the later releases of the console?

Dunno, maybe they scrapped the idea of introducing the modem service elsewhere and removed the port as a cost-saving measure.

		AntiPasta		Feb 3, 2003
			well, about this Caetla type of idea, it wouldn't work. Why? Because your code has to be run from RAM then, not from the cartridge. With the PSX this is no problem (it always runs from RAM because of the CD) but the Genesis has only 64k... which is a bit paltry. The SCD/MCD/32x, on the other hand, has an additional 512k so that would suffice.

antime

Feb 3, 2003

	
	
		
		
			Originally posted by AntiPasta@Feb. 03 2003, 11:46 pm



the Genesis has only 64k... which is a bit paltry.

Kids of today..

TakaIsSilly

Feb 3, 2003

	
	
		
		
			Originally posted by antime+Feb. 03 2003, 4:11 pm-->QUOTE(antime @ Feb. 03 2003, 4:11 pm)