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saturn emulator on xbox?

thailees - May 9, 2004

		thailees		May 9, 2004
			hello, i want to know theres no such thing as saturn emulator for xbox right? i heard that emulator cant be on xbox cuz saturn games are high quality?

		ExCyber		May 9, 2004
			Hasn't happened yet to my knowledge, and I don't particularly expect it to happen, simply because the Xbox scene will probably die before Saturn emulators are advanced enough to let it happen.

		Alexvrb		May 10, 2004
			Ex, do you think they'll ever become fast enough to run full speed (with sound and reasonable compatibility) on an Xbox anyway?

		Pearl Jammzz		May 10, 2004
			Doubtful, unless sumone who can code like a mofo. PSX doesn't even run all games at full speed. Same w/ N64.

ExCyber

May 10, 2004

	
	
		
		
			Ex, do you think they'll ever become fast enough to run full speed (with sound and reasonable compatibility) on an Xbox anyway?

I think it could happen, not assuming that it will. Hardware advances might make it a moot point with emu authors. Still, when I look at the current state of MAME's psikyosh driver (being 100% portable code and to my knowledge using no hardware acceleration) I have a very difficult time believing that we will all need 4GHz PCs to achieve reasonable Saturn emulation.

Buffi

May 10, 2004

	
	
		
		
			Originally posted by Pearl Jammzz@May 10, 2004 @ 12:09 AM



 Doubtful, unless sumone who can code like a mofo. PSX doesn't even run all games at full speed. Same w/ N64.

Well... since the psx is a faster system then saturn it should be easier to emu saturn right?

		RitualOfTheTrout		May 10, 2004
			No thats not exactly how it works. The saturn has several different chips that all need to run in sync, and getting this behavior emulated has proven to be quite difficult. Althogh there seems to have been alot of progress latley. Just check the Saturin WIP thread at the top.

ExCyber

May 10, 2004

	
	
		
		
			Well... since the psx is a faster system then saturn it should be easier to emu saturn right?

Emulation *difficulty* is determined by the complexity of a system, not its speed.

PSX has one CPU running at 33MHz (the GTE is a coprocessor, not a full processor - it basically adds instructions to the CPU similar to MMX or 3DNow)

Saturn has two CPUs running at 28MHz, a sound CPU running at ~11MHz, and a general-purpose DSP running at ~14MHz. It also has a dedicated multilayer playfield generator supporting tile-based rendering, scaling/rotation, and row/column scroll, operations that the designers of DirectX Graphics and OpenGL certainly did not have in mind.

	
	
		
		
			The saturn has several different chips that all need to run in sync, and getting this behavior emulated has proven to be quite difficult.

Although it's certainly not trivial, I think that the severity of this problem tends to be overstated (maybe we can get a word from Runik on this? My SH-2 interpreter doesn't run yet :sigh ). I do know for sure that Saturn is not like Atari 2600 or Vectrex where losing a couple clock cycles will mangle the display...

Runik

May 10, 2004

	
	
		
		
			Originally posted by ExCyber@May 10, 2004 @ 07:32 PM



 Although it's certainly not trivial, I think that the severity of this problem tends to be overstated (maybe we can get a word from Runik on this? My SH-2 interpreter doesn't run yet :sigh ). I do know for sure that Saturn is not like Atari 2600 or Vectrex where losing a couple clock cycles will mangle the display...

Accuracy isn't that important : the fact to delay some interruptions for exemple doesn't prevent the machine to run.

But this is only for the SH2.

The other chips need to be fed with an accurate number of cycles.

The SMPC for instance needs to have the exact timing for each command issued, otherwise it'll go off sync with the interrupt masking of the SCU, resulting in its interruption never being triggered and an endless loop ...