SegaXtreme

Home	Forums	What's new	Resources

NES emulation

vbt - Feb 2, 2003

< Prev

Next>

		vbt		Mar 16, 2003
			I had a little time to work on that today and managed to display something

		Daniel Eriksson		Mar 16, 2003
			Very nice!

		vbt		Mar 16, 2003
			Does someone have an idea why colors are wrong ?

		TakaIsSilly		Mar 16, 2003
			Looks like wrong pallete data to me. What's the function you're using to convert RGB to the Saturn format?

		vbt		Mar 18, 2003
			Thanks In fact I was always using the NES 64 colors palette, and I have put palette redefinition in comment. Now it work better but it seems on every game the palette is redefined 1 time more than it's needed. SO I loose the right palette.

		vbt		Jul 24, 2003
			Project restarted from zero. This time I will use FCE Ultra as source code and will try to port it correctly. I just started to compile this project and load the ROM in memory

		Tagrineth		Jul 24, 2003
			Just a few side notes: The first Dreamcast NES emulator also ran half speed with sound, but now there are two that run full speed with sound about 99% of the time (I've never seen NesterDC slow down). PS1 isn't a good comparsion. PS1 just doesn't have the CPU muscle of Saturn, and it has half the usable RAM... two 26.8MHz SH-2's clobber PS1's r3000A, then you factor in the ~14MHz 68EC0000 for sound and the 20MHz SH-1... =) I don't know exactly how much the SH-1 could be used, but it could certainly handle the cartridge interface and probably also mapper emulation (incidentally, it has 512kb local RAM, and guess how big NES's biggest games are?).

AntiPasta

Jul 24, 2003

	
	
		
		
			I don't know exactly how much the SH-1 could be used, but it could certainly handle the cartridge interface and probably also mapper emulation (incidentally, it has 512kb local RAM, and guess how big NES's biggest games are?).

I don't think the SH1 can be programmed in any way (or not that we know of) - same thing for accessing the CD buffer

	
	
		
		
			PS1 isn't a good comparsion. PS1 just doesn't have the CPU muscle of Saturn, and it has half the usable RAM

Well, the MIPS is a bit more efficient than the SuperH (at least from my exp) and the hassle involved with running the 2 SH2's in parallel throws away some of the extra performance, even more because they run on the same RAM... so the performance won't be that bigger.

Moreover, what makes you think the Sat has the double amount of RAM?

		Tagrineth		Jul 24, 2003
			PS1 has 2MB total. Saturn has 4.5MB total. Saturn has 2MB general-purpose RAM that the SH-2's can access at will. And that's before you count expansion cartridges.

ExCyber

Jul 24, 2003

	
	
		
		
			PS1 has 2MB total.

No, it has 2MB work RAM. There's also 1MB VRAM and 512KB of sound RAM. The additional RAM in Saturn is dedicated to particular functions (specifically CD block RAM and framebuffers for VDP1-VDP2 rendering integration), so it's not as simple as having 3.5 vs. 4.5.

		Arakon		Jul 24, 2003
			hmm.. that nes emu for psx, called pnes I think, ran mostly fullspeed, and I'm sure it could run fullspeed with some optimizing.. SMS worked too afterall. so full speed on saturn shouldn't be any prob either.

		AntiPasta		Jul 25, 2003
			well PnesX ran slower than imbNES... the first one was written in C and the last one entirely in MIPS assembly. Shows you what a lil' optimizing can do

		vbt		Aug 20, 2003
			It's just to say I've really started to port FCE Ultra, this is a small pic. It seems to be a little faster than previous try of porting FCE 0.1 but it need more work.

		IceDigger		Aug 20, 2003
			Thats amazing vbt. I wish you luck.

		Daniel Eriksson		Aug 20, 2003
			Very nice! What framrate does it run in?

		slinga		Aug 20, 2003
			Hey, seems as if you updated the pic since the morning. Nice work VBT.

		IBarracudaI		Aug 20, 2003
			yes the pic was updated... and what an update!

		vbt		Aug 20, 2003
			a second update with Mario 3 this time. There is no pad management but it should not be too hard. The main problem is the speed, it even slower than SMS emu. Maybe the core of FCE Ultra is slow ? I removed everything useless and won nothing . next tasks are : - pad management - a menu (derived from SMS Emu ) - work on speed (but no idea for now)

		Edge-`		Aug 20, 2003
			Bravo vbt! Please, keep up the good work!

ExCyber

Aug 20, 2003

	
	
		
		
			The main problem is the speed, it even slower than SMS emu.

Do you notice substantial differences in speed between games, or are they all about equally slow?

< Prev

Next>