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NES emulation

vbt - Feb 2, 2003

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ExCyber

Apr 5, 2004

	
	
		
		
			sound was not poor infact the sound was good no skipping nothing

Did you support the DMC for the NES games? If so how did you handle synchronizing the DMA timing with the CPU emulation?

darkdaemon

Apr 5, 2004

	
	
		
		
			Did you support the DMC for the NES games?

No I didn't like I said before I loaded the nes sound data into the saturn 68K and that's all I had to do with the sound. I think this is a not for sure ideal yet but for better sound too we could rip the nes sound from the rom reencode it to Saturn sound data and load it to the Saturn's 68K for better speeds. Now it time for me to get outte here.

		mal		Apr 5, 2004
			Pardon me for sounding a little incredulous but... Got source? Or at least binaries?

Runik

Apr 6, 2004

	
	
		
		
			Originally posted by darkdaemon@Apr 5, 2004 @ 04:21 AM



 See you got all of the graphics of the nes rom loaded onto one of the SH-2's not much memory used leaving some for speed!!

:huh

AFAIK there's no distinction between master and slave memory ... the only processor-specific memory are the I/O registers ...

Maybe I misunderstood something ?

		AntiPasta		Apr 6, 2004
			well it's possible to configure part of the SH2's cache to be 'private' memory... but I think that's only 2K.

		ExCyber		Apr 6, 2004
			IIRC there are both 2K (split between cache and private memory) and 4K (exclusively private memory) modes. The latter is probably useless unless you're putting both code and data into it (otherwise you'd eat up your performance gain with uncached instruction fetches).

		antime		Apr 6, 2004
			Are you sure you can configure it for 4K RAM? The 7604 manual only mentions the 4K 4-way cache and 2K 2-way cache + 2K RAM configurations. You can disable the cache, but doesn't that just mean you always bypass it?

darkdaemon

Apr 6, 2004

Mal

	
	
		
		
			Pardon me for sounding a little incredulous but...

I'll release Snes Zelda sometime this month ISO format. ExCyber

	
	
		
		
			The latter is probably useless unless you're putting both code and data into it

good eye for things that I've used. Code and data both. Runik

	
	
		
		
			AFAIK there's no distinction between master and slave memory ... the only processor-specific memory are the I/O registers ...

The Saturn is equipped with 16 megabits (2 megabytes) of main RAM. 12 megabits of video RAM. And 512K of audio RAM. ExCyber

	
	
		
		
			IIRC there are both 2K (split between cache and private memory) and 4K (exclusively private memory) modes. The latter is probably useless unless you're putting both code and data into it (otherwise you'd eat up your performance gain with uncached instruction fetches).

Each SH2 comes with an internal 4K RAM cache in order to speed up processing tasks. Well now I'm outta here. Keep your eyes here sometime this month I'll release the Snes Zelda Emulator. Peace

Runik

Apr 7, 2004

	
	
		
		
			Originally posted by darkdaemon@Apr 7, 2004 @ 12:07 AM



 Runik 




    	
	
		
		
			AFAIK there's no distinction between master and slave memory ... the only processor-specific memory are the I/O registers ...
		
		
	

 The Saturn is equipped with 16 megabits (2 megabytes) of main RAM. 12 megabits of video RAM. And 512K of audio RAM.

:lol:

Thanks for giving me infos that I'm aware from a long time

As Antime stated, according to the 7604 doc you can only have 2KB of private RAM ...

Mask of Destiny

Apr 7, 2004

	
	
		
		
			Originally posted by antime@Apr 6, 2004 @ 10:27 PM



 Are you sure you can configure it for 4K RAM? The 7604 manual only mentions the 4K 4-way cache and 2K 2-way cache + 2K RAM configurations. You can disable the cache, but doesn't that just mean you always bypass it?

The cache is always mapped into the SH-2s memory space. It would just be very unwise to use it as RAM when the processor is trying to use it as cache. Disabling the cache entirely allows you to safely use all 4KB of cache RAM for other purposes.

antime

Apr 7, 2004

Yeah, just found the relevant bit in the doc (p.224):

	
	
		
		
			When the cache is disabled, the area H'C0000000 to H'C0000FFF can be used as 4 kbytes



of on-chip RAM.

		ExCyber		Apr 7, 2004
			Anyway, I just looked at it and the PPU has several times more RAM than will fit in the cache. It could still be interesting to try running some inner loops in cache, but the idea of putting a whole PPU emulation inside won't work.

dhau

Apr 7, 2004

	
	
		
		
			Originally posted by DBOY@Feb 2, 2003 @ 05:17 PM



 I dunno. It wasn't doable on PSX last I checked. One emulator managed to run games but it ran them at about 1/2 notmal speed.

PSX has a fantastic NES emulator: it's called It Might Be Nes (IMBNes)

Here is the link to IMBNes site...

		rbn		May 8, 2004
			im interested

vbt

May 8, 2004

	
	
		
		
			Originally posted by darkdaemon@Apr 7, 2004 @ 01:07 AM



 I'll release Snes Zelda sometime this month ISO format.

Any news ?

		slinga		May 8, 2004
			sigh VBT he was one of those lamers (not the Slinga kind of lamer though, those kind don't release stuff because they can't get stuff to work).

		vbt		Dec 19, 2006
			One of my good old topic, I think I will release the sources as I didn't work on it for a long time, I prefer the SMS

		vbt		Jan 29, 2007
			Try this one it's still as slow as first release I guess. I'm just playing a little with the sources, it's just a bad port. I have still in mind to put the sources online but it's not ready to compile. Here are the small changes since last binary : - compiled using elf gcc 4.xx - added fps counter - removed some mappers

		vbt		Feb 24, 2007
			The sources, there is nothing special inside as it's a simple port.

		RockinB		Feb 28, 2007
			I've tried sl_ballonfight on real Saturn. It works fine, but doesn't accept any control pad input.

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