Gp2x Emulation Status

[DavidBeoulve]

Neo Geo MVS: Runs at full speed in games that do not use hardware scaling (most of them), that is to say, 60 FPS with sound at high quality (22050hz) with about 299 Mhz ARM920T clock. With 11050hz audio, runs at about full speed at 266 MHz too. Can run at full speed with sound off at 200 MHz as well.

Whoa - Epicenter - you mean that there's that much different from 266MHz to 300MHz? If a GP2X can handle 300MHz than Neo Geo emulation is (very nearly) spot-on with 22khz sound?

 

[xythen]

Whoa - Epicenter - you mean that there's that much different from 266MHz to 300MHz? If a GP2X can handle 300MHz than Neo Geo emulation is (very nearly) spot-on with 22khz sound?

My new MK2 barely runs stable at 233MHz... it starts crashing at 240MHz after about 10 minutes playing.

Guess I'll have to stick to the highly optimised emulators like DrMD and HU6280 for now.

 

[Epicenter]

Neo Geo MVS: Runs at full speed in games that do not use hardware scaling (most of them), that is to say, 60 FPS with sound at high quality (22050hz) with about 299 Mhz ARM920T clock. With 11050hz audio, runs at about full speed at 266 MHz too. Can run at full speed with sound off at 200 MHz as well.

Whoa - Epicenter - you mean that there's that much different from 266MHz to 300MHz? If a GP2X can handle 300MHz than Neo Geo emulation is (very nearly) spot-on with 22khz sound?

Sure. Metal Slug averages 50-60 FPS .. barely noticably below 60 FPS. With automatic frameskip it's not noticable at all. Dropping 68K clock a tiny bit helps too. Dropping Z80 clock a large amount provides a boost as well. I *always* run GNGeo2x at 299 MHz; 266 is intolerable for me now! Remember if you get undesirably low framerates in GNGeo2x drop 68K clock until they rise! This will cause more 'bullet time' smooth slowdown in-game as the emulated CPU tries to keep up with the game; as it gets more stressful it may slow, but the emulator will stay 100% smooth and not choppy like it gets when the *GP2X's* CPU is overworked. This way, it's just a slower EMULATED CPU that is being taxed. The Z80 processor can be underclocked significantly as well but you will see sound slowdown if you take it TOO low in some games (e.g. below -35%) and it is taxed heavily.

 

[Yono]

Yeah, the wiki is where I look for the latest info...literally tons of great info there, but it's only as up to date as people want it to be:

http://wiki.gp2x.org/wiki/Emulation_Speculation

BTW, I just ordered my GP2X yesterday, should arrive next week, before my holidays start!

That page looks a bit old... may somebody update it? Don't want to make an account for that...

At least we should mark vobbo's hu6280...

Updated.

 

[White Demon]

There is also decent ZX Spectrum Emulator the Fuse:
http://www.zen71790.zen.co.uk/

Fuse is an awful emulator. I tried it and could not get anything to work.

Try GP2Xpectrum instead.
http://www.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,5,1225

This ran everything I threw at it flawlessly, and has options to configure the GP2X's buttons to spectrum keys as well (works great for game key configs).

 

[___]

How come it says that PSP is very likely? That seems absolute bull to me... maybe psp demos and homebrew can be ported, but emulated??? and who is talking about similar hardware? AFAIK they couldn`t be more different...

 

[DijiTao]

How come it says that PSP is very likely? That seems absolute bull to me... maybe psp demos and homebrew can be ported, but emulated??? and who is talking about similar hardware? AFAIK they couldn`t be more different...

I think I'll go change that... Takes a look at the history page:

2:33, 3 June 2006 Catron (PSP added)

I don't know what Catron is smoking...

 

[Elephant Gun]

SNES and Genesis are very playable, but with both emulators there are a small selection of games that do not work (ie, do not even load up)

 

[Winterkid]

SNES and Genesis are very playable, but with both emulators there are a small selection of games that do not work (ie, do not even load up)

Those ROMS might use hacks/tricks only the original hardware might be able to use. I still have yet to see any SNES emu with full SuperFX functionality that works well.

 

[DavidBeoulve]

Sure. Metal Slug averages 50-60 FPS .. barely noticably below 60 FPS. With automatic frameskip it's not noticable at all. Dropping 68K clock a tiny bit helps too. Dropping Z80 clock a large amount provides a boost as well. I *always* run GNGeo2x at 299 MHz; 266 is intolerable for me now! Remember if you get undesirably low framerates in GNGeo2x drop 68K clock until they rise! This will cause more 'bullet time' smooth slowdown in-game as the emulated CPU tries to keep up with the game; as it gets more stressful it may slow, but the emulator will stay 100% smooth and not choppy like it gets when the *GP2X's* CPU is overworked. This way, it's just a slower EMULATED CPU that is being taxed. The Z80 processor can be underclocked significantly as well but you will see sound slowdown if you take it TOO low in some games (e.g. below -35%) and it is taxed heavily.

• Run at 300MHz if possible
• Lower the Z80 (sound) and 68K clock speed for smoothness

Good advice even for folks who can't do the first!

I'm starting to yearn for my GP2X.

 

[epitaph]

• Run at 300MHz if possible
• Lower the Z80 (sound) and 68K clock speed for smoothness

Good advice even for folks who can't do the first!

Keyword: "if possible" -- it's usually not possible to run your GP2X at such high speeds. Epicenter just happens to be the lucky owner of one being able to go unusually high. Mine is stable at 290 MHz and runs for a few (10-20s) at 295 MHz before crashing (this is an MK1 btw, I've noticed MK2 users seem to be less fortunate when it comes to reaching high clock speed).

 

[Epicenter]

Keyword: "if possible" -- it's usually not possible to run your GP2X at such high speeds. Epicenter just happens to be the lucky owner of one being able to go unusually high. Mine is stable at 290 MHz and runs for a few (10-20s) at 295 MHz before crashing (this is an MK1 btw, I've noticed MK2 users seem to be less fortunate when it comes to reaching high clock speed).

MK2 units appear to use Hynix memory, not Samsung as I recall was used in MK1 units, 1st and 2nd edition-- which tolerates less overclocking. By default the GP2X runs its 133-MHz rated memory at 100 MHz (200 MHz CPU speed), and at 266 MHz it's run at 133 MHz (its spec) hence why most units make it there with stability-- if the ARM920T can tolerate the clock. Past 266 MHz the RAM is overclocked past its spec, 133 MHz-- e.g. at 300 MHz it's at 150 MHz RAM clock. RAM's ability to handle this will dictate stability faster than the CPU will, in all likelihood.

I spoke with Vimacs about adding functionality to the existing CPU Speed and LCD Tweaker utility, changing the existing 2:1 CPU to RAM clock to something more reasonable, like 3:1 or 4:1. RAM performance will suffer if the CPU clock is not high enough to keep RAM clock close to reaching the original speed of 133 MHz though. It's possible with (or maybe without) some overvolting, a bit of luck and some divisor changes that most units could hit 300 Mhz; some units could probably hit 400 (there are ARM9s rated this high already, the architecture definitely scales that far.)