PSX software emulator on PS2

superfrog12 · Post by **superfrog12** » Mon Dec 14, 2009 7:18 pm

Hello,

Would it be possible to develop a software PSX emulator for the PS2? Is the PS2 hardware powerful enough to do this, seeing how the EE CPU is also a MIPS chip like the MIPS3000A of PSX? It is the idea so that IOP can still be accessed and used for other thing as opposed to normal PSX emulation on PS2...do you think it is possible at all?

thank you

Jim · Post by **Jim** » Mon Dec 14, 2009 11:06 pm

You can already play all your PS1 games on PS2, so what are you asking?

Jim

superfrog12 · Post by **superfrog12** » Tue Dec 15, 2009 12:28 am

hello,

i wish to save and load psx savegame to the usb stick, but i think it is impossible to do with ps2 emulation because psx games run on the IOP. i wish to know if you think it is possible technically..

thank you

yoshi314 · Post by **yoshi314** » Tue Dec 15, 2009 2:48 am

yes it is.

ps2 has already a ps1 cpu, which makes things easier (less overhead - you don't need to emulate the ps1 cpu, only the other chips). unfortunately it's used for all i/o, so you would have to somehow share it between executing r3000 code and i/o . i hope it's possible to access all ps2 memory from iop - that would make things much easier, and free up some iop ram for other purposes.

protomank · Post by **protomank** » Tue Dec 15, 2009 4:31 am

Potentially, a PSX emu for PS2 could be like the ones from PC that even improve speed and graphics:
- no need to emulate CPU
- more ram and vram
- but needs to emulate the GPU, so the graphics can be improved.

I think no one will be doing this, but it is fun as a "science school project" :D

cosmito · Post by **cosmito** » Tue Dec 15, 2009 9:51 am

protomank wrote:Potentially, a PSX emu for PS2 could be like the ones from PC that even improve speed and graphics:
- no need to emulate CPU
- more ram and vram
- but needs to emulate the GPU, so the graphics can be improved.

I think no one will be doing this, but it is fun as a "science school project" :D

Actually one fellow is doing it, ffgriever. Don't have any info regarding its progress, but judging by his proven expertise, I should rock.

dlanor · Post by **dlanor** » Fri Dec 18, 2009 8:53 pm

It is indeed true that ffgriever has written an emulator known as PS2PSXe, which as yet is available only to a limited set of handpicked beta testers, including myself.

This emulator already has the same level of compatibility as the emulators for PC known as PCSX and ePSXe, which means that nearly all games work with near perfect graphic rendering. And a new workaround unique to this emulator even allows most sub-channel protected games to run even if the sub-channel files are missing (as for non-CCD rip attempts).

But PS2PSXe has no real sound implementation at all yet, but only a dummy SPU unit (to prevent lockup for audio functions).

And the emulator is still quite slow in many games (especially for 3D engines).

So a proper SPU implementation and a speed-optimized GPU reimplementation were the next steps in the original plan (appx a year ago !!!). But then other things intervened causing ffgriever to invest his time in other projects instead (notably the ESR method for backup games and the recent translations of the games "Okami" and "FF12 IZJS").

I sincerely hope that he will have time to take up work on the PS2PSXe project again (and soon), as it is a great project which deserves a public release ASAP. (IMO even without the speed and SPU improvements...)

Best regards: dlanor

yoshi314 · Post by **yoshi314** » Sat Dec 19, 2009 10:30 pm

i'm still wondering, if ffg has trust about his beta testers (because there was no leaked copy of the emulator, i figure he picked out right people), why doesn't he invite some more accomplished ps2 homebrew devs to help out with development?

superfrog12 · Post by **superfrog12** » Sun Dec 20, 2009 3:07 am

maybe because there is not many accomplished ps2 developer left? i think in this forum in early times there was alot very knowledgeable people like mr.brown, gustavo and herben and some other, but they all move on long time ago, no? if you look at old threads you will find very many interesting ones, but today not so much anymore.

but maybe he could just make it open source so everyone who likes can take a look or is there a reason against it?

cosmito · Post by **cosmito** » Sun Dec 20, 2009 8:53 am

superfrog12 wrote:maybe because there is not many accomplished ps2 developer left? i think in this forum in early times there was alot very knowledgeable people like mr.brown, gustavo and herben and some other, but they all move on long time ago, no? if you look at old threads you will find very many interesting ones, but today not so much anymore.

I see what you meant although you're not correct. There is some development still for the PS2 by devs like misfire, ifcaro, jimmikaelkael, ragnarok2040, EEUG, dlanor, Mega Man and some others I'm forgeting and even old times PS2 gurus still working in their free time. Ps2Linux, Open PS2, FMCB, ESR, IGR, GS Mode Seletor are big achievements and ongoing projects. Even myself - although I'm nowhere near the level of the fellows above - I'm (very) slowly updating Lukasz Doom port from the SDL version, limited by my lack of decent free time and dreaming of doing some other projects (on a perfect world where you could have all the free time you wanted :) ).

But yes, the PSP is more appealing these days (more decent to program/debug?) and there are a lot of more active developers, but I strongly believe the PS2 has the best crew.

And JF, c'mone, time to return to the PS2 ;)

----- edited-------

Well, to be honest, the PSP scene have also excellent coders but the number of those seems to me similar to the number of PS2 devs.

superfrog12 wrote:but maybe he could just make it open source so everyone who likes can take a look or is there a reason against it?

Maybe if he's interested it would be a good idea for him to call for colaborations, but only he can pronounce about this...