Why does the PSP support PSX games ?

[meesbaker]

Ive been doing some research on that but only found how to do it not why its possible. I used to think that the games are emulated and didnt really wonder as it works even on ipod touch quite well.

However, I found out that the games are converted to PSP bootable files, also graphics and sounds are very native. Even when troubleshooting mods the PSP behaves much more like a PSX while emulators are much more forgiving.

Do I get this correctly that a PSP natively supports PSX games? How is that possible, they are technically different from what I read on wikipedia while the PSP processor should not be powerful enough to emulate a PSX game. Im confused.

[Rundas]

Not powerful enough? I doubt the psx has a better processor than the psp.

[luksy]

The PSP's processor has a similar architecture to the PS1 and probably runs a lot of the original code natively, everything else is emulated http://www.eurogamer.net/articles/investigating-the-psps-psone-emulator-article

[meesbaker]

So its an emulator after all, interesting stuff. As you can see they are suprised as well, calling the emulator running so well a masterpiece of coding and assuming the similiar cpu architecture could make things easier.

Basically I thought it should be impossible when I saw the PSP processor running at like 220 mhz on wikipedia. Sure the PSX processor is weaker but emulating a system always takes much more power especially emulating every aspect of it and even doing so well and in high quality.

The emu on my ipod mostly runs slow and has strange sound. Its nowhere comparable to the PSP although the processor in my device should run like 600-700mhz.

I think the article gives the answers: A close processor architecture, cpu clocked to 330mhz and badass coding by Sony

The last thing of course is very important. I totally forgot that the PSP runs the PSN games. I used to think that the PSP just happened to play ISOs for some reason with some plugin and custom firmware and didnt get how that could be. Of course Sony planned this and intentionally included this feature THATS something different. Sony has different capacities and the best understanding of how the PSX works, sure they could handle it. Still I believe the PSPs processor has a lot to do with it as well. Playing Ffvii on ps3, some sounds like sephs sword are strange, on the psp they arent. Its obviously easier to program PSX emulation for the handheld than for the cell.

[Rundas]

That's the thing, since they share the same architecture you don't need more power than an actual ps1 because there is no translation going on. Unlike emulating a ps3 where you would have to turn its cell architecture into something your computer could understand.

[meesbaker]

Very nice in my country the oldest psp 1000 is like 20 bucks on ebay I may get one. Custom fw playing my modded isos anywhere

[nfitc1]

I'm still trying to get any PSX game running on my PSP.

[Bosola]

The CPU isn't emulated - they're both MIPS architectures, with the PSP's processor instruction set being a superset of that supported by the PSX.

I don't know much about the popstation 'emulator', but I would expect a compatibility layer for mid-level graphics and sound calls. This isn't really 'emulation' - it's more a matter of providing an API that fulfils the same contracts as the original hardware. Naturally, undocumented behaviour or quirks might not supported, which may explain why certain games are hard to port.

There wouldn't really be much 'extra' processing required to intercept the hardware calls. Yes, the requests would be deferred through an abstraction layer, or some kind of memory sandbox mapping for low-level operations, but you shouldn't be doing anything _that_ 'intensive'.

And remember, even recompiling assembler can be performant if you cache generated procedures and do smart optimization / branch prediction etc. Just look at the JVM - Java applications are essentially "compiled" to a generic assembler for an 'idealized' processor architecture, then reinterpreted on the fly via the virtual machine. Java 1.0's naive implementation was pretty slow, but since hotspot speed has been mostly a non-issue.

[meesbaker]

@Bosola thanks for the expert stuff I was searching google for such an article as I knew that it wasnt just a simple emulation like epsxe now I get it thx

@NFITC1(this time I paid attention^^) any PSX game? The Grand Master himself ?
I have to say I havent tried it but here is my humble knowledge:
The PSP boots games from PSN which are 100% clones of the PSX isos just compressed to a PSN eboot. As FF7 is on PSN you can easily get it to work on psp just like the ps3 does when you copy it over to your device. You dont even need popsloader plugin if you use PSX2PSP to convert your PSX ISO to an eboot and put it in the right root location.(/GAMES or so)

The game will appear in your xmb and will be executable just like a PSN ff7, there is no difference.
At least thats what I read in an article about easy PSX gaming on PSP- may be full of crap though

[DLPB_]

On the question of CPU power, the PSP uses 333 MHz MIPS R4000
The PSX uses MIPS R3000 33.8688 MHz

if wiki is right.

[dkma841]

I'm still trying to get any PSX game running on my PSP.

What's your psp model and what firmware and hacked with? I used to hack loads of psp's for people and get psx games working and that etc before but that was kinda a long time ago so lost some touch forgot stuff, you should check youtube for tutorials on the model, firmware and hack for psx isos

I still got a psp 3000 hacked preloaded with games on a 16gb i think but couldn't play it for years kos i don't have another battery and hard to find an official one Only find unofficial fake ones, tried em and they're shit works for an hour then bam never charges again..
Psp's won't die easily it's a great handheld console when hacked play alot of snes games on it etc

[nfitc1]

What's your psp model and what firmware and hacked with? I used to hack loads of psp's for people and get psx games working and that etc before but that was kinda a long time ago so lost some touch forgot stuff, you should check youtube for tutorials on the model, firmware and hack for psx isos

I still got a psp 3000 hacked preloaded with games on a 16gb i think but couldn't play it for years kos i don't have another battery and hard to find an official one Only find unofficial fake ones, tried em and they're sh*t works for an hour then bam never charges again..
Psp's won't die easily it's a great handheld console when hacked play alot of snes games on it etc

It's a 3000 with 6.60 CFW. I don't have more details at the moment.

[dkma841]

It's a 3000 with 6.60 CFW. I don't have more details at the moment.

http://www.youtube.com/watch?v=Wnsp3CJ2LfU
You need ProB9 version of 6.6 CFW to play PSX games on it dunno why but it's just like that there are B8 or lower version for 6.6 but B9 is the one that'l work If that don't work then B10 6.6
That vid shows instructions aswell etc how to get popstation in it and might help sometimes to format the mem stick first

[meesbaker]

Why is it that complicated anyway ? Any PSP plays psx games from psn right ? I thought custom fw is only needed to access the filesystem but then why we need popstation ?

Cant we just convert an iso the same way as the eboots on psn and put them in the same location ?

[Tekkie.X]

I have one of the wifi-less E-1000s(I think that's the model), piss easy to put CFW on it, just copy onto the mem card and run it, if the battery runs out or you switch it fully off, you can run it again with ease, I then spent a few days converting some of my PS1 collection to EBOOTs.

[nfitc1]

Why is it that complicated anyway ? Any PSP plays psx games from psn right ? I thought custom fw is only needed to access the filesystem but then why we need popstation ?

Cant we just convert an iso the same way as the eboots on psn and put them in the same location ?

That's what we try to do, but there's a few layers of security around the eboots that need to be...bypassed. It's like digital signatures. If the PSP doesn't have that signature on an eboot it won't load it (or even acknowledge it). The CFW either bypasses the need for signatures or flags them all as acceptable and tries to load them.

[meesbaker]

Ah I see so thats the purpose of Popstation. Is that even legal? I remember some discussion that even esr playing backups we own was illegal although making a backup and using fmcb is not.

Some people said there was some law or a condition in some terms of use that forbid to get around any kind of copy protection. As ESR bypasses the pa2's copy protection its use was illegal isnt popstation the same then ?

By the way some people seem to have given me Karma today Im starting to become prominent

[sithlord48]

i've had mixed results with converting my psx games from disc to eboot . i've gotten a few of my games to work I.Q and Castlevania SOTN  work but i can't seam to get FF7 to work.

[nfitc1]

Ah I see so thats the purpose of Popstation. Is that even legal? I remember some discussion that even esr playing backups we own was illegal although making a backup and using fmcb is not.

It's a violation of some "agreements" you made when purchasing a PSP. Legally there's no way for them to sue you over it, but you can consider your warranty void. There are issues with you playing your backups as well. Akin to "multiple copies of a single license" laws. Backups are only supposed to be backups and not intended to be used while the main media is functional.
It's like copying a VHS or DVD and watching one while on a vacation while the original is sitting at home. That's illegal....for some reason.