Investigating the PSP's PSone emulator

As Sony laments another security breach.

When the Sony PSP launched in Japan at the tail end of 2004, it looked set to dominate handheld gaming for the foreseeable future. The machine had it all: ultra-desirability, state-of-the-art specs, all-encompassing support from all major publishers, plus every major Sony and third party gaming franchise on the way. But a combination of shovelware PS2 ports, a basic lack of understanding as to what is required from a handheld game experience and a high price point has held the machine back dramatically. At the same time, Nintendo's DS has caught the imagination in a way that Sony seems unable to match.

With the PSP more than a little moribund, Sony has plunged an adrenalin-packed syringe of extra functionality directly into the heart of the machine, injecting new features deep into its advanced innards. Most exciting of these new upgrades is the PlayStation 1 emulator. A core component of the PS3-interfacing firmware 3.0, it is one of the most ambitious and complex pieces of code yet devised for the PSP. Original PlayStation titles can be bought and downloaded from the PlayStation Store via PS3, downloaded to memory stick then played on the handheld. And the emulation performance is astonishingly good, as close to perfect as you could want, with only minor glitches being reported on a minority of titles.

A software design classic

While many were expecting the PS1 titles available on the Store to be ported to the PSP with modifications, the downloaded code is actually 100% identical to the titles that were released on CD all those years go, with the PSP itself completely emulating the base hardware. Potential problems such as the lack of all of the original joypad functions are all addressed internally by the emulator, which offers several button remapping options. Most PS1 titles run at a humble 256x224 resolution and the emulator can match that, but additionally offers options to scale up the image 18% to fill the screen at the original aspect ratio, or else stretch the image to fill the PSP's 480x272 widescreen display.

'Investigating the PSP's PSone emulator' Screenshot 1

What would you play?

The coding is pretty much a work of genius - there's strong evidence that the PSP's MIPS R4000-based CPU is running most of the PS1's R3000 code natively, but it's highly likely that the rest of the PS1 hardware is being emulated entirely by software. Some of the compatibility glitches with certain titles look very similar to those witnessed in the aged Macintosh Connectix Virtual Game Station emulator, released back in 1999. This codebase was bought by Sony (mostly to get it off the shelves) but it may well be that elements of that product have found their way into the PSP code. What is for certain is that this is the most demanding PSP code ever written. All games released to date run with the CPU locked at 222MHz, but the emulator dynamically changes the CPU speed to cope with the load and it is the only piece of software ever to run the PSP CPU at its top speed of 333MHz when performing really complex tasks.

What this essentially means is that the PSP - unofficially, for now - has access to a colossal library of brilliant games, making the handheld an essential buy. Final Fantasies VII-IX, Metal Gear Solid, Vagrant Story, Gran Turismo 1 and 2, Tekken 3, Xenogears, Resident Evil, Castlevania: Symphony of the Night... the list of gaming titans potentially available for handheld play is beyond sensational. The only issues are that - officially at least - you can only play these titles if they're available to buy in the PlayStation Store, and if you own a PS3, required to access the Store in the first place.

Of course, there's also the factor of money. Each game costs US$ 5.99 to download, which would be fair enough were it not for the fact that you might already have bought the original PS1 title. It could be argued that effectively charging for this service is good business sense from Sony, and earning additional revenue from back catalogue content is something the movie and music industries have been doing for decades. On the other hand, spending so much time and effort on such a monumental piece of code and then basically hobbling its potential is a little puzzling when the PSP really needs all the help it can get in improving its fortunes. Over and above the money issue, the PS3 ownership prerequisite in particular is another extremely bizarre limitation considering how low the crossover in ownership must be.

Emulator exploitation

'Investigating the PSP's PSone emulator' Screenshot 2

Speed Freaks? Correct.

Unfortunately for Sony, Christmas was hardly a season of good tidings. The PSP's security, now completely compromised, makes the reverse-engineering of any internal software module very easy for those programmers in the know. Spanish PSP code warrior, Dark Alex, having already released his own piracy-friendly firmware update, released a completely open PlayStation emulator update on Christmas Day, which offers extreme levels of compatibility with well over 90% of all NTSC PlayStation titles. Over and above the work done on defeating the PSP's internal security, the hack works simply by bypassing a security checksum and diverting a license key check. Also released was a tool that allows you to copy your own PlayStation titles into PSP friendly memory stick files for playback on the emulator.

Not surprisingly, even those with zero interest in piracy want in on the action here. Despite many PS1 titles obviously showing their age 12 years after the system's debut, there are so many solid gold gaming experiences to be savoured on the PSP that Dark Alex's custom firmware build is now a supremely hot download. Hardcore gamers, having turned their back on the Sony handheld, are now coming back in their droves, digging out their dormant PS1 collections and replaying some classic slices of videogaming history, or even chasing down games they might have missed in the past in order to play them for the first time on the PSP.

How Sony chose to respond to this Yuletide guerrilla assault on their PS1 back catalogue plans turned out to be pretty predictable. The latest firmware 3.10 featured new PlayStation emulator code, a couple of security patches and a new set of encryption keys (which were broken before the US version of the firmware was even released). But perhaps someone at Sony is witnessing the wave of good will and excitement surrounding PS1 emulation and you have to wonder - would it hurt their plans so much to sell their own PS1 CD conversion tool supported by their own official firmware?

Comments (80) Latest comment 5 years ago

Comments threads automatically close after 30 days, but please feel free to continue chatting on the forum!

  • Blerk #1 5 years ago

    would it hurt their plans so much to sell their own PS1 CD conversion tool supported by their own official firmware?

    No. In fact, it might even make me consider a PSP.

    Actually it wouldn't, but that wouldn't make for a very good post. :-D
  • Dizzy #2 5 years ago

    Image how well the PSP could have done if it was PS1 compatible out of the box.
  • pooboysam #3 5 years ago

    All very odd considering the PS3 positively encourages homebrew software via it's Linux compatibility!
  • Aretak #4 5 years ago

    I'm currently playing through Final Fantasy IX on my PSP. ^_^
  • trevd72 #5 5 years ago

    you need the ntsc iso's to play them on the psp at the moment so you cant use your own old games. It is very good being able to play FF:T on the PSP and my bro' loves GT so he is over the moon to be able to play that again on the bog.

    Remember folks its copyright infringement not copyright theft no matter what those nazis at FAST say.
  • Eldritch #6 5 years ago

    I'm not going to buy a PS3 to play PSone games on my PSP.

    Sorry, Sony, too much of a rip-off.
  • Steroyd #7 5 years ago

    Surely if the PSone emulator has been compromised fully they might as well do direct to PSP now, to stop leaking as much profits as possible?
    Edited by 1 at 02/02/07 @ 11:41
  • Nobuo #8 5 years ago

    Isn't it 'FACT'?

    I don't think anybody in the world is going to buy a PS3 just for this. So given the aforementioned low crossover until they release their own game conversion tool or open up the store to PSP owners they're not gaining any sales.
  • Nobuo #9 5 years ago

    "Surely if the PSone emulator has been compromised fully they might as well do direct to PSP now, to stop leaking as much profits as possible?"

    Good point.
  • TheMoonRat #10 5 years ago

    How does it handle the lack of L2 / R2 on the PSP?
  • Steroyd #11 5 years ago

    Personally i was hoping Sony would allow to legitimately copy PS1 games onto the PS3 hard drive and beam it to the PSP that way i don't have to get the fragile PSone discs out, and I would enjoy software emulation, and i wouldn't have to re-buy the PS1 game from the PSN store.

    It's a shame that it would have to take a homebrew junkie to do it...
  • tentonipete #12 5 years ago

    so if you've payed for the game, and you're emulating it on a system you have also paid for, where's the crime?
  • El_MUERkO #13 5 years ago

    custom firmware ftw
  • Steroyd #14 5 years ago

    so if you've payed for the game, and you're emulating it on a system you have also paid for, where's the crime?

    What's to stop people from copying the ISO or whatever file types the emulator reads?
  • valli #15 5 years ago

    "you need the ntsc iso's to play them on the psp at the moment so you cant use your own old games."

    There are tools that convert PAL to NTSC titles, even the "official" converter from Dark_Alex supports that.

    Excellent suggestion for Sony to release the conversion tool and let us transfer the PS1 discs ourselves. Mind you, the homebrew scene is way ahead with amazing features such as PS1 ISO compression and support for multi-CD titles.
  • dirigiblebill #16 5 years ago

    @ bigo

    Because people want to play these classics on the bog. It seems to be the Holy Grail of gaming ;)
  • Rambaldi #17 5 years ago

    Spend about £600 on a PS3 and a PSP to play PS1 games?

    Why not buy a PS1?

    THIS is Sony's answer to it's PSP failures?
    Edited by 1 at 02/02/07 @ 11:59
  • lost_soul #18 5 years ago

    You can convert PS1 games from PAL to NTSC. I had to convert my copies of FF8 and 9 to get them working.
  • BradlayLaw #19 5 years ago

    "you need the ntsc iso's to play them on the psp at the moment so you cant use your own old games."

    There is a tool that can convert a PAL game to NTSC. I did it with my copy of Wip3out SE. Now all I need is a bigger memory stick so that I can actually play the thing :(
  • Steroyd #20 5 years ago

    @Rambaldi

    The PSone is not portable.
  • MadMirko #21 5 years ago

    The PSone is not portable.

    To be fair, the PSP is only portable around your home because it is easily damaged and power hungry as well.

    Anyway, homebrew FTW!
  • Aretak #22 5 years ago

    "How does it handle the lack of L2 / R2 on the PSP?"

    There are four different control schemes, but the only two I've found use for are 1 and 4. In the former, L2 and R2 are mapped to left and right on the analogue nub (up being them both together), while in the latter the analogue nub is used for movement, and L2 and R2 are on the d-pad.

    The fact that the PSP's d-pad is utterly rubbish has meant I've been using the analogue nub for movement in most games, but it's a pain in the ass for menus in Final Fantasy. Forunately, swapping between them is very quick and easy.
  • MadMirko #23 5 years ago

    Anyone any ideas when we non-firmware hacking PSP owners can download PS1 games without a PS3 sat in the middle?

    That is not going to happen. The PS3 is in there to ensure you obey the DRM rules.
  • dirigiblebill #24 5 years ago

    @ AlMcD

    Probably once the psp has given the ps3 enough of a leg-up in this regard for it to start selling well by itself.
  • Steroyd #25 5 years ago

    wait... aren't you gazumped if you decide to suddenly play through MGS1 with Psycho Mantis and all.

    That must be a bitch.

    That is not going to happen. The PS3 is in there to ensure you obey the DRM rules.

    Yes but surely Sony knows that they're limiting the availability of who can download the Psone downloads online...
    Oh PS1 you was riddled with piracy while you were hardware now you live on in Software to.
    Edited by 1 at 02/02/07 @ 12:14
  • sport #26 5 years ago

    meh...

    sort out the ergonomics Sony - I'm tired of people making fun of my spasmed hands
  • Jonsend #27 5 years ago

    I wasn't really interested in the homebrew despite trying it out early on and didn't pirate games so I upgraded my firmware, but I regretted upgrading once people managed to play PS1 games on their unofficial firmwares. Thankfully the 3.03 downgrader came out and I am now playing Resi 3, Vagrant Story and FFIX and they look and run fantastically. I think I'll be hitting ebay soon to see what bargains I can find.
  • Garulon #28 5 years ago

    "All very odd considering the PS3 positively encourages homebrew software via it's Linux compatibility!"

    Except it's Linux support is so horribly gimped you'd have trouble emulating a SNES on the thing, let alone a PS1.
  • Aretak #29 5 years ago

    "wait... aren't you gazumped if you decide to suddenly play through MGS1 with Psycho Mantis and all.

    That must be a bitch."


    You can beat Psycho Mantis without using the controller trick. It involves destroying some statues in the room. The Colonel tells you about it if you bug him enough.

    The far bigger problem with multi-disc games like MGS which don't let you save at the end of the disc (as opposed to those like Final Fantasy VII-IX and Xenogears which do), is that there's currently no way to save and move onto the next disc.

    I believe there's a workaround for MGS, and both discs of Parasite Eve can be combined into one EBOOT, but for games like Star Ocean: The Second Story you're screwed for now. The only way to do it is to export your save game from the PSP, play past the disc swap in something like ePSXe on your PC, and then continue on the PSP.

    Or download a save game at the start of the second disc, of course.
  • [maven] #30 5 years ago

    Dizzy:
    I'm not sure if the PSP would be better off if this were available at launch, because Sony wanted (and for good reason) people to think of the PSP as "the power of a PS2 in your hand", and maybe the availability of PS1 emulation would've undermined that. It could also have helped immensely; but we'll never know...
  • Eldritch #31 5 years ago

    "To be fair, the PSP is only portable around your home because it is easily damaged and power hungry as well."

    No.
  • Nobuo #32 5 years ago

    "You can beat Psycho Mantis without using the controller trick. It involves destroying some statues in the room. The Colonel tells you about it if you bug him enough."

    OOH! Didn't know that one.

    You could just try and beat him without tricks, but that's pretty damn tough on the harder difficulties.
  • SBfistfun #33 5 years ago

  • repairmanjack #34 5 years ago

    If they ever get their thumb out of their arse and knock the PS3 out of the loop, I'll be playing FFVII and VIII, Driver, Tenchu and Civ2. Even if they wanted £5 per title (which they will, based on the Sony exchange rate principle).
  • MadMirko #35 5 years ago

    DRM exists on PC as well, you know.

    The point is, it doesn't exist on the PSP. Anymore. Now with guaranteed hacking of every coming PSP firmware...
  • grandmaster Verified Director, Digital Foundry #36 5 years ago

    With regards the point about the custom firmware offering compression whereas the original downloads from the PlayStation Store don't... well that's incorrect. Compare the Tekken 2 download to your Tekken 2 uncompressed rip. The official download is much smaller.

    So the official downloads had realtime decompression on the fly "first", if you will.
  • darkmistx #37 5 years ago

    Garulon: "Except it's Linux support is so horribly gimped you'd have trouble emulating a SNES on the thing, let alone a PS1."

    How is ps3 linux support gimped? Serious question btw.
  • Blerk #38 5 years ago

    How is ps3 linux support gimped? Serious question btw.

    There's not much memory available after the OS has loaded and access to the 3D bits of the RSX isn't supported so you can only really do 2D stuff.
  • MadMirko #39 5 years ago

    Al, you don't have to take my word for it. Just watch it (not) happen. :)
  • trevd72 #40 5 years ago

  • trevd72 #41 5 years ago

    @valli did not know that, cheers.
  • trevd72 #42 5 years ago

    the compression from the store is better than what we can do at the moment. i have used a tool that takes out the blank data but it still did not beat the official rom.
  • trevd72 #43 5 years ago

    the compression from the store is better than what we can do at the moment. i have used a tool that takes out the blank data but it still did not beat the official rom.
  • zErOb_cOOl #44 5 years ago

    I'm all for people using hardware, THAT THEY'VE BOUGHT THEMSELVES AND OWN, for whatever they want. I'm sick of all the restricions put on hardware, and the crippling of software, just to meet a company's marketing strategy.

    I think console manufacturers should simply count themselves lucky that so many people buy their consoles (considering the high price of most of them, this time around especially) and count any post games sales as a bonus. Not a very proactive view in terms of the future of the games industry, but a fair and realistic one I feel.
    Edited by 1 at 02/02/07 @ 13:30
  • nuffmon #45 5 years ago

    If $5.99 translates to pounds well then i'm not too bothered about paying for a game i already own. I just want to be able to download them without a PS3. Although i will be buying one shortly after launch....hopefully.
  • getinthereson #46 5 years ago

    To be fair, the PSP is only portable around your home because it is easily damaged and power hungry as well.

    Does me for my 2 hours of commuting every day thank you very much...
    Edited by 1 at 02/02/07 @ 13:56
  • MoGamer2006 #47 5 years ago

    My DS does me for 3 hours commuting every day for a week.... I only recharge it on Sunday night ready for Monday morning...

  • trav #48 5 years ago

    I do love my DS to pieces. Playing Phoenix Wright 2 and Elite Beat Agents at the mo on the commute to work.

    But being able to play Castlevania SOTN, Resident Evil, Chrono Trigger, Xenogears, Fear Effect and some of the other fantastic games on the PSOne... on the go. That just spells win for me.
  • Rev.StuartCampbell #49 5 years ago

    The reason Sony are terrified of releasing licenced conversion software is that it'd cripple sales of PSP games. Most of them are tired shovelware, whereas the PS1's back catalogue is stuffed with hundreds of fantastic, inventive games, including lots of stuff that was never legitimately released over here. I've converted over 120 titles across for myself and my WoS subscribers (who own the originals, of course), and no native PSP game has had a look-in for the last three weeks. Even working through just the cream of the PS1's history would take years, and that's time that you're not buying overpriced PSP games. Sony would be committing suicide.
  • Ryze #50 5 years ago

    I've never wanted to play my PSP for 6 hours in a single day, therefore the battery has never run out on me.

    It's survived trips to Greece and Amsterdam, where it's been out and about (in Amsterdam) in the soft case in my pocket, and in my hands being played in bars, coffeeshops, train stations, airports and the hotel.

    No need to take it anywhere in Greece, as there's girls and sunshine to enjoy, plus we don't have the GPS in Europe yet!!! :-( It was sweet watching Jarhead on the plane last summer, while everyone else had to settle for that 'Tim Allen turning into a dog' bullshit.

    I even dropped it at Manchester airport, while sat in the departure lounge. Then I picked it up and carried on playing Liberty City Stories, Mario Kart and Burnout Legends.

    No damage. Just use the Hori screen protector and put it in the soft case when ur done.

    Sort out the Ergonomics and the controls, Sony.
  • F1Tom #51 5 years ago

    @ Rev.
    But it is time to be buying shed loads of ps1 titles which equals .......$$$$$$$
    Edited by 1 at 02/02/07 @ 14:57
  • Ryze #52 5 years ago

    @ bigo

    + RSI - For all of the Playstation controllers, plus especially the PSP.

    And the NES and Master System pads.

    Plus thumb injuries from the original Mega Drive pad.

    ;-) Sony continues to fumble.
    Edited by 1 at 02/02/07 @ 15:02
  • dirigiblebill #53 5 years ago

    @ bigo

    I think it's some kind of mental-focus thing.

    /dons beard

    'Men are never so serious, thoughtful and intent, as when they are At Stool.' (Gulliver's Travels)

    /shaves

    Let me know how the DVT claim pans out.
  • SeesThroughAll #54 5 years ago

    I'm not going to buy a PS3 to play PSone games on my PSP.

    How about for playing PSOne, PS2 and PS3 games?
  • Rev.StuartCampbell #55 5 years ago

    "But it is time to be buying shed loads of ps1 titles which equals .......$$$$$$$"

    Only for game stores, though. 99% of PS1 games bought nowadays will be bought second-hand, meaning not a penny in income for Sony.
  • Rambaldi #56 5 years ago

    @Steroyd

    "The PSone is not portable"

    Indeed, but if a portable PS1 was created it would cost a damn sight less than the price of a PS3 and a PSP..£600 to play PS1 games on the go is a joke.

    Heck, a portable PS1 should be about HALF the price of a PSP, which is effectively a portable PS2.

  • Rambaldi #57 5 years ago

    "i'm not too bothered about paying for a game i already own"

    Don't say that kind of shit, please: you never know how many publishers are listening.
  • Dizzy #58 5 years ago

  • Gurgeh #59 5 years ago

    Well Sony need to do something for the PSP, look at all the DS titles:

    Japanese top twenty software titles:
    01. Grand Theft Auto: San Andreas (PS2)
    02. Dragon Quest Monsters Joker (DS)
    03. Sangokushi Taisen DS (DS)
    04. Picross DS (DS)
    05. Hotel Dusk: Room 215 (DS)
    06. Wii Sports (Wii)
    07. Wario: The Seven (DS)
    08. Wii Play (Wii)
    09. Pachinko Winter Sonata (PS2)
    10. More Brain Age (DS)
    11. New Super Mario Bros. (DS)
    12. Common Knowledge Training (DS)
    13. Animal Crossing: Wild World (DS)
    14. Prince of Tennis: Doki-Doki Survival (DS)
    15. The Idolm@ster (Xbox 360)
    16. Mario Kart DS (DS)
    17. Pokemon Diamond (DS)
    18. English Training (DS)
    19. Brain Training (DS)
    20. Shining Force EXA (PS2)
  • dirigiblebill #60 5 years ago

    I'm assuming nobody on this thread would buy a psp/ps3 *just* for the ps1 back-catalogue. Do I assume correctly? Because that would be a bit thick now wouldn't it.
  • dirigiblebill #61 5 years ago

    @ Gurgeh

    ???? Whose top twenty, and in terms of what? Christmas sales?

    Good name btw. Now what was that drone's name again. The one that nails the emperor right between the eyes with a reflected lazer beam.
  • Gurgeh #62 5 years ago

  • J_C_X #63 5 years ago

    I put Chrono Cross on mine. I own the game so technicaly I'm not doing anything illegal. It is so easy to do the only problem is you have to download a game you don't want.
  • Avaloner #64 5 years ago

    All the security measures taken by sony to stop people from pirating the games is doing nothing to stop the pirates, and everything to stop us legit users from enjoying the system. At this point I am regretting going the lawful way.
  • Les #65 5 years ago

    "£600 to play PS1 games on the go is a joke."

    Not much more of a joke than paying to play free flash games on your console...
  • Rev.StuartCampbell #66 5 years ago

    "All the security measures taken by sony to stop people from pirating the games is doing nothing to stop the pirates, and everything to stop us legit users from enjoying the system. At this point I am regretting going the lawful way."

    I hope you've learned a lesson there.
  • MadMirko #67 5 years ago

    "£600 to play PS1 games on the go is a joke."

    Not much more of a joke than paying to play free flash games on your console...


    Or not much less. People currently buying a PS3 are not buying because of anyhting that it IS, they buy because of what they hope it WILL BE.

    Which is stupid if you ask me, but who does? :)
  • Les #68 5 years ago

    "People currently buying a PS3 are not buying because of anyhting that it IS, they buy because of what they hope it WILL BE."

    That goes for every console. Look at the idiots that bought a 360 at launch. A full year later and nothing special (aka next gen) has been released yet (which isn't that surprising as it's just an xbox with a graphics update). And still there's lots of people 'enjoying' it. They've payed lots of money for it and will do everything to convice themselves it was a good buy. Same will go for PS3. Once people have bought the system and the 'next-gen' games never show up, they will slowly forget about it and get all excited again when the next 'next-gen' starts (probably somewhere 2008). People are short sighted idiots. That's why marketing works.
  • spongebob #69 5 years ago

    MS is doing great on the games front according to that Japanese sales list ;)
  • Rambaldi #70 5 years ago

    Now if Sony said you could download any PS1 game via their web-site, bang it on a memory stick and play in your PSP...

    Heck, I'd even buy a PSP if that were the case!

    This forced route via the PS3 smacks of a fine mixture between desperation and short-sighted greed.
  • thefilthandthefury #71 5 years ago

    @ Les

    Too poor for a 360 huh? :)
    Edited by 1 at 03/02/07 @ 21:02
  • rez606 #72 5 years ago

    so the playstation portable is now a "ps + ps3 + download service even though you own the game already portable"... :o(

    so sega how about a saturn compilation to follow up the mega drive one on psp...
  • zendragon #73 5 years ago

    how playable are the controls?
  • dirigiblebill #74 5 years ago

    What the hell is 'Id@lmaster'? and since when did the Japanese go for GTA?

    I'd say there's plenty of good software available on psp these days without plumbing the ps1 era. Maybe it isn't the most cosmic of lineups, but it's more than enough to justify owning one.
  • ph101 #75 5 years ago

    I have to say that is some very bloody minded marketing right there. That the PSP has already been hacked to do this, and to try and get PS3 sales off the back of the emulator is actually staggering. Sony is clearly being run by some very silly people and if I was a shareholder I would not be happy. But good luck to them. Spore is coming out on the DS, yay!
  • Dr_Evil #76 5 years ago

    So, what PS1 games are worth playing - and playable - on the PSP?
  • miiiguel #77 5 years ago

    I haven't touched my PSP for about 4 months. Anyone want to buy it ?
  • jonsaan #78 5 years ago

    ooooh. Ps1 games. Wobbly 3d on my lovely psp. I can't wait.
    Edited by 1 at 05/02/07 @ 17:19
  • -TKF- #79 5 years ago

    Fantastic, a nice piece on the PSP turns into how much of your life you waste going to and from work.

    Anyone running out of juice on their PSP going to and from work should find a new fucking work.
  • dryden555 #80 5 years ago

    the sole thing that would make me to buy a PSP is the ability to play ps1 games on it while I'm on a plane etc. Shame SONY doesnt make it easier. I'm not buying a PS3 to make this work. Bizarre of Sony to think anyone would.