Homebrew for PSP Publishers

starman2049 · Post by **starman2049** » Tue May 16, 2006 9:25 am

This is kind of off-topic, and I hope I don't get booted for asking this, but I was showing my game on PSP Homebrew at E3 and several publishers were interested in getting a copy of my game on PSP for internal evaluation. Question is how to do this?

I assume that if you are a licensed publisher you would have some sort of "debug" PSP that will play un-encrypted/unsigned executables generated from homebrew, and so what I would do is fork out $20 for a small Memory Stick duo and just send it out on mem card. Has anyone done this? Does anyone have any other ideas?

I wonder if I could send them a copy of the game zipped up with all of the file I/O "ms0:..." references replaced with whatever it would be for access to the UMD drive, but that sounds like a real shot in the dark and would probably be just as likely/unikely to run as sending a mem card.

Any ideas/suggestions would be GREATLY appreciated!!

dot_blank · Post by **dot_blank** » Tue May 16, 2006 12:13 pm

your best bet is to go ahead and get that cheap memstick
after all the DEM-100 units do have memstick slots and can
easily run any unsigned elfs/prxs ....after all thats what is made
on them :P ...right up until sony signs em

starman2049 · Post by **starman2049** » Tue May 16, 2006 12:29 pm

thank you!!

PlayfulPuppy · Post by **PlayfulPuppy** » Tue May 16, 2006 8:48 pm

You don't have to bother with the memory sticks, the dev units can load data off a remote host.

Just get rid of the KXploit and you should be able to just email it to them (Although turning up with it burnt onto a CD would probably be more professional. ;))

edit: Oh, and as far as I know you'll need either an ELF or a PRX, NOT a PBP.

Jabberwocky · Post by **Jabberwocky** » Tue May 16, 2006 10:01 pm

You'd need to remove any exploit code from your game and also get it to load your data from host0: rather than the memory stick. The devkits will run PRX or ELF, but make sure they're user mode and not kernel.

The best way to test would be to get your game running as a PRX using psplink. As psplink does all the exploit setup for you, the PRX should be clean and perfect for a devkit. Also you can get everything loading from host0: through psplink, which is what you'd expect to see on a devkit.

Best of luck to you, hope you get somewhere with it.

-Jw

subbie · Post by **subbie** » Tue May 16, 2006 11:50 pm

What about using the trick to turn it into a bootable iso. Then just send it to them on a dvd to use on the devkit?

starman2049 · Post by **starman2049** » Wed May 17, 2006 5:01 am

Looks like there's a variety of ways to do this. My main concern was that there might not be *any* way to do this short of getting my game compiling and running under a licensed development environment, and it sounds like there are a couple of ways to do this.

I am going to try just sending a mem card and if that doesn't work I will convert to PSPLINK environment (been meaning to do that anyway) and try that.

Thanks to everyone who responded. I'll be sure to update this thread when I have sucess getting a publisher to run my game with a debug box.

Post by **TyRaNiD** » Wed May 17, 2006 5:30 am

Well I would expect unless they have a 1.0/1.5 psp kicking around they will not be able to load anything off a memory stick the protection of where modules can be loaded is part of the IO driver and I would probably suspect that the ms is locked down on a devkit just like a normal PSP. Although the devkit's loader might sit in kernel like psplink so it does matter.

You will also not be able to load anything from flash so that puts things like atrac3 or net out, devs will be able to load stuff like that from host or umd emulation I would suspect but who knows what file system they use and you probably dont want to tell them to copy in such and such a file to make it work.

psplink is probably the closest we have to the way a devkit would work (though a devkit is no doubt better ;P) Still most of this is pure speculation, based on what ive seen of the ps2 tool kit before now.

Gary13579 · Post by **Gary13579** » Wed May 17, 2006 6:01 am

PlayfulPuppy wrote:You don't have to bother with the memory sticks, the dev units can load data off a remote host.

Just get rid of the KXploit and you should be able to just email it to them (Although turning up with it burnt onto a CD would probably be more professional. ;))

edit: Oh, and as far as I know you'll need either an ELF or a PRX, NOT a PBP.

A PBP file (at least the data.psp in it) is a stripped ELF. If they can run ELF's, surely they can run PBP's..

If they are interested in seeing it, then they most likely can load it somehow. I'd include a non-stripped ELF, a PRX, and a PBP (1.0 style) just to ensure they have a method to try it.

dot_blank · Post by **dot_blank** » Wed May 17, 2006 6:56 am

PBP cannot be loaded nonwhatsoever
the devunits do not know about pbp loading
and pbps are done on sony side so best bet
is to stick to good ol' elf/prx as those work fine
also you would do best to not have such magic
keywords in your elf like ms0:/ and lsfatms0:/

as another user has suggested creating a simple
and cheap cd-r burned copy of your elfs would
be another simple option ...but just make sure to
use host0:/ and not ms0:/ as dvd drive is not ms0:/ :P

Gary13579 · Post by **Gary13579** » Thu May 18, 2006 5:57 am

dot_blank wrote:PBP cannot be loaded nonwhatsoever
the devunits do not know about pbp loading
and pbps are done on sony side so best bet
is to stick to good ol' elf/prx as those work fine
also you would do best to not have such magic
keywords in your elf like ms0:/ and lsfatms0:/

as another user has suggested creating a simple
and cheap cd-r burned copy of your elfs would
be another simple option ...but just make sure to
use host0:/ and not ms0:/ as dvd drive is not ms0:/ :P

Well I hope a dev studio would know how to get an ELF out of a PBP...

CyberBill · Post by **CyberBill** » Thu May 18, 2006 4:11 pm

You arnt able to burn a CD or a DVD of the files... The files have to be generated using an internal tool that packages the files into the correct format that the testkit or devkit can use.

As previously stated, sending them a memstick isnt advisable because unless they have a 1.0 or 1.5 retail PSP around, they wont be able to use it because you cant load unsigned executables off of devkit... People are sort of incorrect in stating that the PSP devkits can load unsigned executables from anywhere. Retail PSPs load unsigned executables, but only from UMD. PSP Devkits load unsigned executables, but only from UMD, DVD, and 'remotely'.

If you replace all of your ms0: calls with host0: (remote) or disc0: calls, thats a good start, but you'll also need to add code that initializes and waits for the UMD/DVD to spin up (if you use host0: you dont need to do this). Not hard, but its tricky to test it without a devkit. Also youd need to zip up all of your external files and hope that they have someone working there who knows how to set up the devkit properly to load the files from the correct directories. (Trickier than it sounds)

Basically... you're screwed :P I am assuming that you're trying to get a programming position using your homebrew game as a portfolio, which is totally fine, but if you want to show it off I suggest that you tell them youd love to have them invite you in for an interview.

CyberBill · Post by **CyberBill** » Thu May 18, 2006 4:12 pm

Gary13579 wrote:
dot_blank wrote:PBP cannot be loaded nonwhatsoever
the devunits do not know about pbp loading
and pbps are done on sony side so best bet
is to stick to good ol' elf/prx as those work fine
also you would do best to not have such magic
keywords in your elf like ms0:/ and lsfatms0:/

as another user has suggested creating a simple
and cheap cd-r burned copy of your elfs would
be another simple option ...but just make sure to
use host0:/ and not ms0:/ as dvd drive is not ms0:/ :P
Well I hope a dev studio would know how to get an ELF out of a PBP...

Devlopers never have any interaction with a PBP. All executables are in .elf or .prx format when burnt onto DVD.