forums.ps2dev.org

n1ckn4m3 · Joined: 22 May 2005 Posts: 16

OK guys -- don't flame -- I'm not a developer, just had a couple of ideas here:

Would it not be possible to have a secondary bios chip that was switched -- ie, you hit a switch to enable/disable access to it?

This would allow for the chip to be flashed with the 1.0 bios and leave users with the option of keeping their standard bios upgraded for games purposes, but having the 1.0j bios still safely locked away on a chip.

The biggest problem I see is that in order to get the 1.0j bios flashed onto a new chip, would it not have to be decrypted? And if we could decrypt the bios, I'm sure we would negate the necessity of having the 1.0j bios in the first place?

Of course, with the PSP case being so small, I'm not exactly sure WHERE in the case it would go ....

Just an idea -- if it wouldn't work, don't flame, just discuss.

EDIT: After careful researching and consideration, I have noticed that this type of speculation seems frowned upon here, as similar posts have made it into the hall of shame. If this is the case, mods, please delete this post and accept my humble apology.
_________________
... anyone up for some l33th4x?

;)

F9zDark · Joined: 02 Apr 2005 Posts: 127

I do not think it is possible, because first off, modification to the current bios would need to be in place to make it even acknowledge the second one. Kinda like Gigabyte's Dual Bios for motherboards.

Now if both chips were rigged on a switch which only one chip could be turned on at one time, that may be possible, but like you mentioned, where would it go?

The easiest way to pick up 1.0jp Bios is to buy a japanese PSP and take the bios out. But if you're gonna buy one anyway, might as well devote that one to dev work and homebrew rather than rip apart a good, working PSP to mod another good, working PSP and run the risk of ending up with 2 dead PSPs.

Shikyo · Joined: 22 May 2005 Posts: 2

Um your pretty much just talking about a modchip here. It will happen eventually and I doubt itll be fun to install.

chaos · Joined: 10 Apr 2005 Posts: 135

i'm really hoping the solution for 1.5 will not come down to modchips.. it'd really limit my desire to develope on the psp, because only a select few would be able to run my software.
_________________
Chaosmachine Studios: High Quality Homebrew.

n1ckn4m3 · Joined: 22 May 2005 Posts: 16

Shikyo--
Yes and no... A modchip usually utilizes a secondary bios that has been hacked / created for the soul purpose of allowing homebrew games (and etc.) the ability to run. The only difference here is that it would be to allow the original 1.0j bios instead of a hacked bios. My differentiation is due to the fact that hacked bioses are used to specifically allow 'backup' copies of games to run -- as I understand it, the 1.0j bios does not allow commercial games off of the memstick. This is GOOD. I'm not a fan of game piracy and do not condone the activity -- but I am a fan of homebrew development, having been in the scene for a long time.

The reason this is on topic for me is that I have a lot of experience in programming EEPROMs. 20 years ago I founded a company and created an EEPROM programmer *from scratch* from the bottom to the top. I made the board, the programming (in assembly) to program the EEPROMs, as well as an EEPROM emulator board for the Apple IIe in order to emulate the eeprom before I wrote it so as to test my code prior to actually putting it on a chip... However, this was 20 years ago and the assembly/er code for 68000 series processors is my forte -- not MIPs or x86...

Anyways... I agree with chaos and hope it doesn't come down to a forced mod install. I was only interested because I want to work on getting myself the 1.0j bios on a secondary chip so that I can switch between the two, and wanted to see if anyone had any specific hiccups I'd probably encounter along the way.

Thanks!
_________________
... anyone up for some l33th4x?

;)

digihoe · Joined: 14 May 2005 Posts: 108

One little hickup... BGA soldering/rework such equipment are not cheap to come by or easy to use... In order to get this to work you would have to fit a PCB somewhere too (and the PSP is kind of limited when it comes to space)...

Best regards!

EdZ · Joined: 24 Apr 2005 Posts: 28

BGA? I'm sure you mean surface mount, right?

::EDIT:: Sorry about that. I was thinking of LGA, not BGA.

inomine · Joined: 05 May 2005 Posts: 53

No, he means BGA which is a type of SMD. Have a look here http://en.wikipedia.org/wiki/Ball_grid_array for some more details.

Vyrus001 · Joined: 26 Apr 2005 Posts: 30

well the other MAJOR pro to the makeing of a mod chip is the fact that we could use it to crack the crypto on the regular bios...

i.e. if sombody manages to make a "mod chiP" for the psp, then one could write software to monitor and control the update (1.5) running and through the anlalyzation of it's rutines could figure out just what the heck that thing does to make it only run crypted elfs. meaning we could then make our own crypted elfs and whala... no more mod chips nessisary :P

Guest · Posted: Mon May 23, 2005 5:56 pm Post subject:

Modchip development talk is very much against the rules of the forums. I know its late to lock this thread but better late than never.

Please do not discuss developing modchips for the PSP in these forums.
Oh and please check out the rules again in the "Announcements" forum. I know I needed a refresher...