Modding My PS1

[SMurphy]

Hello. I'm a collector of classic consoles and although I still have the PS1 I got... 18 or 20 years ago... that can't be right... feeling old now . Anyway, I recently spotted a Japanese SCPH-1000 on ebay so threw in a bid and won it.

Unfortunately it was last minute and was not until I received it I noticed there was no S-Video port. Guessing the motherboard has been changed at some point as it's a SCPH-1000 case with a PU-8 board in it. But as an added bonus it's already chipped and has a board with the correct bits for dual oscillators.

So my plan is to take the oscillator out of my PAL console and put in the PU-8 one along with the NTSC oscillator. So that should give me a console that can play any game quite happily, and if what I remember form a long long time ago I wont need any other mods to fix colours and stuff.
EDIT 2: I really should have read through all the posts first. This is exatly what I was looking for http://www.psxdev.net/forum/viewtopic.php?f=47&t=628

As for the mod chip, I may be getting confused with the PS2 but I'm sure there were games that could tell if you had a chip. But then there were chips that could hide themselves, and if that’s right then I'll need help identifying what chip is fitted. So far all I can say is it's a 4 wire one.

Now for the mods I want to do but have no idea about.

The BIOS is probably going to be a Japanese one, and from what I remember the old consoles were missing some stuff in the BIOS to do with playing CD's or something. So, I would like to just swap the BIOS from my newer PAL console into the older one, but would this work and is there any benefit of keeping both and switching between them?
EDIT: Found a nice post about setting up dual BIOS http://www.psxdev.net/forum/viewtopic.p ... =602#p4635 Still not sure if it's worth while having two or just using the newest one.

Also, the CD lens is in a different place on the older console to my newer one. Is there any benefit to where the lens is or the type of lens fitted? Is it worth while using the casing from my newer console and the newer laser?

Over the next week or two I want to get stuck in making all these mods, so will update this topic with what I get done and pictures for others to possibly get some help from. Though I'm gonna need some help myself, spent so many years modding 360's I've forgot what a decent made console looks like .

P.S. If therse are any other mods that are worth doing let me know. I'd like to get everything done at once so I can just enjoy gaming .

[SMurphy]

So I gave the consoles a quick once over today. Here are the pics;


As you can see I had a thing for Cheetos when I was younger. Think that explains my belly these days. Though I do have a guitar strap covered in beer bottle caps...


So my original console is SCPH-7502.


It has a PU-22 motherboard, but not much else to see thanks to the shielding soldered onto it.


Even less to see on the bottom.


Model sticker on the console I just got off ebay.


Here is the back of the Japanese SCPH-1000 console missing the S-Video port.


Someone didn't like having a spring in place so decided to fit a switch to keep the cd "tray" closed.


No covering up for the PU-8 motherboard, the little dirty has it all on show.


A but more interesting on the under side to.


Decent quality switch with some nice resin covering the contacts. No expence spared or hot snot here .


The mod chip. Generic wee PIC so guess it wont have the "safe" feature to hide itself.


Oscillator with a nice unpopulated space beside it. Just need to check it's not a PAL board they have fitted.


Hmm, some caps just can't handle their voltage. Someone has put 230v into this 110v PSU.

So there is where I am so far.

I'm going to bring home the Japanese console tomorrow and fit the PSU out of Cheetos to see if it works. If it does then I'll see if the mod chip can boot some games that don't like mod chips. Will bring my soldering station home as well and get the shielding off the Cheetos motherboard to see what I;m working with. No idea if the BIOS chips will be the same or if the oscillator will be a new style. PU-22 is a long way form PU-8...

[SMurphy]

So last night decided to pop the PSU out of my "Cheetos" PS1, into the Japanese one and see if it works.



Not even started and we have a problem. The old PSU has a 7 wire cable and the new one only has 5 wires.

A quick Google and we have a pinout of the two cables;

So, we just need to remove the orange 3.5v and red ground wires, then move the brown 8v wire up.


There we go, but it's still a 7 pin plug and only a 5 pin socket on the PSU.


So I removed the 5 pin plastic socket and put the 7 pin plastic socket on. I didn't desolder the pins, just swapped the plastic sockets.


I've completely removed the extra wires from the cable, just need to check if we need to do anything to the motherboard socket.


Looking at the tracks on the motherboard, we don’t need to worry about the missing ground as all three are well tied together. However after checking continuity the 3.5v pins are going to need connected.


A little jumper wire sorts that out. It may have been quicker to cut up the two cables and make a hybrid one, but this way of modding means everything can be un-modded beautifully.

Now just to put it together and plug it in .


IT'S ALIVE!!!


AND IT SPEAKS ENGLISH!!??

Yeah, after looking at the oscillator again and checking the number, this is a PAL board . So, since I have 2 PAL consoles I'll not be able to setup my dual oscillators.

This board does have the extra outputs and a mod chip so may be worth keeping hold of. Going to dig out my old PS1 games and see if the laser works and how the chip works.

[Administrator]

The old PSX's (IE: SCPH-1000) consume more power than the newer ones (IE: 5502), so the newer PSX PSU may run slightly warmer. That's also why they have dual 3.5V rails from the PSU, as it was for handling more current.

[SMurphy]

The old PSX's (IE: SCPH-1000) consume more power than the newer ones (IE: 5502), so the newer PSX PSU may run slightly warmer. That's also why they have dual 3.5V rails from the PSU, as it was for handling more current.

I didn't actually think about that. Rookie mistake there . Newer PSU managed to power it and run a couple of game for a while. Probably not the best permanent solution though.

Anyway, I've unmodded the cable and put the original PSU back in and build the console up again. Since it's PAL it's not really of much use to me, so going to throw it back on ebay and stick with my Cheetos one for now. Hopefully get some money to put towards modding Cheetos or a PSIO when they are ready again .

[LordHexahedron]

12C508*... that's an MM3 stealth chip [well, it should be - I can't guarantee it 100% without popping it in my EEPROM programmer and dumping the image], it'll work with even modchip aware games (unless there are other chips that use the same PIC, but 4 wire 12C508 sounds like MM3 to me).


*yes, that's a 12C509 for the astute reader - however the chips are functionally identical and interchangeable - there are some minor technical differences but they don't matter for modchips.

[tripod731]

Hi, guys!
How can I see pictures you provided in topic?

[Administrator]

Try using the Internet Archive site.

[chip127]

So last night decided to pop the PSU out of my "Cheetos" PS1, into the Japanese one and see if it works.



Not even started and we have a problem. The old PSU has a 7 wire cable and the new one only has 5 wires.

A quick Google and we have a pinout of the two cables;

So, we just need to remove the orange 3.5v and red ground wires, then move the brown 8v wire up.


There we go, but it's still a 7 pin plug and only a 5 pin socket on the PSU.


So I removed the 5 pin plastic socket and put the 7 pin plastic socket on. I didn't desolder the pins, just swapped the plastic sockets.


I've completely removed the extra wires from the cable, just need to check if we need to do anything to the motherboard socket.


Looking at the tracks on the motherboard, we don’t need to worry about the missing ground as all three are well tied together. However after checking continuity the 3.5v pins are going to need connected.


A little jumper wire sorts that out. It may have been quicker to cut up the two cables and make a hybrid one, but this way of modding means everything can be un-modded beautifully.

Now just to put it together and plug it in .


IT'S ALIVE!!!


AND IT SPEAKS ENGLISH!!??

Yeah, after looking at the oscillator again and checking the number, this is a PAL board . So, since I have 2 PAL consoles I'll not be able to setup my dual oscillators.

This board does have the extra outputs and a mod chip so may be worth keeping hold of. Going to dig out my old PS1 games and see if the laser works and how the chip works.

pictures do not work .. Please reboot. Please !!!

[Administrator]

Try sending the OP a message directly since the images were hosted on their server.