PsNee: a stealth modchip for all PS1-models

Finally! Progress!
It's been a while I admit, I really didn't find the time to work on this project last month(s).
Anyways, I've burned the OneChip hex on a 12F508 and bodged it on the dev SCPH-102 (lots of wires sticking out); NTSC games suddenly booted!
I've captured a PAL original, PAL backup and NTSC backup with the Saleae logic analyzer with and without the OneChip. You can find the captures here. The files can be opened with Logic from Saleae (free) and are created with version 1.0.33.
Now I just have to figure out what OneChip does that PsNee doesn't to let those NTSC games play. That's the hard part. Perhaps @TriMesh has got an idea now? ;-)

 

I thought the OneChip connected to the BIOS and/or some other signals and patched the region check done via software in the PAL BIOS?

 

Yes, that's what basically the 2 wires connected to the bios does.

He wants to know the timing etc to reimplement it

 

I've learned some assembly in the mean time, it is more effective to interpret the disassembled OneChip hex than to look hours at logic analyzer shots. I'm lucky that the 12C508 only has 0.75kB flash. ;-) A step-by-step debugger also helps me to verify my thoughts.
It's going quite well, I've already figured out a lot of the delay times OneChip uses and when it patches the BIOS D2 line. Next weeks will be quite busy so I don't know if I've got time to work a lot on it, but things are looking good.

OneChip functions just like an ordinary PAL mochip, except it -at some point- forces the BIOS D2 line to 0 to bypass the NTSC check of the SCPH-102 Playstations.

 

Just found this project, and totally love the idea. I was searching the web, figuring someone had to have made a modchip from an ATTiny, and sure enough! Just ordered some ATTiny45's, going to tryPsNee V1 on my 55XX, hopefully right after x-mas. Thanks so much!

 

Awesome to hear man! It's been a busy week, there hasn't been much progress for the next version of PsNee. However... I've got some days to spare around NYE, so maybe, just maybe a new version will be released before 2016.
Developing the modchip takes a lot of time consuming testing, whick is why progress has been a bit slow lately.

 

Take your time and if you need some help with testing I can help you.

 

Yeah, I've installed mine with a dip8 socket, so if you need someone to test anything on a 55XX, let me know, happy to help!

 

Just wanted to chime in and say I am following this project. Really appreciate the hard work put into it thus far.

 

Does this work on NTSC consoles as well? Never owned a PSX before yesterday, so forgive my dumb question. My precise model is SCPH-550.
http://i.imgur.com/oMSSaJH.jpg

if you aren't sure, I have a spare ATMega328p I can test with it for you.

I think I can figure it out from the program, but I'm wondering what the un-numbered red orange white and blue dots are marking on the 5xxx photo.

 

I edited existing diagrams hence why there is unmarked points.

There have been issues with V2 so your mileage may vary.

 

ALL RIGHT GUYS, I'M BAAAAAAAAAAAAAAAAAAACK!
I know it's been some time, but I've been extremely busy. HOWEVER, yesterday I had some time to spare, so why not on PsNee?
And you know what? After some more tweaking of the V5 I left at in February, PsNee V6 now works extremely well!
I've restructured the code, vastly improved the PAL-NTSC BIOS patch and well... made the modchip work on all discs So backup or original, PAL or NTSC, it doesn't matter anymore.
And, this is all without the gate nor the /xlat signals The code has been tested with numerous games on a PAL SCPH-102 and functions perfectly.
The attached code only spews PAL validity codes but it can very easily be modified for other regions (or all three), all the required functions are already written for you.
Wiring also is fixed, so no more hassle on that front. Mind that the wiring is different to the former versions of PsNee.

Let me know what you think! Enjoy!

 

Awesome! I'll have to give it a test later on.

Is it possible to get one already made for NTSC-U & NTSC-J regions... assuming this works on more than just SCPH-102.

Edit: that video, wtf?

 

The code is very easily edited to your own likings, just replace inject_SCEE() with inject_SCEA() in inject_playstation() for NTSC-U consoles. I haven't tested the code on other models, it may be that you need to comment out the NTSC-PAL BIOS patch and replace it with a 3000ms delay, but it may also work just fine the way it is now.

 

Does PsNee bypass the territory protection on NTSC-J models?

 

Greetings all, I have the following consoles:

SCPH-102 (mini PSOne)
SCPH-1001 (first gen with RCA ports)
SCPH-5000 (japanese model)

If I were to buy Atmel ATTINY45-20PU my understanding is I could use it in the 102 and the 5000 but not the 1001? Obviously after programming with Ps Nee.

 

I have a question:

Does PsNee change the BIOS video mode to NTSC (PAL60 on PAL consoles) during initial startup,just like OneChip did?

I had a PSone I bought with a OneChip fitted,and this would be the exact behaviour - every time I'd boot up the console,it would output PAL60 during the startup Sony diamond,and would switch to the desired video mode according to the disc. (NTSC discs would retain the PAL60 mode and PAL discs would just go into normal PAL mode)

 

It will behave the same as the old OneChip (since it does the same trick to bypass the BIOS protection).

 

I am confused to which PSOne SCPH-102 PAL - PM 41 (A) pins I connect using a ATTiny45;

From PsNeeV6.ino

// Pinouts
// data = ATTiny pin 5
// gate = ATTiny pin 6
// lid = ATTiny pin 7
// biosA18 = ATTiny pin 2 = Address18 (BIOS pin 31)
// biosD2 = ATTiny pin 3 = Data2 (BIOS pin 15)

Are BIOS pins 31 and 15 the correct pins make connection to?

 

That isnt the bios