PS1/2 Intoducing PsNee - An open source stealth modchip for the PSX

[garyopa]

Back in 2015 @marvin96 started a project called PsNee on AssemblerGames

But the website was down for several months in 2017, but during that downtime the developers didn't give up and moved their project to psxdev.net, and now there is also a PsNee Project at GitHub. And @modrobert whom has been following the project on his website EurAsia reports there has been a lot of progress and this impressive open source modchip is now working stable according to several reports.

The source code is multi-region, meaning it will unlock PAL, NTSC-U and NTSC-J machines, handles antimod games while remaining stealth, it supports Arduino ATmega based boards and ATtiny MCU.

For those interested in the in-depth technical details I suggest taking a look at the Arduino source code. There are plenty of comments explaining the different patch stages for disc auth and how the BIOS patching is done to support NTSC 60Hz video signal on PAL PM-41 boards (PSone).

The BIOS patch is waiting for address line 18 to go high, then it patches by holding data line d2 low. A clever minimalistic solution which means less intrusive mod with less wires.

As @modrobert points out this what makes open-source projects so much fun, and it breaths new live into our old Classic Sony PlayStation consoles which are now favorites among the growing retro gamers some of whom have never played before on PSX system, and since games are hard to get this opens up using cough 'backups' for them.

Project Home: PsNee
Source #1: EurAsia
Source #2: MaxConsole