pcsx-redux VS unirom8_bootdisc_and_firmware_for_ps1

PSn00bSDK maintainer here. Unfortunately the project cannot really be considered clean room; the original versions of most libraries contained code that was either lifted straight from Psy-Q disassemblies or heavily inspired by them. I have since rewritten pretty much all of it (with the exception of the GTE library which still has some Sony code) using only Psy-Q API documentation as a reference, but the "ship of Theseus" nature of the rewrite makes it hard to argue that it is a clean and legally safe project.

On the flip side, there are plenty of other open source PS1 SDK options that have been written from scratch, do not reimplement the same API as Psy-Q and can thus be considered clean for the most part. Here's a few of them:

- https://github.com/grumpycoders/pcsx-redux/tree/main/src/mip...

- https://github.com/ChenThread/candyk-psx

- https://github.com/cuckydev/CKSDK

- https://github.com/spicyjpeg/ps1-bare-metal (shameless plug)

Sony must license that out as well (or a non-Sony FOSS BIOS like OpenBIOS is used) as even on Steam there are a handful of emulated PS1 titles, I'm sure there are games on non-Sony consoles that use PS1 emulation as well but I'd have to research to find some.

That's just a reality of PS1 emulation, you need a BIOS. Duckstation is actually one of the easiest emulators to set up and still my #1 recommendation for PS1. If you don't want to set up a BIOS, you could try PCSX-Redux which has a simulated BIOS built in.

You can also use https://github.com/grumpycoders/pcsx-redux/tree/main/src/mips/psyqo

try here: https://github.com/grumpycoders/pcsx-redux

The PSX OpenBios is still a work in progress, but it already boots a great part of the console's library. Check it out!

There are homebrew tools that can be installed on a PS1 memory card [1] and allow for executables to be loaded from a host machine into RAM through the serial port on the back of the console, in a similar way to what Sony's official Net Yaroze loader did back in the day. These tools can also use undocumented CD-ROM drive commands to disable region checks without the need for a modchip, provide semihosting (host filesystem access) and so on.

On the PS2 it's slightly more complicated, as there is no way to launch the "native" PS1 backwards compatibility mode other than to use a modchip (or firmware mod on some models) and burn the executable onto a disc; the serial port is not exposed either, making debugging much harder. It can still be done, but it's much easier to just use an actual PS1.

[1]: https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmw...

I just tried it myself, using an unmodded SCPH-9001, and original CD (Tomb Raider II, NTSC:U/C to be precise) and a burned copy of the Unirom 8.0K installer disc (from https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmware_for_ps1/releases/), and it booted without problems.

FreePSXBoot: https://github.com/brad-lin/FreePSXBoot Unirom: https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmware_for_ps1 TonyHax: https://github.com/socram8888/tonyhax

Burn a CD with the latest unirom CD: https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmware_for_ps1

Yes. An alternative would be to swap trick with original game and the UNIROM burned disc. You can download it from its GitHub page. https://github.com/JonathanDotCel/unirom8_bootdisc_and_firmware_for_ps1

- Unirom also has a memory card manager that let's you see and undelete saves. You need either a CD-R with Unirom burned to it (on a modchipped PS or with a swap trick), or a memory card with FreePSXBoot using Unirom (on any non-chipped PS).