PS3 Question about PS3 PS2 classics configs

[depaul]

Hello everyone.
I'm trying to understand how config files work for PS3 PS2 classics? how a simple 64 bytes file can make a PS2 game magically work?

Do these configs generally disable some functionalities (caching, rendering...) to make games work?

Do configs use MIPS instructions? some specific version?

Do these instructions deal with DVD data offsets (byte offset), or LBA address? or...?

Is there any link for more information please? sorry I am complete noob.

Thanks

 

[aldostools]

Hello everyone.
I'm trying to understand how config files work for PS3 PS2 classics? how a simple 64 bytes file can make a PS2 game magically work?

Do these configs generally disable some functionalities (caching, rendering...) to make games work?

Do configs use MIPS instructions? some specific version?

Do these instructions deal with DVD data offsets (byte offset), or LBA address? or...?

Is there any link for more information please? sorry I am complete noob.

Thanks

The CONFIG is an external configuration file used to modify the behavior of some internal features of the PS2 emulator. There are different commands to perform different tasks, like enable pressure sensitive controls, patch EE memory, patch game disc by sector & offset, etc. Some commands use opcodes of MIPS instructions to disable features, change MIPS registers, etc.

The PS2 emulator used by PS3 is based on PCSX2. So most of the patches can be ported from a system to another. However there is not much information or tutorials about the process. Indeed not all the commands documented and some have an unclear purpose.

These configs are not magic. They require a lot of time and effort to fix a game using these small files. Each game require a different strategy to improve performance, visuals or avoid freeze/black screens during gameplay. Generally disabling some effects like fog, shadows, reflection, etc. help to improve the performance or fix glitches, at the cost of reduced visual graphics.

These are some useful links:
https://www.psdevwiki.com/ps3/PS2_Emulation#Game_CONFIG
https://github.com/aldostools/webMAN-MOD/blob/master/_Projects_/updater/PS2CONFIG/README.md

https://ps3.aldostools.org/ps2config.html
https://www.psx-place.com/threads/compatibility-list-ps2-on-ps3.1306/

Most of the custom CONFIG files in the database were made @kozarovv, @mrjaredbeta, @Agrippa. But there are also official configs extracted from gx & soft ps2 emulators or obtained from official PS2 games released on the PSN store.

 

[depaul]

The CONFIG is an external configuration file used to modify the behavior of some internal features of the PS2 emulator. There are different commands to perform different tasks, like enable pressure sensitive controls, patch EE memory, patch game disc by sector & offset, etc. Some commands use opcodes of MIPS instructions to disable features, change MIPS registers, etc.

The PS2 emulator used by PS3 is based on PCSX2. So most of the patches can be ported from a system to another. However there is not much information or tutorials about the process. Indeed not all the commands documented and some have an unclear purpose.

These configs are not magic. They require a lot of time and effort to fix a game using these small files. Each game require a different strategy to improve performance, visuals or avoid freeze/black screens during gameplay. Generally disabling some effects like fog, shadows, reflection, etc. help to improve the performance or fix glitches, at the cost of reduced visual graphics.

These are some useful links:
https://www.psdevwiki.com/ps3/PS2_Emulation#Game_CONFIG
https://github.com/aldostools/webMAN-MOD/blob/master/_Projects_/updater/PS2CONFIG/README.md

https://ps3.aldostools.org/ps2config.html
https://www.psx-place.com/threads/compatibility-list-ps2-on-ps3.1306/

Most of the custom CONFIG files in the database were made @kozarovv, @mrjaredbeta, @Agrippa. But there are also official configs extracted from gx & soft ps2 emulators or obtained from official PS2 games released on the PSN store.

Thank you very much Chief. Will make sure to check those links
As I thought, so making those Configs is hard indeed, and requires a lot of knowledge. Thanks to all members that helped create configs database

 

[mrjaredbeta]

Yup, @aldostools answered it exactly right. The dev wiki page will help tremendously if you are interested in learning about the different config commands and how they work.

Most configs manipulate MIPS code in EE memory (command 0x0A), similar to how PCSX2 pnach files work. But yeah, pretty much everything else you mentioned is doable: patches to disc image on-the-fly (command 0x0B), changes to caching (command 0x03 and 0x21), and also other settings like math accuracy adjustments (command 0x0F/0x10), custom hooks Sony made for specific games/engines to circumvent issues (command 0x01), stuff like that. Most commands were brought over from gxemu, but netemu introduced several new commands (mostly related to the new GS emulation).

These config pages are good if you're interested in what some do for specific games:

https://www.psdevwiki.com/ps3/PS2_Custom_Configs
https://www.psdevwiki.com/ps3/PS2_Official_Configs

It's really fun dealing with them, and it makes me happy to know that it helps people enjoy their favorite games again.

 

[depaul]

Yup, @aldostools answered it exactly right. The dev wiki page will help tremendously if you are interested in learning about the different config commands and how they work.

Most configs manipulate MIPS code in EE memory (command 0x0A), similar to how PCSX2 pnach files work. But yeah, pretty much everything else you mentioned is doable: patches to disc image on-the-fly (command 0x0B), changes to caching (command 0x03 and 0x21), and also other settings like math accuracy adjustments (command 0x0F/0x10), custom hooks Sony made for specific games/engines to circumvent issues (command 0x01), stuff like that. Most commands were brought over from gxemu, but netemu introduced several new commands (mostly related to the new GS emulation).

These config pages are good if you're interested in what some do for specific games:

https://www.psdevwiki.com/ps3/PS2_Custom_Configs
https://www.psdevwiki.com/ps3/PS2_Official_Configs

It's really fun dealing with them, and it makes me happy to know that it helps people enjoy their favorite games again.

Thank you very much for helping everyone here, Mr @mrjaredbeta