PS3 Compatibility List - PS2 on PS3

EE and VU0 are emulated on the PPE not SPE. Therefore, a special SPE float rounding mode for VMX/AltiVec is activated through the HV call for the PS2 emulation purposes. Everything is written on the wiki page, especially there.
We don't know where VU0 is emulated actually, we know the EEs main core (R5900) is emulated on the PPU and VU1 on an SPU (at least in gxemu and softemu). Netemu we don't know. Also the article stated that "PS3 models without Emotion Engine unit use "SPE-compatible SIMD graphics-rounding mode for VMX/Altivec Instructions" for FPU, and VU0 emulated floats calculations. This is set on emulator init by HV call 97 with param 1. VU1 actually run at SPE core so no compatibility mode need (or can) to be set. SPE compatible mode for PPE mean that rounding mode is set as round to zero, denormals are treated as zero, and there are no infinities or NaNs. So theoretically what PS2 FPU/VU was originally. Although SPE and PPE SPE compatibility mode is still inaccurate comparing to PS2, because Sony decided to cut off 2 guard bits from calculations on PS2. Probably because there was no need for round and sticky bits (no Nan/Inf, one round mode, etc.). Additionally float divide algorithm is custom and not fully understood up to this day. Good example here are TriAce games, or Castlevania COD where SPE calculation is wrong by 1 bit making games unplayable without patch. This are PS2 math algo specific inaccuracies in FPU/VU implementation that are not present on any other hardware."
So basically floats always run an SPU but it's still not accurate to real PS2 hardware because the real EE is missing 2 guard bits for rounding.
 
EE and VU0 run on the PPE because of the synchronization requirements. The quote you posted from the wiki does confirm that. Actually, both R5900 and VU0 recompilers and PPC emitter functions are reversed and documented by the one and only Mr. K.
 
Oh that's how it's meant with the VMX compatible mode but "EE and VU0" still sounds weird since the EE contains both VUs.

It also still explains why float emulation on the PS3 is not correct enough for emulation compatibility. I.E. why games still break.
 
King's Field: The Ancient City (SLUS-20318)
Code:
3D 00 00 00 57 44 00 00 10 00 00 00 00 0D 1C 00
00 0D 1C 00 10 00 00 00 0C 0D 1C 00 0C 0D 1C 00
0E 00 00 00 2C 0D 1C 00
Fixes black voids where doors are supposed to be. This basically sets accurate instructions on only the ones that need it (two mul.s and one add.s).

@Lucidz13 This may or may not fix other doors in the game (if they have this issue). It also may affect frame rate a slight bit as soft floats on mul.s are intensive. This particular config did not affect frame rate in my testing around the save file.
 

Attachments

@mrjaredbeta
is there a special way to make config files work with managunz? im just putting it in the same PS2ISO folder as kf4 and its not doing anything for me. theres just one door in my save that is having the loading problem. i could give you directions to it from my most recent save if you want. theres another door that has the same problem when i tried to go through from a certain area but i had already been through it before by coming from a different direction so it didnt seem like that bad of bug until i saw the most recent one
 
Last edited:
You have to rename it exactly as your ISO, such as: King's Field IV - The Ancient City.iso.CONFIG

I have this tested and working on the door at the very top of the stairwells on the second save as that is the door that I found was bugged. Kozarovv pointed out to me a better method of the config anyways, so I will be posting new configs for every region soon.
 
@mrjaredbeta holy pog thanks a ton man! this game is so good the music and atmosphere are so surreal and incredible i probably would have bought a copy or tried to hard mod my ps2 or something just to finish my playthrough lol
 
King's Field: The Ancient City (SLUS-20318)
Code:
3D 00 00 00 57 44 00 00 0A 00 00 00 01 00 00 00
2C E4 1B 00 34 00 15 46 36 00 15 46 0E 00 00 00
2C 0D 1C 00

King's Field IV (SLES-50920)
Code:
3D 00 00 00 57 44 00 00 0A 00 00 00 01 00 00 00
4C CC 1B 00 34 00 15 46 36 00 15 46 0E 00 00 00
4C F5 1B 00
Alternative config with Wgarvin's PCSX2 patch in place of the mul.s instruction accuracy improvement. As pointed out by kozarovv, PCSX2's add/sub is always accurate, so PCSX2 only needs memory patch to change float conditional instead of messing with how its mul accuracy works. In turn, netemu requires both the PCSX2 patch as well as the single add.s instruction accuracy improvement in order for the door to show properly.

NTSC-J config coming at...some point. :)
 
hi, i just found in tales of rebirth some minor sounds issues when you enter in certain areas and dungeons a pitch weird sound keep and they goes away after a while, reset or enter on another area, also game over screen should hear a voice whith the classic ''and they never hear from them again'' but they dont and only music they sound
 

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