Topic: FB Alpha 0.2.97.43 Bug Reports

[dink]

The raspberry 3 should be fine with those speedhacks disabled, i'm wondering about older/slower devices though. I'll make some test and let you know by pm the results.

Excellent, yea, it would be nice to remove them or at least give an option.  The thing is, people have been raving about our neogeo support for years, and I really hope disabling this speedhack doesn't uncover anything more serious or cause problems down the line.  Would you try some previously problematic games, like s1945p, and see if there is any regression with the speedhack off?

thanks,
- dink

[barbudreadmon]

I'm observing a ~2% performance decrease without the speedhack (i underclocked my rpi3, checked the fps with and without the speedhack, it went from ~50 to ~49 fps), and s1945p is running fine when i'm back at normal clock, i don't think this speedhack is worth keeping.

[jan_klaassen]

IIRC the speed hack was put in for s1945p specifically. in the stone age when cpu speed was still measured in MHz. (That game talks to the sound cpu differently from other neo geo games, and requires the emulation to switch back and forth between the emulated cpus a lot).

[barbudreadmon]

Actually, with or without the speedhack, karnovr doesn't seem to have music in selection screen and ingame when using mvs bios. aes and unibios seems fine though.

[dink]

Actually, with or without the speedhack, karnovr doesn't seem to have music in selection screen and ingame when using mvs bios. aes and unibios seems fine though.

I remember fixing this problem in karnovr, but, I don't know where the fix is.  I checked the entire neogeo svn history and I don't see it.  IIRC it was something to do with irq's getting skipped.  If it comes back to me, I'll say something   but verify: 2610 soundcore & interface, z80 interface and cpu core are all up to date.  It seems like the only thing I can find relating to it is: http://http://neo-source.com/index.php?topic=2879.msg21278#msg21278

best regards,
- dink

[barbudreadmon]

I remember fixing this problem in karnovr, but, I don't know where the fix is.  I checked the entire neogeo svn history and I don't see it.  IIRC it was something to do with irq's getting skipped.  If it comes back to me, I'll say something   but verify: 2610 soundcore & interface, z80 interface and cpu core are all up to date.  It seems like the only thing I can find relating to it is: http://http://neo-source.com/index.php?topic=2879.msg21278#msg21278

best regards,
- dink

Could it be related to those 2 commit ?
https://github.com/libretro/fbalpha/commit/c197019873817680fda27d8e8fbdb9b5e5129e5c
https://github.com/libretro/fbalpha/commit/310d3e2a8d9eb65e2495faae28302f497266ecb2

That's the 2 hotfix you gave me for s1945p in february, Karnov's irq issue was mentioned in the code before the changes.

[dink]

barbudreadmon, ahh yes - now I remember - after properly fixing the Z80's ZetRunEnd() also fixed karnovr (without having to disable ZetRunEnd() of course).  I can confirm karnovr is working in FBA with or without speedhacks using the default dips, though.  I wish I had some helpfull information for you, but, this is a strange one.

best regards,
- dink

[barbudreadmon]

barbudreadmon, ahh yes - now I remember - after properly fixing the Z80's ZetRunEnd() also fixed karnovr (without having to disable ZetRunEnd() of course).  I can confirm karnovr is working in FBA with or without speedhacks using the default dips, though.  I wish I had some helpfull information for you, but, this is a strange one.

best regards,
- dink

Hmm the neogeo driver in lr-fbalpha should be in sync with the one in standalone fbalpha, so perhaps some kind of issue related to the compiler/cflags ? Did you use gcc or msvc for your test ? And if gcc, which version ? I'll also try without the -O3 cflag when i'm back home.

[Treble Winner]

Hmm the neogeo driver in lr-fbalpha should be in sync with the one in standalone fbalpha, so perhaps some kind of issue related to the compiler/cflags ? Did you use gcc or msvc for your test ? And if gcc, which version ? I'll also try without the -O3 cflag when i'm back home.

The ZetRunEnd fix would be in the Z80 Interface/Core though - so external to the driver itself....

[dink]

Hmm the neogeo driver in lr-fbalpha should be in sync with the one in standalone fbalpha, so perhaps some kind of issue related to the compiler/cflags ? Did you use gcc or msvc for your test ? And if gcc, which version ? I'll also try without the -O3 cflag when i'm back home.

I'm using gcc 4.8.1 with -O3 here, I wonder about this :/  do any errors/warnings come up when compiling?  can you try asan-ing it?

[barbudreadmon]

My bad, it seems an old karnovr.fs was at fault here, i should have tried removing it first.

[dink]

No problem, I'm relieved to know it was something simple

best regards,
- dink

[barbudreadmon]

I was wrong, removing karnovr.fs didn't solve this issue, and i think i was finally able to reproduce this issue consistently :

1. start the game (any mvs or unibios arcade)
2. insert coin so that the game go to the title screen
3. wait for title screen music to start, immediately insert coin => music stop
4. process further by pressing start, there is no music

[dink]

barbudreadmon, I can't reproduce that here at all using MVS USA ver.5 2slot, MVS Asia Europe ver.6 2slot, Universe Bios v3.0.  I tried it 10 times for each bios just to make sure.   These tests were made with "#undef USE_SPEEDHACKS".  I also tried twice with Unibios and the default "MVS Asia/Europe ver.6" with the speedhacks enabled, and still no problem.  I'm really not sure what's going on :/

best regards,
- dink

[barbudreadmon]

Weirdest issue ever :
- The guy who reported this get no sound when in non-aes mode, whatever he does
- I get music as long as i don't press coin when the title screen music is running
- You don't have this issue at all.

I'll try to get to the bottom of this, perhaps using different gcc version with various sanitizer will help.

Also, this is the other thing that comes to mind, perhaps it is worth mentioning the audio settings described here are hardcoded in the libretro port.