Poor lr-mess performance with Ti99_4a on Pi3B+

jamrom2

Hi. After working with Folly for the past few months and getting a ton of new systems working with "one-click game start" game playing possibilities on these old computer systems, I thought it was time to ask this question.

I'm running RetroPie on a Pi3b+, latest build 4.7.1 and completely updated as far as I can tell. Setup Script is 4.7.21.

The Ti99_4a is a slidehsow. To compare, the the CoCo 2 & 3 and Apple IIe suffer a little performance degrading, but are definitely very playable.

Is there anything that can be done to help the performance of Ti99_4a lr-mess emulation in the RetroPie environment? Other than using the native emulator (Ti99Sim), which has no "nostalgic" visual options and no "one-click" into playing the game , lr-mess is the only way to enjoy this system with overlays and shaders and no input game start. Even turning off all the visual options is no help.

Thanks

JamR

jamrom2

Sorry... thought this one fit more in the Development area when I posted it.

Thanks! :)

jamrom2

Just noticed it's the same for many of the hand-held games working in lr-mess as well...

DTEAM

@jamrom2 said in Poor lr-mess performance with Ti99_4a on Pi3B+:

Just noticed it's the same for many of the hand-held games working in lr-mess as well...

For handheld games you must use AutoFrameSkip.

jamrom2

@DTEAM I see what you mean for the handhelds. Frameskip +10 works great for Caveman.

I wonder if we should to the same for the Ti99_4a?

Folly

@jamrom2

what is your experience of autoframeskipping vs frameskip 10 with pressing these keys in ti99_4a ? :

F11 => show frames
F9 => increase frameskipping
F8 => decrease frameskipping

I can add it for the non-basename lines if we need to.

jamrom2

@Folly I wonder if it's something that can be fixed this way or the way MAME emulates the Ti99_4a?

I'll try this and let you know in a moment.

jamrom2

@Folly No change of the performance at any setting.

0/10 or 10/10.

Folly

@jamrom2

So there is no need to add frameskip 10 loaders then.

What is your framerate ?
Have you tried to lower your resolution in the startup-gui ?

jamrom2

@Folly How do I display the framrate? I see it via F11 as around 45% if that's it. Usually it's a rolling number right.

Yes, changing resolutions, turning off overlays, shaders.. etc. has no effect.

Folly

@jamrom2

Ok,
Probably you are out of luck and you need to get a RPI4.
I would buy a 8GB version because it can run on 1,8Ghz in default in the new bullseye distribution.

Folly

@jamrom2

Don't you have an old x86 or x86_64 computer lying around ?
I would try it on that.

jamrom2

@Folly No, definitely don't. Lol.

I was wondering if it would be worth asking someone on the Librettro team to have a look at this...or even from MAME. It's odd to me that it's only the Ti99_4a that gets beat-up like this. All the other computers from this era seem to work fine.

I suppose nothing will come out of it, but it's worth a try to ask.

Folly

@jamrom2

It has to be addressed in mame if possible.
After that it will automatically go into the libretro core.

You should make an account here and discuss the problem :
https://forums.bannister.org/ubbthreads.php?ubb=postlist&Board=1

It's troublesome to get your username activated.
You probably need to email to get it activated, just like me.
Then you can search the forum.

I have an account too but I can't post anything so far.

Edit:
I did a search for you but could not find anything useful.

Folly

@jamrom2

Have you tried the slider functions ?
Underclocking or overclocking the cpu ?

Perhaps not ideal but have you ever tried running your RPI3 from CVBS instead of HDMI.
CVBS could improve speed also.

jamrom2

@Folly what is cvbs?

I will try the sliders... I used them on one of the handheld games which seemed to help, but it doesn't save.

I didn't want to have to change the basic build too much to fit one system. I'd rather keep it simple if possible. End result is most likely I buy a Pi4.

It's just bugging me because I know how old the Ti99 is as compared to the Apple IIe and Tandy. So you would expect the same results, but I know that's not always the case with emulation.

Folly

@jamrom2

For every system in mame there is a driver.
Some of them are better than others, thats just how it is.

CVBS is the composite video output.
With the early raspberry pi 1 it was the yellow connector :
https://cdn.instructables.com/ORIG/FBD/EEDO/HZCJ4PQM/FBDEEDOHZCJ4PQM.jpg?width=2100

Now it's in the jack plug, so you need to have a cable for that.
And you need a TV that can handle old composite video.
You have to use a cable like this :
https://tinkersphere.com/1906-thickbox_default/raspberry-pi-a-plus-b-plus-composite-to-rca-adapter.jpg

Old camcorders, for example, used these cables also but some of them have colors swapped. So when using such a cable you have to measure how it's connected.

mitu

[...] CVBS could improve speed also.

Why do you think it will ?

Folly

@mitu

Well I have had some experience with it a couple of years ago with some emulators I don't remember anymore.
When using it it back then it definitely improved the speed.
But honestly I don't know if it will work with mame, so this has to be tested.

mitu

@Folly There's nothing that inherently favours using the analog video jack over the HDMI one. You may had better experience with a lower resolution, but I don't see how using one over the other would improve emulation.