Confusion about overclocking AFX

[Rodney Hester]

Been dinking with this for a while now, and the harder I look, the more confused I become.

 

With the overclocked kernel's governor set to userspace and the max frequency set to 816000 (both confirmed by walking the entire sys tree), using the AFX retroplayer _still_ results in missing player sprite and/or asteroids in Asteroids.  This suggests that either the issue is something else with the OC kernel other than the CPU speed (or Mali clock, I've tried that too), or the CPU speed isn't _actually_ being reduced by scaling_max_freq.

 

Any thoughts?

[Draxxon]

This runcommand is for NEXUS test purposes only if you want to see how it can be used on a per extension basis.

The test runcommand is set to run .ziml files at the three different speeds - 816, 1008, 1200.  So to see this in action:

Drop the runcommand in /emulator.

Startup.sh goes on the root. (Keep your old files, these are just test files.)

Boot your AFBX and jump to the LFB roms (this is so you have whatever magic in the retroplayer.ini allows select to add coins in retroplayer.l)

Then run that game and it will run three times so you can see the difference - 1) slow and choppy, 2) a little better, 3) almost perfect.

 

RocketFan also set it up to run .a26 ROMs twice- once at 816Mhz and one "full speed" at 1200Mhz.

Try Asteroids.  You can see 3 things:

1) For sure it runs faster at 1200Mhz - Maybe too fast.

2) the 816Mhz DOES NOT solve the missing player/asteroids bug. (or fix battlezone/moonsweeper/mousetrap either).

3)You still have to use retroplayer.9/.a269 to get that fixed.

I think that the missing sprite error is in the retroplayer.x itself. If not that, then its not jiving with something we've changed. And even if not that, it still seems that the AFB9 retroplayer.9 is superior to the AFBX's retroplayer.x, at least as far as .a26 games. retroplayer.x has the better scanline filter is all I can see. Playing River Raid stock on an AFB9 and on an AFBX, it is deff better on the 9. And I believe its not just River Raid, but ALL games across the board. The X's gameplay is choppy, I believe the difference is in the slower clock speed and the retroplayer.x.

 

runcommand startup.sh

test.rar

Edited April 30, 2021 by Draxxon

[Rodney Hester]

OK, so our experiences are the same - with the OC kernel, _even clocked at 816MHz and with RPX_, you still get bad behavior in Asteroids.  That mystifies me, because it means whatever RPX doesn't like about the OC kernel image, it's actually *not* the overclock itself (my plan was to throttle the clock for certain ROMs by md5sum to prevent the RPX-related issues, thinking it was a speed issue).  I'm just trying to better understand what the bad interaction is between the OC update and RPX...my ultimate goal is RPX across the board at 1.2GHz, with whatever per-game adjustments are required to make the small number of problematic games "behave" with RPX (my fallback position is to use RP9 for those games, but the difference in scanline intensity is a killer).

[Draxxon]

I understand bud, For me, I never use scanlines. I dont like them. So it doesnt matter to me. Aside from that, and even aside from the missing sprite issues, I STILL feel retroplayer.9 is superior. Gameplay (smooth vs choppy/dropped frames) has to be more important than scanlines, IMO. I realize you are trying to keep the AFBX as stock as possible, but I feel like the AFBX was a copy paste of the LFBs and its not as good as the 9 was. I feel like the 9 was tweaked to play atari, and the X just got settings from the LFBs for whatever reasons. I've seen similarities, like box art sizes, between the two (LFB & AFBX) that were changed from the AFB9, and that just makes me wonder... what else was copied over and changed... something in the retroplayer??? because gameplay suffered.

Edited April 30, 2021 by Draxxon

[Rodney Hester]

Yeah...ugh.  LOL  The RPX thing *really* bothers me, because it just makes no sense.

 

That being said, I at least have dynamic selection of RPX vs RP9 based on md5sum working now (and tremendous thanks to many of you for helping me get there!), and I've reverse-engineered as much as the platform as I think I can usefully do...I at least now have a very clear understanding of how all the plumbing works, even if not necessarily _why_ LOL.

[Draxxon]

RocketFan onced mentioned to me "I wonder if the RPX I chose way back when is the cause (of the sprite bug)". 

Which made me wonder, how many "RPXs" are there? did they change at all from official update to official update? did rocket use the RPX from my A.T.A.R.I. pack that was built off of the standard V.0.1.18? or did he use the deluxe 0.1.9 version RPX? or the standard 0.1.21? are there even any differences in them? 

Edited April 30, 2021 by Draxxon

[Rodney Hester]

All excellent questions - would love to know myself.

 

One thing that may be a consideration - you may already have experience with this.  RPX obviously supports paddles (poorly-ish, but it does) - didn't RP9 not work with paddles unless you change the value of the potentiometer?  (I'm assuming that was a function of RP versus libstella.)

[Draxxon]

 

I was told it was in the hardware of the AFB9s controller ports and not the software. I never modded my 9 or a pair of paddles to make them work on the 9. It seems atgames purposefully jacked with the port so only their paddles would work, and then they never sold any.

We are still learning the intricacies of everything and i only have so much time to experiment. Im not very knowledgeable so I use my time to add working cores. It's all I've figured out. Most of my time is spent just adding the content. And some testing. I rely on your guys feedback on how to proceed. We have swapped RPs recently before. we are trying to find the way to make both the 9 and the X optimal and equal.

If you have ideas or insights that could work better, please let us know!  

Edited April 30, 2021 by Draxxon

[Rodney Hester]

I think I've reached what is (for me) a reasonable compromise for now - instead of keying off md5sum, I just look for _RP9 at the end of the ROM filename.  If it's there, I use the FB9 retroplayer, otherwise FBX's.  Saves having to hack runcommand and seems a little cleaner implementation.  Sorry, I just can't handle those heavy scanlines with River Raid, it looks AWFUL.  Maybe someday we'll figure out what the problem is between the OC kernel and FBX's retroplayer and get truly the best of all worlds.

 

I'll test paddles later this evening to be sure they work as expected.

[Draxxon]

I think it would be worthwhile to look at the various versions of the "RPX" and see if they vary.

I also wonder if the scanline filter of the X can be swapped into the 9s RP ala carte.

I also wonder if bezels could be displayed on top of the viewing area instead of underneath and if then custom overlays could be used as filters.

Edited April 30, 2021 by Draxxon

[Draxxon]

1 hour ago, Rodney Hester said:

I just look for _RP9 at the end of the ROM filename.  If it's there, I use the FB9 retroplayer, otherwise FBX's.

 

Sorry, I just can't handle those heavy scanlines with River Raid, it looks AWFUL.  

We had done something similar in nexus recently. We had flipped to the the AFBX retroplayer and used the .a269 extension for roms that needed it on a per game basis, purely for the scanlines. The problem with that is further testing found that the missing sprite bug was in far, far more games than just Asteroids and the other 3 that get mentioned. And, contrary to popular belief, adjusting the clock didnt fix the missing sprite bug. Also, games played more smoothly overall with the RP9 in general. You would have to go thru and test all the .a26 games and change the extensions and image names and ini entry for them all. And, even then, the RP9 set up from before was still superior in the gameplay department. I believe the thinking was, with the overclock, maybe the x player would perform on par with the 9. It did not. The only reason the X player got kept in the mix at all wasnt for the scanlines. There were a handful of games that the RPX will run that the RP9 will not. RP9 was speed/gameplay and the RPX was compatibility/accuracy??? we switched back to the RP9 for the next release. RPX was inferior, IMO.

About the scanlines, IMO and humble opinion, they BOTH look horrible. to me they are equally awful. they are just different than each other. I'm not trying to be negative nancy here, just pass on what Iv observed and my honest opinions. I hope they help! But, stay true to your vision for your project! I'll help any way I can.

 

Edited April 30, 2021 by Draxxon

[Rodney Hester]

I do feel like I'm reinventing the wheel a bit.  *laughs*

 

You pretty much had me convinced to throw out the baby with the bathwater and go all-in on RP9...but when I use it with River Raid (with or without scanlines), it's very noticeably juddery, even with a 1.2GHz clock - in fact, it stutters like RPX does at 816MHz.  RPX (and River Raid at 1.2GHz) is smooth as silk.  Any idea why?

 

It seems for 2600-only, unless I'm missing the obvious, you're actually better off with RPX at 816MHz...the only thing that I can find that misbehaves in that configuration is the bit of juddering you see in River Raid, but everything else is (as close as it's going to get to) fine.

[Draxxon]

"RPX (and River Raid at 1.2GHz) is smooth as silk.  Any idea why?"

 

Maybe because its running at 80fps?

The 9 plays River Raid Smooth, Out Of the Box. The X does Not. I wish I had a video 

of the X playing River Raid before the OC. It was horrible. It ran around 50-60fps and 

dipped to like 30 or 40 randomly or whenever you used rewind. Rewind i felt has something

to do with things too. turning it off can sometimes help slow games. This video AFB9Gold stock settings

vs AFBXD 1.2Ghz with RP? - I dont remember, we can flip them at will, maybe it was RPX???
Video isnt great, the stuttering in gameplay was from the capture card and not in game.

 

P.S. Don't go throwing perfectly good babies away because of something I say, I

      am, in fact, just the art guy. Stay true to your projects vision.

      Also, River Raid is the greatest Non-Paddle game for a2600 in my opinion, so it

      gets priority over everything else in my vision. If smooth river raid makes all the other 

       games judder, I wouldnt even notice. lol.

Edited May 1, 2021 by Draxxon

[Rodney Hester]

Struggling to understand the (relatively) poor performance (just for River Raid!) using the FB9 retroplayer on the FBX at 1.2GHz.  It ought to be absolutely perfect performance-wise...but isn't even close.  The more I stare at this little box, the more confused I become.  LOL

 

Yeah, I get it.  It's a toy.  But damn, it's a toy with SO MUCH potential.  *sigh*

 

My RetroN 77 is my daily driver, but this little guy has...personality.  It'd be an awful shame to park it on a shelf for display but not play it with passion.

 

I'm not giving up yet.  LMFAO

[JeffDewe]

On 5/1/2021 at 10:00 AM, Rodney Hester said:

Struggling to understand the (relatively) poor performance (just for River Raid!) using the FB9 retroplayer on the FBX at 1.2GHz.  It ought to be absolutely perfect performance-wise...but isn't even close.  The more I stare at this little box, the more confused I become.  LOL

 

Yeah, I get it.  It's a toy.  But damn, it's a toy with SO MUCH potential.  *sigh*

 

My RetroN 77 is my daily driver, but this little guy has...personality.  It'd be an awful shame to park it on a shelf for display but not play it with passion.

 

I'm not giving up yet.  LMFAO Retron 77 is a great system.