MiSTer Freesync and LG CX TVs - Not Possible?

Discussion about displays and related hardware including MiSTer filters and video settings.
Ashfall
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by Ashfall »

paulbnl wrote: Thu Sep 23, 2021 11:58 am So you are getting frame drops? My LG B9 has no issues with SNES or NeoGeo AES. Neogeo on MVS mode (59.17Hz) does have frame drops.
Yes, noticeable frame drops in Super Mario World on SNES and Metroid on NES. I wasn't looking for it, but noticed the frame drops in Metroid right away after getting the C1. I'll try a few other things tonight when I have time.

It would be great if there were an option like what the Analogue jailbreak has where it slightly adjusts the system speed to a 60.0 refresh rate for cases like this.
Ashfall
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by Ashfall »

I'm beginning to think the frame drops may only be specific to a few games. I did some more testing and here are my findings:

Nothing in the TV settings changes the behavior. I checked way more things than can be listed here.
General MiSTer settings do not affect the frame drops. Resolution, color depth, vsync_adjust 0,1,2 change nothing.

Focusing on only NES and SNES, I tried the Test Suite ROMS and a few games.

NES
  • 240p Test Suite (PD) v0.21 pinobatch.nes
    All scrolling tests are perfectly smooth, vertically and horizontally at every speed.
    Drop shadow test is perfect.
  • Metroid - Start of new game, run right to door, then left repeatedly. Frame skip happens in the exact same places, regardless of timing. Did not notice that pattern before. Tested with and without extra sprites.
  • Final Fantasy 1 - no frame drops anywhere walking in towns, with or without b-button dash.
  • Super Mario Brothers - no frame drops noticed in first stage, walking or running.
SNES
  • 240p Test Suite (PD) Artemio v1.03.sfc
    All scrolling tests are perfectly smooth, vertically and horizontally at every speed.
    Drop shadow test is perfect.
  • Super Mario World - Stage 1 (to the right of Yoshi's house on world map) - walking to the right shows no frame drops, but running to the right and left shows frame drops. They seem to be in the same general areas, but not exactly like Metroid. Tested with and without turbo CPU.
  • Final Fantasy II and III - Intros have lots of vertical scrolling and some horizondal. No frame drops.
I'll connect the MiSTer to my old plasma later to see if the frame drops in Metroid are happening there and I just didn't notice it before. That was the first game I fired up right after getting this new LG C1 OLED, and I noticed the frame skipping right away. Maybe just coincidence combined with OCD? I'll also try some other games and see if there are more that show frame skipping.

And I didn't notice any frame skipping in Neo-Geo or Genesis. I tried Samurai Showdown IV scrolling intro text and Sonic background scrolling.
Ashfall
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by Ashfall »

A few more NES games observations.

Gradius - No frame drops (use invincible cheat).
Castlevania - No frame drops, running back and forth on first screen.
Castlevania III - During vertical scrolling intro, frame drops approximately every 14 seconds.
1943 - Stage 1 frame drops in background water, but not clouds or ships or anything else (use invincible cheat).
paulbnl
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by paulbnl »

Ashfall wrote: Fri Sep 24, 2021 1:20 am NES
  • 240p Test Suite (PD) v0.21 pinobatch.nes
    All scrolling tests are perfectly smooth, vertically and horizontally at every speed.
    Drop shadow test is perfect.
It must be the games then. If the scrolling is perfect on the 240p test suite then the TV is not frame skipping. I am assuming the TV is on Game mode with Motion interpolation off.

vsync_adjust=0 should cause frame skipping in the scrolling test.
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by Ashfall »

paulbnl wrote: Fri Sep 24, 2021 3:59 am It must be the games then. If the scrolling is perfect on the 240p test suite then the TV is not frame skipping. I am assuming the TV is on Game mode with Motion interpolation off.

vsync_adjust=0 should cause frame skipping in the scrolling test.
Game mode off/on makes no difference. Yes, with vsync_adjust=0 there is frame skipping in the scrolling test.

I connected the MiSTer to my old Panasonic plasma TC-P65ST60, ran all the same tests and got the same exact results as on the LG C1.

So we are in agreement, it must be the games. Metroid prompted me to search for this issue on this websute and go down this rabbit hole. I guess I was scrutinizing my new C1 too much and noticed things that were always there in the game.
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Re: MiSTer Freesync and LG CX TVs - Not Possible?

Unread post by Dafoof »

Just found out about this thread, good to see that I'm not the only one who has run into trouble with VRR support on TV (this time on a Samsung QD-OLED)! I posted some observations there:
viewtopic.php?t=6667
Wonder if the artefact I see is linked to that problem you encountered, this would actually make sense: I get constant screen tearing (always at the exact same position, for a given non-60 refresh rate, and it is more in the middle of the screen for 50Hz than for 57Hz), as if Mister correctly communicates the expected refresh rate, but then the actual display happens at a different one, maybe still 60 like you.

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