Some arcade cores signal not working on my flatpanel

[metal_slugger]

Hi
Luckily this happens with a minority of games. A few arcade games I try will not display properly on my Samsung flat panel TV. When the issue occurs, the game displays very briefly, maybe showing the boot screen or game title screen briefly, then the screen goes black and my TV states the the signal is not recognised, and I have to reset the MiSTer or guess the key combination to choose a new core. This can happen with horizontal and vertical games.

I understand that the original arcade machines themselves used a range of different resolutions and frequencies but if the MiSTer is supposed to conveniently convert and upscale all those various signals to 1080p60 for my TV to show, why do some arcade cores not display? And is there a fix I can do for the ones that have the issue? Thanks

[zakk4223]

What's the value of video_mode and vsync_adjust in MiSTer.ini?

Also examples of which games don't work.

[metal_slugger]

What's the value of video_mode and vsync_adjust in MiSTer.ini?
Also examples of which games don't work.

vsync_adjust=2

video_mode=8

video_mode_ntsc=8
video_mode_pal=9

There are numerous games that have the problem, here is three examples

Trojan (Romstar) = briefly shows the Trojan title screen then my TV goes to "This resolution is not supported"
DoDonPachi = Briefly shows some garbled horizontal lines then my TV goes to "This resolution is not supported"
Horizon (Irem) = briefly shows the game title screen then my TV goes to "This resolution is not supported"

Thanks!

[zakk4223]

vsync_adjust=2 retains the original vertical refresh rate of the arcade core, it may be that your panel can't handle them. Horizon may be especially problematic because I think that's around 56Hz. Trojan should be 60hz, tho.

There's another possible issue: vsync_adjust calculates a pixel clock rate based on the input and output parameters. According to Sorg in a issue I had long ago, some frequencies are impossible to generate, but you can try changing the output video mode and that might help. Try video_mode=9 as a test and see if Trojan works. (It will still run at the game's refresh rate, not 50hz). If that fixes it then you can just set a video mode for that specific game in the ini.

[metal_slugger]

Thanks zakk4223. Thanks to you I have now worked out how to set custom ini settings per core and I have found that Trojan and DoDonPachi (cave core) works with vsync_adjust=0.

Unfortunately Horizon (and seemingly any other iremm62 game) doesn't work with either vsync_adjust=0 or vsync_adjust=1 or video_mode=9

[FoxbatStargazer]

Its very odd if any core does not work with vsync_adjust=0. Mister should be outputting the resolution and refresh specified by your video mode at that point, regardless of what the core is doing. Maybe check that you have the right core name in the ini, or try setting it in global settings just to test.