Green artifacts and judder in CPS1

[chanunnaki]

Has anyone else experienced green vertical lines across the screen in Street Fighter 2? It's very distracting and will pop in and away every now and again, but stays for 99% of time. They are the most evident when there is a fade from one scene to another.

I don't know what's causing it and it doesn't seem to occur in any other cores/games that I've played. I've done an update_all and they are still there. They are only 1 pixel across, but once you see it, you can't unsee it.

There might be a problem with my IO board.

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Edit: Just tested a few other CPS1 games, Forgotten Worlds, SF: Turbo, U.N Squadron etc. and it's there too, but NOT in other Jotego cores like Bubble Bobble, Ghouls and Ghosts.

I will test the HDMI output see if I get the same thing.

[paulbnl]

Are you using component video from the IO board?

[chanunnaki]

Are you using component video from the IO board?

VGA output to a 1600x1200 Dell 2007FP.

I'm using this video mode:
video_mode=1600,64,192,304,1200,1,3,46,162000


I just tested at 1080P over HDMI and it doesn't have this problem.

[paulbnl]

It could be that simple DAC of the IO board is not good enough for 162Mhz. There were some changes in the vga_out module that are not yet picked up by Jotego I think which could improve timings.

If you want to use VGA out with that resolution then you should use a HDMI to VGA DAC. Though it doesn't make sense to use VGA when that LCD monitor also has DVI so you can just use a HDMI to DVI adapter.

[chanunnaki]

Thanks for the input, I will try DVI out next time.

It's a shame actually, because I was going to capture some 1600x1200 gameplay but this isn't a possibility with the way things are at the moment.

[ash2fpga]

I get similar artifacts in ao486 with vga out of the analog io board running at 1680x1050.

[chanunnaki]

I get similar artifacts in ao486 with vga out of the analog io board running at 1680x1050.

I created an issue on github and Jotego gave a little insight...

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Also, if you're experiencing this artifacting running at 1680*1050, then CPS1 is basically broken for now over VGA. I only tested on another monitor at 1024*768 and I think they are present there too, but I didn't spend enough time on it to really see them clearly.