YPbPr - Rolling/unstable image issue on CRT's (NTSC)

[amerika13]

Last night I hooked up my MiSTer for the first time via the new I/O board I got. I am using an VGA to YPbPr cable. I also setup the MiSTer.ini file to include YPbPr output. With the NES core, I get a rolling image on both my Sony CRT and my PVM. However, the video captures fine without any rolling via my internal Micomsoft capture card which is also capturing the YPbPr signal (I have Extron Crosspoint switches).

So there is something that the NES core is outputting that my CRT's do not like but that my capture card corrects. I do not get this issue with the Genesis, TurboGrafx or SMS cores. I also do not see the issue via HDMI out for any core.

I know that analog video out isn't a huge priority but I figured I'd create an issue for tracking for a possible solve down the line.

Example video: https://www.youtube.com/watch?v=N77U3pke3iw

Example image: https://cdn.discordapp.com/attachments/497146208297680907/509192111711715338/IMG_20181105_202719.jpg

[sorgelig]

What VGA YPbPr cable you use? Do you know that MiSTer outputs YPbPr directly without external circuit unlike MiST? So, YPbPr are just 3 wires directly connected to RGB and switch SOG/Y should be in ON position.

[amerika13]

https://www.amazon.com/gp/product/B001T6OHNU/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 is the cable I use. So no circuitry/converter involved I believe.

This is the position my SoG switch is in: https://photos.app.goo.gl/z6EfMaoN6ogiARqZ7 Which looks like On to me.

[sorgelig]

Everything looks correct. Currently i don't know why it happens.

[amerika13]

Sentient6 on the Classic Gaming Discord does not have a GitHub account but asked me to post his issue which might be caused by the same issue. He's using a different Component cable that is feeding into a RetroTink 2x - http://www.retrotink.com/

sentient6: root menu ntsc version over component to Retrotink 2x: https://cdn.discordapp.com/attachments/497146208297680907/509208368305405965/image.jpg

sentient6: NES over component to Retrotink 2x: https://cdn.discordapp.com/attachments/497146208297680907/509208573943742475/image.jpg https://cdn.discordapp.com/attachments/497146208297680907/509208912327737345/image.jpg

sentient6: But Genesis is happy: https://cdn.discordapp.com/attachments/497146208297680907/509209815369777163/image.jpg

I also have weird color rolling (but the words are static) over YPbPr in the main MiSTer menu. But it's not present in the core menus for Genesis or TG16.

[svirant-ds]

I have a similar issue with only the NES core as well. Tested this against all releases. I am using RGBS over a VGA to 5BNC cable to a Sony PVM using the following: https://www.amazon.com/gp/product/B001UJMGZC/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

The picture, although in-sync, has dark bands across parts of the screen and overly bright in others. This is only for the NES core, the Genesis and TG16 cores look fine. Examples below.

Looks fine on Genesis and TG16

[sorgelig]

Try to disable overscan in NES core. It seems blanking interval is not enough for your TV.

[svirant-ds]

Thanks sorgelig! I swapped out the PVM for another one I had and this one is okay with the signal, so things are all good! The previous PVM works great for everything except the NES core but I don't mind if this other PVM doesn't have an issue with it.

[paulb-nl]

This may be caused by too long Hsync/Vsync. Hsync is 41 cycles but should be 25. Vsync is 9 lines but should be 3.

HSync <= ((hc >= 277) && (hc < 318)); VSync <= ((vc >= 245) && (vc < 254));

[ironminh]

Hi fellow retrogamers,

I just set up my MiSTer platform and enabled the ypbpr in the config file. I purchased these cables VGA to Component cables on Amazon:

https://smile.amazon.com/gp/product/B001VRQIIY/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Connected them to my Toshiba CRT and the main Mister screen is flickering very similar to amerika13. Here's a video of my experience.

https://youtu.be/_2LvJBkxsnw

For some reason the Main screen to MiSTer is flickering and rolling but when I boot up the console cores its ok. Any help is greatly appreciated.

[sorgelig]

May be your TV doesn't support PAL.

[amerika13]

Hi fellow retrogamers,

I just set up my MiSTer platform and enabled the ypbpr in the config file. I purchased these cables VGA to Component cables on Amazon:

https://smile.amazon.com/gp/product/B001VRQIIY/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

Connected them to my Toshiba CRT and the main Mister screen is flickering very similar to amerika13. Here's a video of my experience.

https://youtu.be/_2LvJBkxsnw

For some reason the Main screen to MiSTer is flickering and rolling but when I boot up the console cores its ok. Any help is greatly appreciated.

That is due to the MiSTer menu being 50hz PAL. Anybody who has an NTSC CRT TV is going to run into this issue (most LCD's will handle it just fine). The "fix" is to get Rysha's NTSC menu located here: https://github.com/Kitrinx/MiSTer_NN/tree/master/Menu

So my issue, which might have been resolved (I stopped using analogue out due to all the core issues), is different from yours.

[sorgelig]

There is a way to use standard Menu with 60Hz. But i won't tell you how! Tired of users who don't like to learn or at least read before posting.

[ironminh]

Thanks for the feedback everyone. I read through the thread and thanks amerika13 for your info. I'll try it tonight and keep you posted.

[ironminh]

amerika13 thanks for the solution. I used Rysha's NTSC menu successfully. I did attempted to reconfigure the MiSTer.ini file but wasn't successful in changing the core menu to display in 60hz I just kept getting sync issues. I thought maybe there's a better solution or maybe there is a way to configure the scaler to work the vga but unfortunately I can't find more information online. But again thanks for the explaining and giving me a solution.

[cyberluke]

May be your TV doesn't support PAL.

Sony PVM does support PAL and NTSC, RTFM