chelnov: CRT video issue on SiDi/MiST

[alessioscand]

Hi, I'm experiencing a strange issue with Karnov on SiDi.
Picture seems to repeat horizontally, and when scrolling it gets darker with rolling red or blue bands (as when a SCART cable is loose or isn't "fully" connected).

Video:
https://drive.google.com/file/d/10_vO1gu7pl1L8P_GnNPQ97JSk8wi4Wlv/view?usp=sharing

I'm using a MAME merged .251 romset with MRA (no errors at all).

Thank you

[squidrpi]

Same issue on the MIST and a Sony CRT.

[alessioscand]

Reading also other feedback in the forums, it seems that the issue occurs with a SCART cable, or otherwise with the scandoubler deactivated.

[gyurco]

That usually happens when the back porch area is too narrow (the space between hsync and active area).

[jotego]

The source code is currently broken for this core. See #324. That needs be fixed before solving this one.

[jotego]

@gyurco was this working for you when you worked on #324 ? Do you use a CRT screen?

[gyurco]

I don't have a 15kHz CRT at the moment :(

[alessioscand]

Hello,
I have my SiDi connected to the 15Khz monitor, and gyurco taught me how to compile with Quartus II, if I can be of any help...

[jotego]

Thank you. Attached is the latest version of JTKARNOV and also JTCOP. I'd be surprised if one works but the other does not.

Please check if it works correctly. These cores operate at 57Hz. Maybe that's too low for some TVs.

sidi.zip

[alessioscand]

Thank you. Attached is the latest version of JTKARNOV and also JTCOP. I'd be surprised if one works but the other does not.

Please check if it works correctly. These cores operate at 57Hz. Maybe that's too low for some TVs.

Robocop works well.
In Karnov I'm still experiencing the exact same bug of my video in the first post.

Thank you

[jotego]

The color signals were not gated by the blanking ones. @alessioscand try this one:

release.zip

[alessioscand]

The color signals were not gated by the blanking ones. @alessioscand try this one:

release.zip

It works perfectly! Thank you!