Build Your Own Arcade Controls Forum

Software Support => GroovyMAME => Topic started by: tonyt76 on February 20, 2021, 10:54:10 pm

Title: VMMaker Question
Post by: tonyt76 on February 20, 2021, 10:54:10 pm

In VMMaker under Edit Settings > Video Card there is a checkbox for (Add modes from mode list).

What exactly does this option do?

Title: Re: VMMaker Question
Post by: Calamity on February 21, 2021, 10:29:03 am

That option only applies to EDID emulation. By default a virtual EDID is created with just one single modeline (640x480). Checking that option adds the rest of calculated modes into the virtual EDID. This has some niche uses but generally it is discouraged, specially when usign super resolutions, because Windows will likely set the desktop to a super resolution on its own and produce an unusable desktop.

Title: Re: VMMaker Question
Post by: Zebidee on February 21, 2021, 12:32:29 pm

Wow thanks. This explains a lot  :o

Today I've been testing a composite sync input upgrade for the GreenAntz transcoder (so you can feed it csync via VGA as well as H+V).

Just found out that if you tick that "Add modes from mode list" box and are swapping between composite sync and H+V sync, frequently changing polarities and regenerating modeline installs, you can end up by default in this "640x480@30i" mode. Which I think is what Calamity is talking about. The modeline looks almost the same as "640x480@60i", including polarities, except under the oscilloscope where you can see the vertical part of the CRTEMU generated composite sync is inverted (positive). It goes the wrong way for normal csync. It can leave you with an unusable desktop on a TV, making it difficult to sync and fix things.

Don't know if that is a bug, but now I know don't tick that box!