Would this work? Connecting a Mega Drive / Genesis to a flatpanel through VGA.

I connected RGB's Composite Sync signal to VGA's Vertical Sync signal. The TV accepted this. I did not try this on a bunch on HDTVs, just the couple I had.

 

RGBHV is separate horizontal and vertical sync which SCART doesn't offer. You'd want to match SCART's composite sync on horizontal, most monitors will accept that, but you'd probably need an LM1881 to generate the vertical sync if the screen needs it. That said Mott seems to have wired it the other way around and apparently it worked. Some sets are more flexible than others.

"On G" will be RGB Sync on Green which Sony monitors tend to like. In this case you need no separate sync signal but you would need a screen that knows what to do with it - apparently yours does. The Megadrive, though, doesn't output SoG, so you'd need to track down a way to generate that. A few transistors should do it, so I've heard.

Really if you want to take this further you'll need to grab a multimeter and figure out what's going where.

 

I actually just received a multimeter the other day, so I'll look up some pinouts and see if I can figure out what's going where.

 

I don't follow, Alchy. How would using a multimeter help you determine what kinds of signals your TV will accept over which pins? I suppose you could figure out by trial and error, but wouldn't there be a risk of damaging something if you did that?

 

I meant for continuity testing.

 

Well testing the Mega Drive SCART cable, I don't see the Sync line connected to ANYTHING on the SCART end (RGB are fine). Does this make any sense? I'd assume this is a major problem.

I'm basing it off of the info here:
http://www.gamesx.com/avpinouts/genesisav.htm

and here:
http://en.wikipedia.org/wiki/Scart

 

The reason is that the SCART Cable probably uses Composite Video for the RGB Sync. That's how my SCART Box to Sony PVM conversion works. Composite Video or Composite Sync is fed into the Sync on the monitor. Circuitry inside allows it to automatically strip the Composite Video and just get the Sync it wants. And just in general I don't think SCART has a Sync pin for RGB, pretty sure Composite Video is intended to be used for that.

 

Megadrive uses composite video for sync over SCART, as do most consoles iirc, so it's not surprising sync isn't wired. Again, you may need to build an LM1881 circuit to generate the kind of sync your TV is after. (EDIT: beaten to the punch by Mott.)

First thing to try would be piping the sync that the console generates (assuming it actually does on that pin) to the set, since the cable isn't doing so.

 

Hmm... I was hoping I wasn't going to need to get my hands dirty, but it looks like that's inevitable at this point.

So is the best approach to eliminate the SCART aspect completely at this point? I was hoping I could standardize on SCART connectors at some future point.

Also, which sync should I link the Mega Drive sync to? Horizontal or Vertical?

 

I'd try Vertical first, but if that doesn't work, try horizontal.

Also you may in general want to be aware that on a digital display like an HDTV, the MegaDrive isn't necessarily going to look that great. It should look better with RGB than Composite but I generally don't recommend playing older consoles on digital tvs.

 

Well, as I mentioned earlier in the thread, my Dreamcast over VGA is very sharp (it looks like bypasses the blurrier scaling it does to other signals). That is the primary reason I wanted to try this. That being said, I do have S-Video coming out of it and it's currently hooked up to a CRT and looks really good. Perhaps I should take a step back and just enjoy it as it is.

 

If you have S-Video from your MD on a CRT, you may not really need to bother with RGB. RGB on a Digital Display, will probably not look as nice as S-Video on a analog CRT. The only way I think it would look better is if you were using an emulator which could output a better signal for the HDTV.

And I'm sure your S-Video probably looks quite a bit better than the regular composite video. I never realized just how bad it was till I got the RGB. But then going back later comparing emulator shots to the Composite, there was a huge difference I could have seen right there. Between RGB and emulators there is virtually no difference. Based on general colors and sharpness.

 

Emulators run in high resolutions and look wrong. Let's not go down that route.

Megadrive's sync should be hooked to horizontal. This is the standard. No harm in trying vertical, either way.

The reason VGA looks sharp is because it's a progressive 640x480 signal (480p), so only minimal scaling need occur. As far as the set is concerned your RGB output for the Megadrive is a 480i signal and will be treated as such, i.e. deinterlaced, scaled, and quite possibly heavily filtered (though this is less likely on the VGA port). I agree with what Mott says - I'd go for the CRT with S-Video over the digital screen with RGB.

 

To be perfectly clear, my point was if you want decent looking Genesis games on your HDTV, emulation will provide better overall image quality than the real system, unfortunately. Real analog displays are always best since that is what they were designed to use.

 

Thanks for that clarification. I suppose I will just stick with my S-Video / CRT until the CRT dies in the far distant future.

 

And when it does, have it repaired.

 

Thanks again for all of the info guys.

 

I don't want to nag, but I run my emulators all in native res on my CRT TV through a home built vga->RGB scart cable for that completely authentic graphical experience.

 

Unless you can swing 240p then older games won't look right - no scanlines.

 

Don't they make videocards that will output an standard, interlaced RGB signal? I think they're mainly intended to be used with arcade monitors but don't see why they wouldn't work with a regular RGB TV as well. However, I think you have to have special software to use it.