VGA converter problems [Solved]

Discussion about displays and related hardware including MiSTer filters and video settings.
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buttersoft
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VGA converter problems [Solved]

Unread post by buttersoft »

Hi, MiSTer newb here.

EDIT: sorry, i've done some more testing. And sorry to the mods, i keep editing this post. Will every post need moderating, or just the first...?

I can load everything fine on an HDMI monitor, and using a 31kHz PC monitor also works ok. It's when i set direct_video 1 to connect to a PVM that i'm running into trouble. I'm mostly using genesis core to test as i have no RAM.

I've tried a Tendak AV-107-BK and an HDfury2. The Tendak will load the menu, but on loading the genesis goes to a black screen with the occasional flashing glitch. The HDfury2 won't sync vertically at all. And trying it in component mode won't bring up a stable picture either.

My mister.ini is default here apart from:
composite_sync=1 (if set to 0 the picture just rolls as expected. And the Tenday still gives a black screen on loading a core)
vscale_mode=1 (i've tried 0 and 1)
hdmi_limited=2 (i've tried 0,1,2)
direct_video=1 (required for core timing at 15kHz, yes?)

I didn't think either the converters i'm using was bad, but if the HDfury2 won't work, does anyone have some suggestions as to what will? OR any other suggestions of course!

The MiSTer is an awesome project, and i'm looking forward to diving in deeper :)
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Re: VGA converter problems

Unread post by buttersoft »

So, on the Tendak, the menu works, but also the GBA core. Genesis and PCE do not produce any image, and i cannot bring up the menu (or see to bring it up, rather). I did try adding the 470R resistor to the sync line, but it did nothing. And neither did adding a 1k pot and dialling it around.

I also tested a third HDMI-to-VGA adapter, a no-name one i had lying around that looks identical to the one on the Direct Video page.

(https://github.com/MiSTer-devel/Main_Mi ... rect-Video)

It performs like the HDfury2, refusing to sync vertically. Horizontally seems ok.
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buttersoft
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Re: VGA converter problems

Unread post by buttersoft »

Well, I managed to get it working on the no-name adapter by turning off composite sync and mixing each sync line through a 1k resistor. Not on the Tendak though, it just refuses to deliver any stable signal over either sync pin in the Genesis or TGFX16 cores, while the menu and the GBA core still work fine with the above method.
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buttersoft
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Re: VGA converter problems

Unread post by buttersoft »

So... no one else has had similar problems? I have been hot-plugging the HDMI port a bit, which i didn't realise might damage it. Somehow i don't think that's the problem. Different cores are clearly doing something different on a 240p output signal, which i find interesting given they're reporting the same spec on screen and to my frequency counter. I wonder if the HDMI port is having other effects.

Not complaining about anything, really, just keen to better understand what's going on :)
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Re: VGA converter problems

Unread post by akeley »

I 'm using DV as well but haven't encountered any of the problems you describe. I connect to a CRT TV via VGA - SCART cable. My DAC has the chip which was mentioned in the wiki.
Perhaps it's something with your PVM. How do you connect to that?

Also, are you the crtemudrive-guide buttersoft? ;)
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buttersoft
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Re: VGA converter problems

Unread post by buttersoft »

Aaaand today i plug the no-name adapter in, and everything works perfectly through composite sync, no mess, no fuss. I mean, WTF.
akeley wrote: Sun Aug 30, 2020 9:18 am Also, are you the crtemudrive-guide buttersoft? ;)
Guilty, yes :) Which pisses me off because i feel i should handle stuff like this better, lol.

I need to update that guide to mention the MiSTer i guess, as a very viable option. It's just a shame it can't do interlaced modes for a video player.
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Re: VGA converter problems

Unread post by akeley »

buttersoft wrote: Sun Aug 30, 2020 11:53 am Guilty, yes :)
Nice to see you've joined this camp as well. The search for the perfect CRT box continues, eh ;) MiSTer is best-in-class for those cores that work with CRTs - the output is 1:1 (I measured with a tape vs OG HW lol), plus there's no faffing about with timings, drivers, etc.
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Re: VGA converter problems [Solved]

Unread post by buttersoft »

Oh yes, i'd agree. The MiSTer is amazing. Not as flexible as a PC, but when it works it can't be beaten.
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