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EGA Cards that have a composite signal through their RCA ports

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sqpat

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This is a question that gets asked from time to time, and I've been researching this in the past day or so, and there is a lot of conflicting information out there about this. The original IBM EGA card I believe wired its two RCA ports to the feature connector pins 4 and 5. Around late 1986 and early 1987 a few cards began to output composite signals through one or both of the RCA jacks. I compiled a small list down below, based off reading through some PC Mag and Info World magazines from those years as well as some posts in recent years here and on VOGONS. I do think the default behavior is that they do not output a composite signal as it would require additional circuitry and chips in general. It's also worth nothing that a composite output is probably a very poor quality display option for these cards, but it is really convenient.

I'm also not sure which of these cards only support composite output in CGA modes, and which ones do it in EGA or Hercules modes.

RCA Jack Does Support Composite:
ATI EGA Wonder (There were a few variants of this card. Some cost-reduced versions might remove support for this?)
Juko G7-A
Vutek EGA
IDEAssociates Overboard
VTech Auto EGA4+
TSENG EVA/480 ET-2000 EGA (Through Feature Connector adapter)


RCA Jack Does NOT Support Composite:
IBM Enhanced Graphics Adapter
Paradise PEGA1/Autoswitch cards
Quadram QuadEGA
Orchid TurboEGA
AST 3G, 3G Plus

Not Sure:
Genoa SuperEGA+
Video7 EGA Boards
Heath EGA Boards
Boca Research Multi EGA
Everex Micro Enhancers
DTK EGA Cards

I would love to expand the list if anyone else knows cards that support the feature.
 
Ooh interesting as this is a very common misconception and confused me at first with EGA cards. I've got 4 (3 working) EGA Cards: Paradise PEGA1A, Paradise PEGA2A, Juko UDL C3 and a Genos CHIPS & Tech (broken at present) - When I get a chance I'll see if any of these are connected or just Feature Connector...
 
FWIW, I’m fairly (not entirely) sure the EGA Wonder’s composite out is monochrome only; that may well apply to some/most of the others. The EGA Wonder specifically had it mostly for driving the internal composite monitors of portables like the IBM 5155.
 
The manual at minuszerodegrees says that it displays “shades” but that you can get color with extra hardware.
 
It actually wasn't terribly common for later CGA cards to be monochrome only on composite. Getting rid of the color signals does make for a much cleaner display on mono monitors. (Granted a "mode bw80" should give you the same view on a full-fat CGA output, but there are some programs that rudely ignore the "no color" setting and trash the display anyway.)
 
My Toshiba T1100Plus seems to only output mono on the CGA composite. I think I noticed it because I wanted to try the running 8088MPH.
 
Hello.

I recently got this Genoa SuperEGA+ model 4880 and the reason I got this card is that it is known to output composite signal from its RCA connectors.

Well, I've tried both RCA connectors, no luck. I see nothing. It does work with my EGA monitor and all good but nothing from RCA connectors.

If you can follow the traces on the back of the card, you can see that both RCA connectors are connected directly to the feature connector.

So it looks like these are not for composite output but just another feature connector like the original IBM EGA card?

What do you guys think?

IMG_0150.jpgIMG_0151.jpg
 
The ega spec and initial card by ibm specify that the connector goes directly to some of the feature connector pins. I forget the exact details. But I don’t think it was a popular feature and so presumably some manufacturers eventually broke spec (like with other features like the light pen)
 
EGA Wonder cards with dropped support. I believe those are EGA Wonder 800 and EGA Wonder 800+.

And regarding EGA Wonder's composite signal color/monochrome situation. I've tried to get some light on this quote from the EGA Wonder Manual: "The EGA Wonder NTSC output can be converted into Colors by use of an external device. For more information on this mode call ATI Technical Support Group." in this thread previously.
 
sqpat said:
The ega spec and initial card by ibm specify that the connector goes directly to some of the feature connector pins. I forget the exact details. But I don’t think it was a popular feature and so presumably some manufacturers eventually broke spec (like with other features like the light pen)
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The card is on the “Not sure” list of your initial post. So maybe you can update it to “dose Not support” list?

But I really hope it works somehow. All the articles on the internet tell the card does output composite signal from RCA connector.

I tried many different switch settings but none of them gives me a composite output. Do I need a specific software to turn on? I am now sure.
 
Those RCA jacks on EGA cards weren't meant to be CGA composite out. It doesn't seem like IBM ever had that in mind, and more to do with syncing with an external video board for video & graphics overlay. But what's worse, with a card like the Genoa SuperEGA card, the third clock on that board is pinned out to the oscillator pin on the feature connector. But that pin is supposed to be a clock INPUT and not an OUTPUT. So I'm not sure if anyone ever used the feature connector on cards like that. If they are complying with the IBM EGA spec, I doubt you'd get much through the feature connector on normal EGA cards other than a B&W display kind of like that ATI card, if it is close to 100% EGA compatible. You'd have to tack on some kind of add on board, which, some people might have come close to doing it? I'm unsure. I've only seen B&W. Virtually no EGA card supported composite out, other than a select few, and likely not going to be 100% CGA exact.
 
the3dfxdude said:
Those RCA jacks on EGA cards weren't meant to be CGA composite out. It doesn't seem like IBM ever had that in mind, and more to do with syncing with an external video board for video & graphics overlay. But what's worse, with a card like the Genoa SuperEGA card, the third clock on that board is pinned out to the oscillator pin on the feature connector. But that pin is supposed to be a clock INPUT and not an OUTPUT. So I'm not sure if anyone ever used the feature connector on cards like that. If they are complying with the IBM EGA spec, I doubt you'd get much through the feature connector on normal EGA cards other than a B&W display kind of like that ATI card, if it is close to 100% EGA compatible. You'd have to tack on some kind of add on board, which, some people might have come close to doing it? I'm unsure. I've only seen B&W. Virtually no EGA card supported composite out, other than a select few, and likely not going to be 100% CGA exact.
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So do you think it will output only B&W even if it works? That's sad. I guess I will just have to move on.
 
jk92 said:
So do you think it will output only B&W even if it works? That's sad. I guess I will just have to move on.
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To clarify some, of the cards that have built in advertised composite support, like the ATI, I think only did black and white composite for things like the compaq portable, because it was easy enough to do, and I guess that was preferred for a sharper display instead of "color smear" back in the day. The other option would have been an adapter, which I have not seen a color version that attached to the feature connector. There has been some talk about doing so, and I think there was a person looking at doing color, and I think he was able to produce black and white shades off the feature connector, but I don't remember seeing if he finished a color version. And when it comes to composite with the CGA-exact colors to run some demos and few games as of late or some of the games originally did actually do that, I suppose EGA cards are likely to be incompatible with it. Of course people that do know the CGA and EGA card programming can explain this more accurately.

I think people searching for more CGA options as of late may mean that CGA cards with composite seem to be drying up? I don't know why otherwise except that demos as of late are popularizing the concept. I find it funny, because I never knew about this composite stuff back in the day and only really hoped for VGA to finally bring good color. Very little really did support it back in the day as it ended up forgotten in the PC. In some ways EGA kind of killed it even... it just took a little while and game makers started to really pick up the quirky PC. As far as the demos today, I have not yet ran one. I will probably try later when I get a free day :)
 
jk92 said:
The card is on the “Not sure” list of your initial post. So maybe you can update it to “dose Not support” list?
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Hmmm.. Looks like I can't edit the post anymore. Haha. Perhaps there is a maximum edit duration for posts on vcfed, I did not realize that.
 
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