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Can anyone identify this "frame buffer"?

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2icebitn

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It's such a generic term, but I don't know what else to call it. There isn't even firmware, as such it must be an addendum to another card I guess. If I were to plug it in, what should I expect to happen? Line up multiple NTSC monitors and get to play the same game across multiple monitors?

IMG_20190106_180838.jpg

In case visibility leaves something to be desired, the white chip is a upd7220. As I read it seems it has a bit of onboard ROM, but not much. Intriguing. And no identification whatsoever, which is really weird.

Also components I've never seen otherwise:

IMG_20190106_190651.jpg

And some numerics on back:

IMG_20190106_190740.jpg
 
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My first guess was that this PC was part of a security system, thus supporting several monitors. But the upd7220 is a special video IC capable of drawing circles, line, etc., something not needed for a security system. So my second guess: a CAD/CAM system with multiple monitors.
 
CAD/CAM with composite monitors? There are high resolution monochrome monitors that receive a composite signal, not ntsc compatible, but I've seen one only with bnc connections.
 
I'm a bit confused about the 6 connectors. If there had been 5 I'd guess they were R, G, B, Hsync and Vsync, and they just used RCA jacks because it was cheaper or easier for them.

Since there's 6, maybe it's RGB sync-on-green, both inputs and outputs, and this card supports video overlay? Or maybe it's a pair of RGB sync-on-green outputs meant to drive 2 monitors. Or maybe 1 RGBHV plus a composite output?

I don't think they could fit 6 BNC jacks on the plate so I understand using RCA jacks instead, which fit into a slightly smaller space.
 
A 7220 on a regular IBM PC...interesting! 7220s were more commonly seen on early members of NEC's APC lines as well as the Japan-exclusive N5200 and PC-98 systems the APCs were localized versions of.
 
Isn't that what the Rainbow used?

IIRC, it's not really suitable for multiple displays. I'm stumped by the 6 connectors too. 5 would make sense, but there's no good reason to substitute RCAs for BNCs (or even TNCs). Even if it's used for overlay, it would be pretty bizarre to have that many connectors.
 
Yup! DEC licensed the 7220 for a couple of their systems - even some of the larger minicomputer-scale stuff! I think some of the Welsh Dragon computers did, too? The 7220 was one of the more versatile graphics chipsets of it's day.
 
KC9UDX said:
IIRC, it's not really suitable for multiple displays. I'm stumped by the 6 connectors too. 5 would make sense, but there's no good reason to substitute RCAs for BNCs (or even TNCs). Even if it's used for overlay, it would be pretty bizarre to have that many connectors.
Click to expand...

I wondered if it was actually two sets of inputs, and one set of outputs. I noticed the last two were spaced differently.
Might do just fine for a store display or a wedding video. I have my parents wedding on VHS, and text overlays + scene switching (no effects) were all that was used there.

All just guess work though , hopefully someone recognizes it. I'm curious now
 
I'd also be surprised if there wasn't at least 1 aftermarket card for the PC that sported the 7220. The 6845/6545 was more versatile then one might suspect, given CGA graphics in particular was so blase'. IBM should have designed the CGA with an upgrade path in mind. But they rarely ever took my advice.
 
KC9UDX said:
Isn't that what the Rainbow used?

IIRC, it's not really suitable for multiple displays. I'm stumped by the 6 connectors too. 5 would make sense, but there's no good reason to substitute RCAs for BNCs (or even TNCs). Even if it's used for overlay, it would be pretty bizarre to have that many connectors.
Click to expand...

6 could make sense. Some Japanese computers output R, G, and B, separately, so this could be 2 x RGB out, though I doubt it...
 
It's a Number9 computer Revolution 512x32 card. One plug for each R/G/B and V/H sync. Don't remember what the manual said about the 6th plug, but might be external sync for the optional genlock expansion module.

It should be able to sync on green according to the manual, but it has to be configured to do so (int sync instead of ext sync)
 
One of the PALs decide on the memory mapping, which might possibly overlap with VGA or CGA or even the top part of conventional memory.

When it comes to using the card, you probably need to setup the uPD7220 registers and write to the framebuffer RAM and palette. The 512x32 does not support hardware graphics plotting.

I can try to dig up through the manual. I also found some diagnostics programs and drivers through the web wayback machine, but be advised that the card might perhaps not work if the computer/ISA-bus is too fast. Also, most programs supporting such cards are usually hard-coded to use them as a secondary display or has dedicated drivers on a per-program basis. These cards were never intended as a primary all-purpose graphics card.
 
Anything you can dig up would be GREATLY appreciated. I actually wanted one of these cards for a long time. How ironic (or numb skullish) that it was right under my nose. Didn't even know much about them LOL. The name sounded cool
I hadn't realized until quite recently it was named after a Beatles song. I had thought the name bespoke it's raw power.
 
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