Not that I have heard of (and I think I would have heard if somebody had done it). It's something I've had vague thoughts about doing from time to time myself, but it's pretty low on my list. There are a number of interesting possible paths to explore in the design space, from minor palette improvements using the same set of ICs, to doing a PAL version (which would ideally be paired with an 8088 running at 4.43MHz instead of 4.77MHz). A few years ago I started a thread over at VCF which might be of interest: http://www.vcfed.org/forum/showthread.php?302 … sy-CGA-redesign .

Pfffttt, hahaha, oh god, what the hell happened to that forum? Man it looked like ass and didn't work right the last time I was there and I mindlessly click that link only to find it looks like a five-year-old has drawn all over the walls now and then vomited undigested candy up on top of it. If it didn't need boiling off the face of the internet before, it certainly does now, at least Vogons has the decency to look like an early 2000s driver scam site or something. 😜

That aside, such a project would be interesting to see and I wish you luck if you pursue it, though sadly I'm out as I don't own a CGA monitor.

And for the record, fuck VCF. If you think I dislike the way things are run around here, ha, no, that place needs to go and die. A shame as there are decent members there, but there are also a bunch of elitist assholes and a completely useless admin.

HighTreason wrote:

And for the record, fuck VCF. If you think I dislike the way things are run around here, ha, no, that place needs to go and die. A shame as there are decent members there, but there are also a bunch of elitist assholes and a completely useless admin.

We want names! 😀

On-topic... There is a project to build your own 8-bit ISA VGA card, based on a Trident chip. I suppose the need for CGA never arose.

Yeah, I'm putting together one of the ISA vga card kits now. I'd honestly love to have a hand-made CGA card though, if for no other reason than to have a dual-head CGA/VGA setup.

I'd rather have an ISA "universal graphics card" with a fully programmable microcontroller, some RAM, VGA, DB9, composite & s-video outs.

FPGA 640x480 standard VGA graphics... thing.

https://dqydj.com/how-to-create-an-fpga-graphics-card/

I don't have much experience with larger microcontrollers, but I think a microcontroller wouldn't really be a good fit for a graphics card. There's a lot that needs to be done for each pixel (reading data from VRAM, looking up character sets and palettes, working out the next address, letting the CPU have a chance at accessing the VRAM) that is easily parallelized but on a microcontroller would have to be serialized, meaning you'd have to have a very high ratio of microcontroller clock speed to pixel rate. An FPGA would be a much better fit, and indeed people have used FPGAs to make graphics cards (though I don't know if anybody has done so in an ISA format).

reenigne wrote:

I don't have much experience with larger microcontrollers, but I think a microcontroller wouldn't really be a good fit for a graphics card. There's a lot that needs to be done for each pixel (reading data from VRAM, looking up character sets and palettes, working out the next address, letting the CPU have a chance at accessing the VRAM) that is easily parallelized but on a microcontroller would have to be serialized, meaning you'd have to have a very high ratio of microcontroller clock speed to pixel rate. An FPGA would be a much better fit, and indeed people have used FPGAs to make graphics cards (though I don't know if anybody has done so in an ISA format).

Well, for CGA/EGA/VGA-level graphics, a modern microcontroller would be good enough, I would think.
See this for example: http://www.pouet.net/prod.php?which=61197
They use an ARM microcontroller, where the outputs are wired up directly to a VGA connector (schematics included).

I suppose alternatively one may be able to wire up an Arduino/Gameduino as a graphics card: http://excamera.com/sphinx/gameduino/

Sure, a 168MHz ARM microcontroller can directly generate a VGA signal. There's probably a tight (maybe unrolled) loop running during active frame time which just blasts pixels to the output, and all the actual effects are done during horizontal/vertical overscan. Bear in mind that a demo like that doesn't need to do any interaction with an external CPU. If you tried to make a video card the same way you'd get a wait state on VRAM accesses possibly as long as 25us (45us for CGA), compared to the 1.7us maximum wait state for an IBM CGA. Having a wait state that long would probably mess up DRAM refresh and crash the machine. So during the active period you've really got to service the CPU as well as blasting out pixels, which makes it a much more difficult problem.

ISA video cards for sale on ebay are about the price of an FPGA or microcontroller kit. Is any new ISA VGA stuff being made for hobbyists? I want to see my 386 system post. I've found some books on the XT stuff but if there's already a core and a blog that would save me a lot of time.

Um, not sure. But you can make your own using an Trident TVGA9000i chip. That is an low-end design, however.
But it might be still good enough to do the usual CGA/HGC/EGA/VGA/SVGA modes. Except Composite CGA, of course.

ISA Super VGA card
http://www.malinov.com/Home/sergeys-projects/isa-supervga