8 Bit Hercules Graphics Card: Schematics?

The Hercules Graphics Cards for the PC and XT offered text and graphics capability in a higher resolution than comparable cards from IBM. I have several of these cards and they are usually the first choice for a quick install when working on a system. I'm wondering if anyone on the forum has ever seen anywhere a circuit diagram for the cards, say for example the GB-200?

The reason I ask is because this looks like it would be a really easy card to duplicate...

Thanks, Michael

I've never seen one, although they were certainly part of the earliest ERSO reference designs. I suspect that some of the Warsaw Pact country archives might have a schematic also.

The Far East clone HGC were among the least-expensive display cards that one could buy, so there was probably little interest in reverse-engineering them.

An interesting feature of the GB200 Hercules ISA Video Card is the use of socketed ICs. There is an MC6845P Video Controller, but more interesting are the two 40 pin DIP IC's labeled MHS HCT 'VIDEO 200" and MHS HCT "LPT 200". The MHS probably refers to Matra Harris Semiconductor, and HCT might indicate the logic family, however what puzzles me is what exactly are these chips? I can imagine a VPU for the video, but a similar chip for the parallel port?

It's too bad I have not been able to find out much more about what Van Suwannukul did to create the Hercules line of graphics adapters, as it seems to have the elements of an interesting and innovative story...

Attached a low resolution photo of the card for those with interest.

Michael

HCT is Hercules Computer Technology. These may have been custom chips manufactured for Hercules. I suspect they replaced a number of the chips from the older cards. Here's a picture on Wikipedia. http://upload.wikimedia.org/wikipedia/commons/6/64/KL_Hercules_HGC.jpg

The GB200 looks a lot like the Zuckerboard clone. Several 40 pin custom ICs.

The best place to start if you want to make one from scratch would be an early Taiwanese clone. These used no vendor-unique custom ICs.

Now, if you wanted to do something special, you could do the Herc Plus (downloadable fonts) or the InColor

Doing an online search on the Hercules Cards and their history, I found an interesting article in 'Infoworld' from June 17, 1985 with an interview with Kevin Jenkins at Hercules Graphics Corporation. Speaking about the competition and the small size of their graphics card "Hercules claims its design engineers have applied gate array technology to the development of the boards to reduce the board's semiconductor count." This suggests to me that on the GB200 board the "Video 200" and "LPT 200" 40 pin DIP IC's are gate arrays. Looking at the semiconductor offerings available from Matra-Harris at the same time... yes indeed, they were active in the technology.

Anybody want to reverse engineer a couple of 40 pin gate arrays for me?

Michael

One more piece of information about the GB-200 Hercules Graphics Card from a 1987 article in 'Infoworld'... This particular video card was designed be comparable to the IBM Color Graphics Adapter (CGA).

I didn't know Hercules made CGA cards! Something to watch out for if you are intending to pick up a Hercules card to do Hercules graphics.

Something to watch out for if you are intending to pick up a Hercules card to do Hercules graphics.

Click to expand...

Yes, I found this out the hard way. I've been trying to get my hands on a Hercules card (HGC, HGC+ HGC InColor) and I finally paid money for something labeled Hercules only to get a GB200 in the mail today.

Pros: half-length board, parallel port
Cons: No composite output, not a hercules mono card

I have no need for this thing. Anyone want to trade me a Hercules mono card for it? (I need something that can actually do Herc 720x348 video modes, I don't care if it's a clone card).

I have a clone mono card labelled "DUAL VIDEO ADAPTER 188600-001 Rev C" with four DIP switches that I haven't been able to find a manual for (TH99 did not help). It current works as an MDA with all DIP switches ON, but MDA != Hercules.

I've got a Zuckerboard, as well as a couple of Herc Plus (downloadable font) cards, but they're not going to help you if you want to reverse-engineer the thing. Both contain proprietary gate arrays. Neither has composite output--as far as I'm aware, no monochrome Hercules card ever dead.

Chuck(G) said:

I've got a Zuckerboard, as well as a couple of Herc Plus (downloadable font) cards, but they're not going to help you if you want to reverse-engineer the thing. Both contain proprietary gate arrays. Neither has composite output--as far as I'm aware, no monochrome Hercules card ever dead.

Click to expand...

Different poster -- I just want a working Hercules Graphics card. I'll PM you.

Trixter said:

for something labeled Hercules only to get a GB200 in the mail today.

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Could be worse, could be the GB50... which was just a MDA knockoff. No fancy graphics mode.