Hercules has 32kb right ? this one is only equipped with 16Kb RAM ???

Anyone can help me with fixing that ?
Maybe someone own this Card and can show me Pictures of it, so i can set mine to the same settings ?-

Hi Matthias,

In the past, I've made a few experiments with HGC cards, but I don't own exactly that same card. 🙁

The original Hercules Graphics Card has 64KB in total, I think.

However, a card compatible to Hercules Monochrome can be running either in half mode (one screen page) or
full mode (two pages; the second page is in the CGA frame buffer space normally).

By default, the Hercules boots up in Half-Mode to co-exist with CGA (or a VGA card in lower modes).
Some utilities/drivers like MSHERC.COM also have a /HALF switch to force this mode.

Some clone cards also support both CGA and Hercules. since both original cards used the same Motorola CRTC chip.
So it might be possible that your card has/had a jumper combination to set the gfx type (mono/color).

Sorry, that's all that comes to mind right now.
The usual sources (Wikipedia, etc) have got more details that I can remember at the moment.

Edit: Your card has an LPT port installed. That rather hints to a HGC or HGC/CGA combo card.
Pure CGA cards normally had no printer port on-board.

Looks like it should be using an 8x14 character (or 9x14) BUT the character set is only 8 lines and bit 3 of the row address is being masked so that it wraps around to the first line again (repeating the character).

Assuming that fat chip at the top is the character set ROM (the one with 8722 date code), you could try to follow traces from there and see where they go. It looks like there are some extra pads over on the left for optional components/jumper blocks?? Likely two jumpers need to be changed, one to unmask RA3 and one to select a 14-line charset.

That sounds like a good idea. I'd also like to add that there might be a datasheet available for that rectangle chip on the left.
If so, it should also include a pinout with each data line being described in detail.
- Back then when I looked for my clone cards, there were such PDF files online, at least.

Yeah, i got CGA text and graphics mode working.. found some dead solder joints.

but most times i only get this:

the monitor is working fine, i tested this with other CGA Machine.
Seems something is defective.

if i leave machine off for few minutes and turn it on, it works.
Maybe a Capacitor is dead.

EDIT:
replaced deblocking capacitors on bus, 10uf tantal (one had 50 Ohm).
but this is only a small part of the problem 😉

i tried all combinations and found the one for hercules, but it will show 1 1/2 lines.. with one setting i had the correct output.. but then it woes again..
No picture at all, or scrambled output. can't reproduce it..

Maybe the DRAM is defective ?
but CGA works fine ?

i using the hercules monitor as second screen on my 486 now for testing the card (i don't want kill my XT)
switching to hercules with mode mono -> system freeze
switching to cga (in cga mode eg. mode co40 mode co80) -> works

no shades in cga.. sucks too:

looks ok:

Glad it works now! 😀

Maybe some utility can help checking the card.

I know of CGA Compatibility Tester, but using that is not without risk on a TTL/HGC monitor.
They don't like non-standard syncs, I heard (poof!).

Anyway, maybe some of the modes can be selected safely (Motorola CRTC tests ?).
Maybe even if the monitor is switched-off during testing ?!

Anyway, I'm talking too much again. 😅
I better stop making silly recommendations.