I have a Paradise EGA card HEGA IIIB, which works mostly fine. Text mode and 640x350 works like a charm. Only games running in 200 line modes (320x200 or 640x200 show lots of noise and flashing green bars that race through the image. What could that be and how can I debug this? I have multimeter and oscilloscope to measure stuff.
See video here: https://youtu.be/p4QXrXln9cU
Pictures of the card:
PS: Is there a manual for this card available? I can't find anything. there are 3 jumpers that I can set. The DIP switches seem to be rather obvious, although there is a 5th switch probably for autosensing the monitor type.
Identified the issue: this EGA card derives the clock for the 200 line modes from the ISA bus. And that is broken/iffy on my 286 board as I found out. My 486 drives the card without any issues.
286 *will* have this clock, as it is a must because 286 did have to drive CGA and MDA cards back in the day. I know this as I had this set up.
Fix the issue on your 286 then.
Cheers,
Great Northern aka Canada.
What an exceptional card!
It is an EGA card, but at the same time it has a 26-pin male pin header connector on board. Connectors like that began to exist starting from circa 1991-1992 when VESA began to standardize the IBM VGA card Feature Connector. That connector originally was an edge connector on IBM VGA cards for several years before. I wonder if the 26-pin connector on that EGA card is something else.
(It is not at least the EGA feature connector. That one is 32-pin female pin header connector, and it is seen on that card on the top left, just the header is left unpopulated)
I'd be curious to know if you can locate hsync, vsync and dot clock signals on either, or *both* of those headers, the 26-pin male header, or at the pads of the unpopulated 32-pin header connector? If so, I might look to source one for my own tests 😀
