On 9/7/20 2:26 AM, Veit, Holger wrote:
Could this be a PGC card clone?
https://en.wikipedia.org/wiki/Professional_Graphics_Controller
That had crossed my mind at one point, but there's no horsepower to this
card at all - it's just TTL, RAM, BIOS and the 6845.
The color output *appears* to be TTL level - or, at least, that's what it's
using at power-on. It's not impossible, I suppose, for it to be switchable
to some kind of analog mode, thereby giving more color depth.
I'm wondering if it doesn't have some form of high-resolution bitmap mode
for visualization, i.e. display construction would be processor-intensive
and intended for static images/diagrams. I don't know if that really makes
sense though because it would also imply having to switch the monitor -
i.e. starting the machine with a CGA type display plugged in, then
physically moving to something else later.
On the back of that, I just found this thread too which refers to an
identical board:
http://www.vcfed.org/forum/showthread.php?48718-3-Weird-Video-Cards-any-idea-about-what-they-do
... nothing there really "helps", but someone's comment about the medical
field and a higher-resolution display via the RCA jack is interesting -
that would at least get around the need to switch monitors (well, unless
there was some special autodetecting analog/digital monitor that was sold
to go with the hardware, I suppose).
It's a shame that the hard disk in the machine is either snafu or has been
wiped - the contents would have helped shed light on things. There's an
EPROM as part of the video hardware; anyone know of a DOS-based util to
poke at the contents and/or snarf them into a file on disk? It's possible I
suppose that there might be some useful strings hidden away in there.
cheers
Jules
