23 Aug
2018
23 Aug
'18
8:49 p.m.
OK, so the demo was with a "MODIFIED" card. :-) (admittedly a trivial one
that brought it in line with published schematic)
Which Int10h modes does it support?
QBASIC is presumably simpy using the INt10h modes.
The MDA by default was in Mode 7.
If it will do mode 3, then it can do Lotus in color, etc.
Obviously, it doesn't have the RAM to do any "high resolution" modes, . .
.
On Thu, 23 Aug 2018, Eric Schlaepfer wrote:
I'm not that lucky! But yes, an early card with
the light pen connector
should work.
The card I used for the demo is a somewhat later revision. I added rework
wires to match the schematic in the technical reference manual of the
earlier revision.
With either an early MDA card or a modded card, if you fire up DOS 5.0 and
have QBASIC, you'll find that the COLOR statement... just works! It's quite
strange.
On Thu, Aug 23, 2018 at 8:24 PM Fred Cisin via cctalk <cctalk at classiccmp.org>
wrote:
> On Thu, 23 Aug 2018, Ali via cctalk wrote:
>> Which revision MDA is this? I have an original NEC Multisync and I have
>> a tone of MDA cards including one in one the first 5000 IBM 5150s
>> produced. I would love to get color out of it just for the sake of doing
>> it. Do you still have your demo programs?
>
> Do any of yours have the 6 pin Berg connector near the top of the mounting
> plate? Some did. On CGA, that connector is for light pen.
> Supposedly some early MDAs had pins 3,4,5 connected (not connected in
> later ones). That MIGHT be the same ones as have the light-pen?
> connector.
>
> https://www.seasip.info/VintagePC/mda.html#cmda
>
> http://www.minuszerodegrees.net/5150/early/5150_early.htm