22 Nov
2006
22 Nov
'06
4:36 p.m.
On 11/23/06, Chuck Guzis <cclist at sydex.com> wrote:
On 23 Nov 2006 at 12:09, Ethan Dicks wrote:
> I think it's because it was the first home computer that could run two
> OSs *at the same time* -- ISTR there was a way to run an MS-DOS and an
> Amiga OS program at the same time.
I don't think that's my quote.
I've got a board that plugs into a 5150 (as a
display adapter) and
takes the MDA display and combines it with RS-232 data coming in
from an external system and formats the display as split-screen on a
VT220 terminal (the board also plugs into the 5150's keyboard port).
There's no software that comes with the board--all of the smarts are
on the board in the form of a Z80 sharing display RAM with the 5150.
I'm not sure I understand how you'd use this...
Were there any good reason any of the coprocessor
boards for the
Apple ][ couldn't have been time-sliced with the main 6502?
Time-sliced how? To alternate displaying the output of one processor,
then the other on the primary display? I did have a Spartan Mimic
that was, in effect, a bolt-on Apple II for the C-64. You could
hot-key one CPU or the other to be displaying, but it was done with
relays to physically switch the video out of one processor or the
other to your monitor. I was able to play two Infocom games
simultaneously with that rig - type one command, then switch CPUs
while the first CPU ground on the disk for a few seconds. Very handy
for game research (not so handy for really _playing_).
-ethan