[Simh] MagicSix
Phil Budne
phil at ultimate.com
Fri Nov 9 21:35:22 EST 2018
> Has there been any attempt to locate the operating system MagicSix
Larry Stewart wrote:
As far as bits go, I don't have any, although I do have some
hand-drawn schematics of the color display I built for the
Interdata model 85 and my old undergrad thesis (color printing).
Andy Lipman forwarded my query to Gregory Steve & Paul Mockapetris
with the prefix "Any ideas for this poor soul?"
Paul Mockapetris wrote:
I have a few shards of the Magic operating system somewhere, but
not nearly enough to make anything interesting run. I don't know
if there's any history or photos from the era. If anyone has any,
I'd love to get them.
My recollection of the history is that Nicholas forbade any OS
work. So naturally, while he went off for a summer in Patmos, we
built one.
Alternatively, since the Architecture machine was not famous or
funded enough at the time, the resources we had were a limited
amount of CPU time donated by the IBM Cambridge Scientific Center,
some Interdata minicomputers, and a hard drive.. So as I remember
it, Steve Gregory and I started some software, while Andy and
perhaps Mike did the disk controller and shared I/O bus. We
called the system Magic for Mockapetris and Gregory's Interactive
Computer, since we couldn't build an operating system
Magic 1.0 allowed basically a user per machine with a shared fail
system.
While ludicrous by today's standards, it was probably state of the
art at the time. We could easily have published in the computer
science journals of the time, if only we had known we were being
cool rather than practical.
I remember Jim Taggart had some software he was working on that he
would keep on multiple paper tapes of source code, then debug and
accumulate paper tapes of patches, and then go back and redo the
source and rebuild. The editing and compiling and linking meant a
new build from source would take a couple days or more. Once we
had Magic working, Jim could rebuild in 40 minutes or so, mostly
with his feet up as the system grinded away. He was our biggest
defender when Nicholas came back from Patmos. (I also seem to
remember a huge sigh of relief when we got the ability to back up
the Magic disk drive to mag tape, after I had been backing it up
illicitly to an IBM timesharing system via a terminal emulation a
scheme at 15 or so characters per second)
I believe this was the summer of 69 or maybe 70. I was off after
that,
Anyway, I remember that this stone age stuff was replaced by
bronze or iron age versions. I seem to recall Magic 6.0 with 32
bit architecture and a PL/1 compiler, but somebody else will have
to tell that story.
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