26 Nov
2010
26 Nov
'10
10:25 a.m.
On 11/26/2010 2:03 AM, jim s wrote:
Do you recall any of the people at Microdata you worked with. I can name
such as Max Malone, Al Weber, Chuck Canon.
Hmmm, I don't think I ever actually
talked to anyone at Microdata. The
computer selection and company interface process all happened at a
higher level than I was involved with at the time.
The 821 firmware became the 1621, 1630, and later. I wrote and have a
Disk system we called MPS that was written at the University of
Missouri, Rolla for the 1621. We had a 5mb dynex drive, 2.5mb removable
over 2.5mb fixed which the system ran on. It was very similar to CPM,
but actually modeled after CPS on the IBM mainframe, and TSO.
Interesting. We
never had any "standard" peripherals interfaced to
ours. Ours was truly an "embedded" controller. If it had been a few
years later, I'm sure we would have used a Motorola 6800 or similar.
Another group in the company was already using the Fairchild F8 in a
product, but I think it was felt the F8 could not meet the processing
requirements.
I still have the software and firmware, and have an emulator I have been
working on to run the1621 code. I'd be interested if your friend with
the diode boards still has any notes or materials from the firmware
project.
I'm afraid I've completely lost touch with him, and I was not
involved
with his project at all. At the moment I can remember his first name
but not his last. Since you say 1621 emulator I'm assuming you mean the
higher level code and not the microcode. Isn't it interesting with
these machines how one must specify the code "level". I'm sure there
are other examples of this, but I've never personally encountered it
other than with the Microdata machines. BTW, I've always had a pipe
dream of replacing the 800 microcode board with one containing RAM.
That would open up some interesting possibilities I think!
I have an 810 firmware in diodes. The diode boards run in both the 800
and the 1600.
I'm pretty sure I have at least one discrete diode 820 firmware
board as
well. I did not know the 1600 would run the same microcode. I assume
from that fact that the low level architecture in the
1600 is the same
or possibly a super set of the 800's.
As to your friend, the other thing that was interesting was that the
micro assember would not only give you the object tape out, but it would
give you a map of where to populate on the board, and a diode count if
you wanted it to.
I'm guessing the micro assembler ran on a 360?
I don't think I got the fortran cross assembler, or cross micro tools,
but there was also a simulator on which you could do some checkout, all
in fortran. The simulator on the mainframe was not interactive at the
time, and not very useful.
It has been a very long time, but I seem to recall the
820 assembler I
started with was written in Fortran ?? to run on an IBM 360. For a
variety of reasons we needed it to run on a Datacraft 6024. For one
thing, though the accounting department had a 360 it did not have a
paper tape punch peripheral. (I suppose I could have "punched" to mag
tape on the 360 and then done a mag tape to paper tape copy on the 6024,
but there were other issues as well.) I really doubt that I have the
source of the 820 assembler. If I do, it is probably only on a mag tape
which has been in the garage a lot of years. I *might* possibly have a
hard copy listing of the Fortran source code. I'm sure I don't have the
punched card deck that was my working source.
There was one written which ran on the 1600 that was interactive, and a
bit more useful. Sim1600.
I never used a simulator for the 820. For development
purposes we had
an ASR33 interfaced to the 820 and a small debugger that lived at some
dedicated place in core memory. The debugger could also load the
application from a higher speed paper tape reader.
Jim