Yeah, I'm pretty sure it was your picture of the "business system" that I
saw.
My understanding is that the interface between the Altair 8800 and the HDC
was by way of a parallel port arrangement. What was never clear to me was
whether or not there actually was an OS for that system. Did they (Or
anyone else) have a CP/M for it? If so, which MITS serial I/O board was
used as the default channel for the console? Which MITS board provided the
parallel I/O?
It happpens that I have a CP/M boot diskette and some listings, etc,
associated with an Altair using a Morrow DJ2 FDC. It uses a MITS serial I/O
board which is as good as any, I guess, as a model.
please see additional remarks below.
Dick
----- Original Message -----
From: "James Willing" <jimw(a)agora.rdrop.com>
To: <classiccmp(a)classiccmp.org>
Sent: Thursday, January 04, 2001 10:49 PM
Subject: Re: Altair Owners ...
At 08:37 PM 1/4/01 -0700, Dick wrote:
>As I've often heard, Altair had the reputation that nothing they ever
>shipped worked as shipped, often either requiring one pay for a service
of
modifying it at
the plant before it was shipped, or to fix it or have it
fixed once it had arrived. From a historical perspective, an Altair that
actually works is an anomaly. That explains why they're all different.
I tend to think that these reports are somewhat overblown, as I had (and
still have) an early Altair as well as most of the other major Altair
models in the collection, and built a number of others in my jobs in the
early days and never had the types of problems that I seem to keep seeing
recounted. And all of my machines still run quite happily. Heck, I had
the 'B' unit running MITS Timeshared BASIC at VCF 3.0
>Nevertheless, after the passage of some time and the addition of a number
of
>vendors to the S-100 market which grew out of the
Altair, it was possible
to
>purchase, from MITS, a complete Altair computer
system that was packaged
in
a sort of
half-desk, with a rackmount pedestal at one end in which the
computer hardware lived.
The MITS/Pertec "Business System"
I remember asking about this system here on the
list about three years back, and found that someone actually had a pretty
good picture of it on their website.
Well, I have a picture on my web site although not the greatest shot.
It apparently used a CDC Hawk drive
Ummm... no. It used a Pertec 5mb cartridge hard drive.
However, if you want to talk stories... I did have CDC 'Hawk' drives
running on S-100 boxed running CP/M via an AM-500 controller. Then at the
flip of a switch and change of a cartridge you could boot up AMOS on the
Alpha-Micro AM-100 CPU that lived along side of the Z-80 CPU board in the
box.
>interfaced via this Altair Hard Disk Controller, the box for which is
what
>I'm messing with, and it used an 8800B, and
the Altair Floppy Disk Drive
I
>once owned. It's the functional philosophy of
the finished and complete
>Altair system that I'm interested in preserving, if that's warranted, and
>I'm beginning to believe it's a waste of effort. It's apparent from
what
>I've gotten from this thread so far, that attention to detail such as
that,
>and providing self-installing drivers for CP/M
would be a waste of time,
and
would not
increase the practical or economic value of this hardware one
iota. Perhaps making it all work would simply reduce its appeal.
One point of view... From my side, I prefer running systems. B^}
>It's likely everyone in this forum is aware that the 1975 Altair was
totally
useless.
(donning the flame retardant suit) It's "likely" that this view would
represent those who came into the 'personal computer' realm after 1980
when
most of the hard work had already been done. I found
my 1976 Altair *far*
from useless, even though it had no I/O beyond the front panel switches
and
lights, and a total of 4k of memory. It was an
invaluable learning tool.
Unfortunately, few folks took time to do the learning.
>It had no I/O, no software, no nothing that held out any hope of
>making it useful. The only thing it did have is potential. The miracle
>that Ed Roberts pulled off, ultimately involving Bill Gates, among
others,
>is in recognizing that there were so many people
out there who'd buy
light
>blinkers and buzzers, etc, just to be playing with
electronics. There
were
>already computers. Some of them were pretty
expensive, and the Altair
was
>no cheapie either, particularly since it really
didn't work, even after
you
fixed it, since
work was an undefined quantity for a CPU with no I/O.
So, from this statement I take it anything that was not 'ready to fly' was
worthless? Seems like one heck of an industry grew from a pile of
'useless' stuff. Altairs, AIM-65's, Scelbi's, the Mark-8, etc... All
of
which started with limited resources and little to no I/O.
First of all, there's a HUGE difference between "little" and
"no" I/O. What
I mean is that if it has a keypad and a display, or, for that matter, a
front-panel with switches and LEDs, it still can't do much. However, if you
add a serial or parallel I/O port, things take on a different hue, since you
now can communicate with another intelligent (or dumb) device.
There's no comparison at all, say, between an AIM-65 and an Altair. The AIM
not only has text I/O but it provides the means to load and save externally
stored software. It has software tools including a debugger, assembler, and
a BASIC interpreter, and it has quite enough I/O hardware to do quite a bit
of useful work, and it has enough resources to make its capabilities
comparable to Intel SBC's costing thousands more.
Having said that, the Altair certainly held out a promise of things to come.
It's that potential that was exploited by so many people to create the
situation we have today. Whether we like where we've gotten, well, that's
another story.
>The real miracle, however, was in turning the potential into something
real,
>namely software. The I/O wasn't the real
problem. The absence of
software
was the problem
and we all know who fixed that.
Yes... The early hobbiests and tinkerers who saw the potential. Gates
and
Co. did nothing revolutionary.
No, they did nothing that hadn't already been done at DEC and Intel.
However, they did it so it could be sold to the masses, which was not what
Intel and DEC wanted to do.
Once that problem was addressed, the rest was
pretty automatic, as the
demand pressed the missing pieces in to existence.
And created the painful commodity item that the masses are stuck with
today. (sigh)
Yes, but it did keep them off our welfare roles, didn't it? They were,
after all, (meaning Bill G. & associates) mostly college drop-outs. The
goal, after all, was to produce better living for them, and not necessarily
ideal computing for us.
-jim
jimw(a)agora.rdrop.com
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