29 Jun
2018
29 Jun
'18
7:16 p.m.
The recent reference to the Dennis's comments on ATT chip production had me
feeling nostalgic to the 3B line of computers. In the late 80's I was in
charge of all the UNIX systems (among other things) at the state university
system in New Jersey. As a result we got a lot of this hardware gifted to
us. The 3B5 and 3B2s were pretty doggy compared with the stuff on the
market then. The best thing I could say about the 3B5 is that it stood up
well to having many gallons of water dumped on it (that's another story,
Rutgers had the computer center under a seven story building and it still
had a leaky roof). The 3B20 was another thing. It was a work of
telephone company art. You knew this when it came to power it down where
you turned a knob inside the rack and held a button down until it clicked
off. This is pretty akin to how you'd do things on classic phone
equipment (for instance, the same procedure is used to loopback the old 303
"broadband" 50K modems that the Arpanet/Milnet was built out of). Of
course, the 3B20 was built as phone equipment. It just got sort of
"recycled" as a GP computer.
29 Jun
29 Jun
8:55 p.m.
You just pushed my "3B button". Rudd Canaday (who had a hand in the design
of the original UNIX file system) wanted to create a message-based
"Database Machine". We planned to base it on the MERT (Multi-Environment
Real Time) UNIX variant on VAXen, and had some of the architects of MERT on
the team with real expertise in VAX architecture. Unfortunately, just as we
were getting under way, the AT&T chip project needed clients, so we were
told "Thou shalt use AT&T computers". Not only did we have no expertise,
the documentation was almost non-existent, so the only way to learn was
trial and error. They installed two 3B20-ish computers that looked like
racks of telephone equipment (because that's pretty much what the were).
The first time we lost power in the computer room, and tried to bring
it/them back up, all the fuses blew. The AT&T techs looked astonished, and
asked if we lost power often (in a switching office, battery backups
ensured that power was never lost). We told them power went down every few
months. They showed us how to power things up by removing all the fuses,
then using a charging device (we called it the fuse-gooser) to charge up a
capacitor, insert a fuse, and repeat until all the fuses had been
reinstalled. Eventually, one of our people discovered an (undocumented, of
course) dial which could be used to ramp the voltage up from 0 to full, so
we didn't have to go through the fuse routine. "Production" versions of
the
3B20's had a lead-acid battery built in.
There was no floating point. (Why would a switch need floating point?).
There were things I wanted to do with awk that didn't need floating point,
so I just fiddled the code so AWKFLOAT was typedef-ed to int, and it darn
near worked. The only hitch was a couple of appearances of "%g" in print
statements. I couldn't typedef them away, but I suggested to the ANSI C
folks that I could have done that if the appearance of adjacent string
literals was treated as their concatenation, and they bought it. My only
contribution to ANSI C, courtesy of crappy hardware.
We were also gifted a 3B2. We brought it up single user, and it took 20
seconds to run a ps command. Our computers were theme-named after birds
(the 3B20 pair were heckle and jeckle), so we named the 3B2 junco. Our
director told us we couldn't do that, we had to play nice with the chip
folks. So we renamed it jay. But we all knew what the j stood for.
On Fri, Jun 29, 2018 at 9:16 AM, <ron(a)ronnatalie.com> wrote:
The recent reference to the Dennis’s comments on ATT
chip production had
me feeling nostalgic to the 3B line of computers. In the late 80’s I was
in charge of all the UNIX systems (among other things) at the state
university system in New Jersey. As a result we got a lot of this
hardware gifted to us. The 3B5 and 3B2s were pretty doggy compared with
the stuff on the market then. The best thing I could say about the 3B5 is
that it stood up well to having many gallons of water dumped on it (that’s
another story, Rutgers had the computer center under a seven story building
and it still had a leaky roof). The 3B20 was another thing. It was a
work of telephone company art. You knew this when it came to power it
down where you turned a knob inside the rack and held a button down until
it clicked off. This is pretty akin to how you’d do things on classic
phone equipment (for instance, the same procedure is used to loopback the
old 303 “broadband” 50K modems that the Arpanet/Milnet was built out
of). Of course, the 3B20 was built as phone equipment. It just got
sort of “recycled” as a GP computer.
9:07 p.m.
On Fri, Jun 29, 2018 at 10:55 AM, John P. Linderman <jpl.jpl(a)gmail.com>
wrote:
(we called it the fuse-gooser) to charge up a
capacitor, insert a fuse,
Yeah it was wild bit of mechanical design -- it pulled out on a small
rope/wire thingy. I used to say the 3B was the only computer I knew with a
'pull starter' like on a lawn mower engine.
ᐧ
10:31 p.m.
We were also gifted a 3B2. We brought it up single user, and it took 20 seconds to run a
ps command. Our computers were theme-named after birds (the 3B20 pair were heckle and
jeckle), so we named the 3B2 junco. Our director told us we couldn't do that, we
had to play nice with the chip folks. So we renamed it jay. But we all knew what the j
stood for.
Not unlike the “J” prefix in all the 5620 software, the last vestiges of the jab at PERQ
calling DMD predecessor the JERQ.
11:51 p.m.
ron(a)ronnatalie.com writes:
Not unlike the “J” prefix in all the 5620 software,
the last vestiges
of the jab at PERQ calling DMD predecessor the JERQ.
Oh... I guess this should have been obvious to me, but I had no idea
this is where the JERQ moniker came from. You learn something new every
day!
-Seth
--
Seth Morabito
https://loomcom.com/
web(a)loomcom.com
9:26 p.m.
ron(a)ronnatalie.com writes:
The recent reference to the Dennis's comments on
ATT chip production had me
feeling nostalgic to the 3B line of computers.
[...]
Oh I love hearing anecdotes about AT&T hardware. It should go without
saying that the 3B2, even with all its horrible flaws, is pretty special
to my heart, given all the effort I put into emulating it! I've learned
to really like the WE32000 architecture. It's just so well suited for
UNIX and C. It's a pity the clock speed was so slow, and that the
3B2/310 and 3B2/400 were so limited in memory. A 4MB maximum was not a
lot for a serious multi-user machine, even for 1985.
But, I have absolutely no experience with the 3B5 and 3B20. I would love
to hear more about them from those of you with experience. Were they
ever a marketing success? (And here, by marketing success, I mean as a
general purpose UNIX computer, not as a telephone switch)
Emulating a 3B5 or 3B20 would be fun, but I've seen even less internals
documentation about them than I have about the 3B2, so I fear it's a
hopeless task.
-Seth
--
Seth Morabito
https://loomcom.com/
web(a)loomcom.com
10:29 p.m.
My favorite 3B2ism was that the power switch was soft (uncommon then, not so
much now). I seem to recall that if the logged in user wasn't in a
particular group, pushing the power button was a no-op. You didn't have
sufficient privs to operate the power.
30 Jun
30 Jun
12:48 a.m.
On Fri, 29 Jun 2018 09:16:12 -0400 <ron(a)ronnatalie.com> wrote:
The recent reference to the Dennis's comments on
ATT chip
production had me feeling nostalgic to the 3B line of computers.
In the late 80's I was in charge of all the UNIX systems (among
other things) at the state university system in New Jersey. As a
result we got a lot of this hardware gifted to us. The 3B5 and
3B2s were pretty doggy compared with the stuff on the market
then. The best thing I could say about the 3B5 is that it stood
up well to having many gallons of water dumped on it (that's
another story, Rutgers had the computer center under a seven story
building and it still had a leaky roof).
We had huge numbers of 3B2s at Columbia that were gifted to us by
AT&T. They didn't know what to do with the things, so the undergrads
were subjected to using them for their labs for a few classes like
computer graphics. The blits attached to them were neat, though. If
only the same could have been said for the overall system.
The 3B20 was another
thing. It was a work of telephone company art. You knew this
when it came to power it down where you turned a knob inside the
rack and held a button down until it clicked off.
We had one of those donated, too. It was put into an extra machine
room and not used for very much, I think because the version of the
OS it came with didn't really do networking at a point where
everything else at the Columbia CS department did.
At one point we considered reusing its disk pack drives for some of
the Vaxes but unfortunately the cabling was incompatible.
Perry
--
Perry E. Metzger perry(a)piermont.com
2150
days inactive
2150
days old
7 comments
5 participants
participants (5)
-
Clem Cole -
John P. Linderman -
Perry E. Metzger -
ron＠ronnatalie.com -
Seth J. Morabito