
Emulating the AT&T 3B2 Computer - mmastrac
https://loomcom.com/2018/05/22/emulating-the-att-3b2-computer/
======
kabdib
I had a 3B2 in the 1980s; it was an okay Unix machine that AT&T had no idea
how to market. The development tools (C compiler, etc.) cost extra, and came
on about 30 floppy disks that you had to load in a very fussy order. The
machine's black-and-white user interface was, well, _terrible_ , and the
documentation had been written by out of control PM/marketing types (you
didn't press a button, you "touched" it. You "touched" everything in the UI;
this oddball wording, and affectations, permeated the manuals and dialog
boxes).

Right: But hey, _real Unix_!

I got Emacs and GCC and uucp/netnews/email working, but when it came to
developing something on the 3B2, it turned out that programming Macintoshes
was a lot more fun, and certainly paid better.

One day its 67MB hard drive made a groaning noise and a thin, straight trail
of smoke rose up from it. I walked across my office and turned the 3B2 off,
and didn't shed a tear.

~~~
MarkMMullin
The "touch" button thing was a big deal back then - Apple and others kept
reminding devs that is was not a good idea to tell users to "hit" keys as
sometimes this was taken a little too literally :-)

~~~
zenojevski
What's wrong with "press"?

~~~
kabdib
That's what everybody else uses. If you want to write edgy, hip and modern
documentation you need to use words that other people don't. "Touch" implies a
friendly, approachable and non-threatening user interface. It lets your boss
know that you're all-in with this edgy new Unix UI stuff.

tl;dr: It's marketing bullshit.

The UI on the 3B1 was definitely nothing to write home about . . .

------
joezydeco
The CS program at UIUC in the 1980s had a pile of 3B2s in the programming
labs. The "intro to assembly language" weedout course was taught on the
WE32100 processor. I think the architecture class also did some primitive gate
simulation on the Blit terminals.

It wasn't a bad chip. The C language integration was really understated here.
It's the only chip I've ever seen with a strcpy() opcode. Totally dangerous
now, pretty wild back then.

~~~
flyinghamster
Yup, I remember those very well. The course, IIRC, covered both assembler and
C. Teaching myself 6502 assembler back in my high school/junior college days
helped me a great deal, even though the 6502 was vastly more limited.

I later did some 8086 assembler in my first job as well, mainly some routines
for testing a QIC tape drive.

~~~
joezydeco
Mad props if you spent weekends in the Woodshop trying to make your MPs
compile. Nice to see a fellow Illini around.

And yeah, there was C in that class too. Mostly enough to make sure you
understood pointers so that you could get into the homework and shoot yourself
in the foot repeatedly.

It was one of my favorite classes during my time there. I also had some 6502
experience which helped. But I think CS225 solidified the idea of "either
you're going to understand this for the rest of your life, or you're not.
Choose now."

~~~
felixgallo
The best part was when they gave an entire class of 250 CS students one
ancient Pyramid to compile their C code on. Compile times of 30 minutes and
more for hello world were not unheard of. Thanks UIUC.

~~~
joezydeco
I was on that Pyramid too. uxa.cso.uiuc.edu for life, yo.

The key was having some kind of terminal and modem back at the dorm so you
could log into the system after the labs were closed. You literally had the
entire machine to yourself all night long. =)

~~~
felixgallo
I managed to sneak onto uxb and uxc. My modem was for PLATO avatar and empire.
:)

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Animats
But Lucent already has a 3B2 emulator.[1] It's used to run MERT and DMERT,
real-time operating systems used by central office phone switches for
auxiliary functions.

[1] [https://en.wikipedia.org/wiki/Multi-Environment_Real-
Time](https://en.wikipedia.org/wiki/Multi-Environment_Real-Time)

~~~
lnx01
My guess is that:

1) It's not open source / FOSS

2) According to the linked article, laced with bugs

3) Only runs on SPARC

edit:

4) Not using SIMH

~~~
krylon
> Only runs on SPARC

Oh, come on, you can emulate a SPARC using qemu! ;-)

~~~
trasz
Or with the TME emulator
([https://people.csail.mit.edu/fredette/tme/](https://people.csail.mit.edu/fredette/tme/)).

~~~
krylon
Thank you so much for mentioning that!

------
Diederich
Story time!

In 1994, I was a 3C0X2 in the USAF (Air Force), 'Computer Programmer', at the
81st Medical Support Group, in Biloxi Mississippi. Curiously, I had more
experience with general UNIX administration than anyone else in my unit, so I
was in charge of the UNIX servers in the basement of the hospital where I
worked.

There were at least 10 different UNIX variants there, including the (even at
that time) venerable 3B2. We had a couple of them handling some 'lightly'
classified ('SECRET') data.

They weren't quite enough, so we put the word out that we needed more. My OIC
(Officer In Charge) took care of 'putting the word out'; I didn't really know
what that meant.

A few months later, a crate arrived on our loading dock, and inside were
probably a dozen 3B2s! They had come from Homestead AFB, Florida.

You might recall that
[https://en.wikipedia.org/wiki/Hurricane_Andrew](https://en.wikipedia.org/wiki/Hurricane_Andrew)
had blown through there two years earlier, and destroyed the base.

All of the servers had clear signs of submersion. As in, there were old algae
stains on the cases. Two of them had been partly submerged, since there was a
straight line across the center, apparently a high water mark.

Being young, crazy, enlisted and bold, we decided to give them a try. So we
found a long, heavy extension cord and ran it out to the parking lot next to
the loading dock, and plugged them in, along with a required external serial
terminal.

Much to our surprise, most of them booted up just fine! One of them started
smoking, so we unplugged it.

In the end, after a lot of outside 'burn in' time, we were able to mount four
in our datacenter and begin using them for classified data processing.

~~~
Aloha
I collect vintage telephone equipment - I've seen much 40+ year old hardware
that still works without trouble, the build quality for AT&T/Western Electric
hardware was amazing - so none of this surprises me.

~~~
Diederich
Yup. Re: the 3B2s, I don't know how much they cost at the time, but I heard
that they were extremely expensive. Everything was, of course, but the AT&T
hardware especially.

------
creeble
We did a port of AutoCAD to the 3B2 in... 1987?

By that time, Sun 3s(?) were our development platform, so it was relatively
easy. But it was quite the dog.

But hey, _real UNIX_ , whatever that was!

------
anthk_
That computer was used at sdf.org. Some Linux "smart" people suggested to
switch to Intel and Linux. The system got uber exploited. Then, they switched
to NetBSD under Alpha. No issues registered until today.

------
mchahn
My company had an IO device ATT wanted to support on the 3B2. I got to visit
their lab and work with them for a few days. They were a bunch of great guys
who really believed in what they were doing.

------
ibiza
For some reason "Frasier Crane" preferred the 3B2, and had one in his sound
booth for many years. This seems a rather contrarian choice given his locale.

[https://goo.gl/images/niRdtU](https://goo.gl/images/niRdtU)

~~~
enf
That doesn't look like a 3B2. Maybe an AT&T 6300.

------
kinsomo
Maybe there's some practical use for this: it looks like 3B computers are
still used in some AT&T POTS telephone switches:

[https://en.wikipedia.org/wiki/5ESS_Switching_System#Administ...](https://en.wikipedia.org/wiki/5ESS_Switching_System#Administrative_Module)

[https://en.wikipedia.org/wiki/No._4_Electronic_Switching_Sys...](https://en.wikipedia.org/wiki/No._4_Electronic_Switching_System#File_store_and_CNI_ring)

~~~
Aloha
The only thing the 3B2 and the 3B20/21 have in common is the CPU
Microarchitecture, they're very very different beasts.

------
mrbill
The very first "real UNIX box" I owned was a PC7300/3B1. Got it working with
the built-in 1200 baud modem and everything.

Eventually replaced it with a Sun 3/50, but I have fond memories of the 3B1
(and there are great emulators for it).

------
KWxIUElW8Xt0tD9
Blast from the past, I did a lot of work on 3B2/600's at Bell Labs back in
85-93...

UNIX on Amdahl and VAX 11/785 those were the days.

