View Full Version : Unix on an AT

April 3rd, 2017, 09:13 AM
If you were going to run Unix on an AT what flavor would you choose and why?

I don't have a lot of room in my apartment, my display table currently has my PC and Expansion Unit along with 5153 there, but I've been toying with the fact of loading up an AT that I got from the last haul to Glens Falls.

April 3rd, 2017, 09:19 AM
I would run Minix 2.04. With all the updates, its supposed to be very stable. And it would be period for that class of machine. The trick with Minix 2.04 is to get an extended memory card so you have more than 640K. Minix 2.04 will address the full 16 Meg memory but I've never seen it in actual practice. Here is the link: https://minix1.woodhull.com/mxdownld.html.

April 3rd, 2017, 09:20 AM
It looks like Minix 2 supports the 286, so I'd probably go with that. ELKS also has 16-bit support, and has been updated more recently, but I've always gotten the impression that ELKS is more of a project to cram Linux down into embedded systems than something seriously designed for lower-end hardware.

April 3rd, 2017, 10:08 AM
Is Minix real Unix or just a work-alike? There were real versions of Unix for the 80286.

April 3rd, 2017, 10:27 AM
Minix isn't real Unix, and it was never intended as a real-world OS, only an educational model, but still, it's the most useful Unix-like thing you can run on a 286.
It comes with TCP/IP, drivers for popular ethernet NICs, and C compiler.
In order to have all that in real Unices of that era, you had to purchase additional products, very hard to obtain now.
See also: http://www.vcfed.org/forum/showthread.php?55418-Modern-OS-for-16-bit-PC

April 3rd, 2017, 10:48 AM
There were real versions of Unix for the 80286.Really? :-)

Back around 1990 or so when I was working for the National Weather Service one of the computers we had was a Compaq 286 that ran Unix. It was always on and was responsible for multitasking six to eight programs simultaneously. Needlessly to say I was impressed! I still am. :-)

April 3rd, 2017, 10:48 AM
But there were Unices for the 80286. Much of the Unix kernel work was done at Intel while the 80286 was still being debugged. Xenix for the 80286 also existed. We were working with early steppings of the 80286 back then and bugging Intel with "When will you make an end?" and getting "When we are finished" as a response (obscure film reference).

Consider that when Unix for 80286 was released, there were very few NICs available. I'd venture that in 1984, most Unix boxes communicated via uucp and ftp over telephone lines (leased or otherwise). Sometime around then, I recall a friend who worked for one of the larger firms bragging that they had just acquired several Telebit Trailblazer modems.

This is, after all, a vintage board seeking to promote the vintage experience, no?

April 3rd, 2017, 08:43 PM
There is another Unix-like system for the 286 that deserves mention: Coherent 3. The documentation was excellent. It didn't support TCP/IP or IDE hard disks. But with the right scsi controller, it was rather polished. It has the same 64+64 limit. It also included its own UUCP and Compiler. I tested it once briefly but I don't have a 286 anymore. You can find it on the net now and I believe it was placed under a BSD license for non-commercial use.

April 5th, 2017, 08:40 AM
Main problem with Minix is that it only support tiny and small memory models. I think that Xenix is a better option, here you have a fairly complete kit to start:


You will find all this inside:

* SCO Xenix 2.3.2b for AT286/SCO
* Xenix x86 Development System 2.2.1a
* SCO Xenix Computer Graphics Interface 1.1.0d
* SCO Xenix On Line Manual Pages 2.2.0c
* SCO Xenix Text Processing System 2.2.0b
* SCO Lyrix 5.0.4a
* Microsoft Word 3.0
* Microsoft Multiplan 2.0
* Microsoft BASIC 5.41
* VS Cobol 1.2r7
* SCO FoxBASE 1.0