[TUHS] C from 1980 binaries

[Clem Cole via TUHS]

Indeed. Great guy.  The Unix community stop solidly on his shoulders for
many years.  I haven't spoken to him in years.  After the CalData lawsuit
and when he created Able, he said he'd only make peripherals and swore off
CPUs.   His DMAX (DH/DM) became pretty much required if you were part of
USENET, particularly if you had Telebit Modems.   He made a lots money
selling them to the Unix community.  He knew it was very appreciative.   He
used to come to USENIX conferences regularly and warn us to watch out about
Unibus implementations from a number of the 3rd party vendors.  Which with
him being one himself, was humorous.

Besides his famous replacements for DEC's terminal mux products, he also
made bus repeaters and caches.  At an early USENIX shortly after he had
released a cache for the 11/34, a couple of us were at dinner and I was
sitting next to him.  In those days, besides being a Unix hacker,  I was
also designing hardware and had just designed the MMU for the Tek
Magnolia.  So I asked Ken, since he was moving the Unibus memory down
stream of his cache, why couldn't put a new MMU in it, and basically NOP
the DEC MMU, but split 22-bit adresses out the other end.  We sketched
something and he said he would think about it.

About a month or two later he calls me and asked if I wanted to try what he
just finished.  They ended up calling it the "Enable" and allowed 11/40 and
11/45 class systems to address up to 4M like the 11/70.  If you google it,
you'll find Noel's page on Gunkies.  Noel also has links to the paper I
wrote about it, as well as scan of the prepublication user manual and a
sketch of the registers it supported whicj I had sent Noel a few years
ago.  The code is actually still 2.11BSD but disabled since it's no longer
relevant as 2.11 pretty much requires an 11/70 and boards are hard to find
these days.

BTW, a few years later Mike O'Dell and I tried to get him to make a version
on the DMAX for the ISA or EISA bus.   We also suggested making an Ethernet
version with a 68000 in it and we would wrote the code for it, since
putting serial ports, particularly ones with modems, on PC hardware was
such a losing proposition. But Ken told us that margins for PC peripherals
was too low for him make any money on it.

Soon there after we all bought Livingston boxes to do the job.  I always
felt bad, as I think would have done a great job if could have figured it
out.

BTW: he did eventually break his rule about CPUs slightly. He ended up
creating a QBUS 68010 CPU board that he showed me when I visited him in
Irvine at some point.  I don't know how well it sold and lost track of him
after that as I left the Vax/PDP-11 world and when I returned to it to work
on Alpha, I never ran into him.


Sent from a handheld expect more typos than usual

On Sun, Nov 1, 2026 at 9:11 PM Jon Forrest via TUHS <tuhs at tuhs.org> wrote:

>
>
> On 11/1/26 5:13 PM, Clem Cole via TUHS wrote:
>
> > At the time, WD was working on the chipset, and DEC had won the lawsuit
> it
> > filed against California Data Processors (*a.k.a.* CalData). The results
> of
> > that lawsuit were fresh in the eyes of the team at WD  [Ken O'Mohundro
> and
> > Fred Cox's firm cloned a number of different ISAs but chose the UNIBUS,
> > which got them in trouble.  O'Mohundro had famously run the complete
> 11//40
> > diagnostics suite for Ken Olson at the National Computer show in
> CalData's
> > booth].
> Ken O'Mohundro - there's a name I haven't heard in a while. In the early
> 1980s I ran the Santa Barbara VMS Users Group. At the time, there were a
> few vendors who were starting to make DEC-compatible peripherals, such
> as memory, and disk/communication/network controllers. One of the
> vendors was Able, in Orange County, CA. Somehow Ken contacted me to
> ask if he could come talk to our users group about DEC stuff. Ken
> was a self-described stutterer who enjoyed addressing groups of
> people as a form of speech therapy. So, he came all the way up
> to Santa Barbara from Irvine and gave a nice presentation. IIRC,
> Able Computer paid for lunch for everyone.
>
> He was a very nice guy.
>
> Cordially,
> Jon Forrest
>
>