[TUHS] Are various DEC UNIXes targeted to address space and/or Floating Point implemented?

[Larry McVoy via TUHS]

Well then go for it.  I wouldn't mind being in front of an actual PDP-11
all these years later.  I'm 64, my PDP-11 days are 40 years ago but I
remember those days very fondly.  It was a great machine, big enough
and small enough.

I fish on the ocean on a boat that is described the same way, I have
a big small boat or small big boat.  It's good enough in much the same
way the PDP-11 was good enough, you could run a multi user Unix on a 64KB
(and banks and I think you got to 256KB?), I fish on the ocean in my boat,
got a 157 pound bluefin this year (been chasing that for 3 years, finally
got one).  It's a small but capable boat, pretty much like the PDP-11.

The fact that Unix worked, multi user, on such a small machine is amazing.
Huge credit to Dennis and Ken and team making things small, that is a lost
art, my browser, one tab, has 37GB virtual, 5GB real.  That's one tab.
Don't get me started about slack, it's just as bad.

We are a long way from PDP-11 unix, you want to go run that, go you.

On Tue, Nov 03, 2026 at 07:15:24PM -0600, ROBERT MYERS wrote:
> My problem with this is that the build scripts for windows and visual studio haven???t been brought up to date for Windows 11 and Visual Studio 2026.  I also have to come up to speed with GitHub,  cmake, and any other requirements to build under this environment.
> 
> Since I have the 11/83 and 11/23+ machines, there is I believe Unix v6 targeting a 11/73 emulation (going from memory; had to remove a hard drive & controller as my 11/83 is in a questionable state right now).
> 
> 
> Sent from my iPhone
> 
> On Nov 3, 2026, at 6:55???PM, Larry McVoy <lm at mcvoy.com> wrote:
> 
> ???On Tue, Nov 03, 2026 at 06:12:34PM -0600, ROBERT MYERS via TUHS wrote:
> > 
> > I have a 11/83 with floating point and a 11/23+ that I haven???t determined if it does.  Both have 22 bits of address space.  Both will have either a QBone or QBone Duo module.
> > 
> > Any issues with running Various Unixes on them?  I know the 11/83 has 4Mb of PMI memory and the 11/23+ will have emulated memory of up to 4Mb.
> 
> Other than "just because it is cool", wouldn't running whatever on a
> simulator work just as well and run faster?  
> 
> Don't get me wrong, I learned assembler on a PDP-ll, Kendall Witte is who
> I'm pretty sure was my TA, the instruction set was so well thought out,
> he could come over, crack open a beer, look at the octal dump of what I
> was running and read it like it was the assembler.  Made a big impression
> on me, that's a very clean instruction set.  This crowd probably all
> knows, but the PDP-11 instruction set sort of did everything in a way
> that you could read it in an octal dump, there were patterns and the
> patterns didn't vary.
> 
> I also loved the PDP-11 because it gave me a mental model of what a
> computer is that I use to this day.  Yeah, computers today are way more
> complex, but the basic model still holds true.  Can any of you imagine
> showing someone x86 and saying "see, that's a computer" and expect anyone
> to have a mental model they can reason about?
> 
> I liked the National 320xx series as well, it seemed like it was trying to
> be a modern PDP-11 but they never worked the bugs out and it went nowhere.
> The 680xx seemed like it was actually a modern PDP-11 but I didn't get
> the sense the instruction set was as clean as the PDP-11, Clem or anyone
> care to comment?

-- 
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Larry McVoy           Retired to fishing          http://www.mcvoy.com/lm/boat