[TUHS] Can PDP-11/23 PLUS run Unix?

[segaloco via TUHS]

On Thursday, February 26th, 2026 at 15:06, Madeline Autumn-Rose via TUHS <tuhs at tuhs.org> wrote:

> v7m is also an option
> Sent from my iPhone
> 
> > On Feb 26, 2026, at 15:03, Clem Cole via TUHS <tuhs at tuhs.org> wrote:
> >
> > https://gunkies.org/wiki/PDP-11/23#:~:text=hampage.hu,are%20no%20problems%20with%20this.
> >
> >
> > To your questions. Because it lacks separate I/D
> > Space and does not support supervisor mode (only user and kernel) 2.11BSD
> > will not work.  However V6 and V7 are possible. I think Ultrix-11 should be
> > able to work and is more likely to have the low level details that 11/23
> > will need.
> >
> >
> > Sent from a handheld expect more typos than usual
> >
> >
> >> On Thu, Feb 26, 2026 at 5:52 PM ROBERT MYERS via TUHS <tuhs at tuhs.org> wrote:
> >>
> >> I’ve just obtained a 11/23 Plus system off of EBay and plan to get a QBone
> >> to emulate memory along with a few other things.  I need to know if
> >> Floating Point support is a requirement as well if I can also emulate up to
> >> 4 Mb of memory.  I’m interested in v6/v7/BSD2.11 for Unix variants.
> >> Sent from my iPhone
> >>
> 
>

Here is a salient document:

https://www.tuhs.org/Archive/Documentation/Manuals/Unix_4.0/Volume_2/F.5.3_UNIX_on_the_PDP_11_34.pdf

Therein Ted Kowalski describes the process of moving UNIX from the
PDP-11/70 to the PDP-11/34, with mentions of the PDP-11/23 also being a
beneficiary of the porting efforts.  If there's not an out-of-the-box
solution already, this paper may be useful in re-porting V6, as would be
referring to Mini-UNIX and LSX, both of which are in the UNIX tree.

- Matt G.