Right, I had found it there right after Doug's refresh of my memory. Many thanks to you both.

I grab a copy and put it in my own historic archives.

Clem

http://bitsavers.org/pdf/regnecentralen/RC_4000_Reference_Manual_Jun69.pdf

On Sat, Mar 9, 2019 at 3:03 PM Bakul Shah <bakul@bitblocks.com> wrote:

On Sat, 09 Mar 2019 14:19:43 -0500 Doug McIlroy <doug@cs.dartmouth.edu> wrote:
> Clem,
>
> I think the "Algol machine" you have in mind is the RC-2000 (not quite sure
> of the designation--could look it up in the attic if it matters) designed by
> Per Brinch Hansen for Regencentralen (again, the name may not be quite right).

I believe he architected and wrote the OS for RC-4000.

> The manual used Algol as a hardware description language. The instruction
> set was not unusual. It has come up before in TUHS. I have the manual
> if you need more info.

This manual is at bitsavers.