out-of-mainstream minis

[Mattis Lind]

2015-07-02 16:02 GMT+02:00 Paul Koning <paulkoning at comcast.net>:

>
> > On Jul 2, 2015, at 1:31 AM, tony duell <ard at p850ug1.demon.co.uk> wrote:
> >
> > Not all minis came from the States :-)
> >
> > One of my favourite non-mainstream families is the Philips P800 series.
> It's
> > a 16 bit machine with 16 registers (0 is the program counter and 15
> > is the stack pointer, rest are mostly general purpose) and separate
> > I/O instructions (not memory-mapped I/O).
>
> Another Philips machine, probably still more obscure, is the PR8000.  I’ve
> been looking for documentation about it, with no luck whatsoever.  I wrote
> up a partial description, from memory and from looking at some old
> listings.  It’s a 24 bit machine, with 8 sets of 8 registers (memory mapped
> like the PDP-10).  For each interrupt level there’s a set of registers, so
> at interrupt time no register saving is needed.  Neat.
>

That remind me of the the Norsk Data ND-10  (Maybe the ND-1 and ND-100 is
the same in this aspect) which is a 16 bit machine with 16 different
interrupt levels. Each interrupt level has its own set of registers. On top
of that it also have a memory protection scheme with four different
protection levels.

Nord-10/S front panel:
https://dl.dropboxusercontent.com/u/96935524/Datormusuem/Nord10.png

/Mattis


>
>         paul
>
>
>