Re: NetBSD without MMU ?

[John Clark <j1clark%ucsd.edu@localhost>]

Am Freitag den, 12. April 2002, um 10:28, schrieb Greg A. Woods:

> [ On , April 12, 2002 at 12:27:58 (-0400), Perry E. Metzger wrote: ]
> > Subject: Re: NetBSD without MMU ?
> >
> > MINIX uses the x86 segment registers to much the same purpose as an
> > MMU.
>
> I don't know that I'd call the way MINIX uses the 8088 segment registers
> as "base registers" really that much of an MMU-like function, though I
> guess in comparison to something without any such feature (like maybe a
> 6502) it is a form of memory managment -- but it's not a separate MMU
> (tightly or loosely coupled) -- its integrated into the programming
> model of the main CPU.

Gosh, and just last weekend I finally let go of my 6502, 8080, Z80, and
8086/88, 286 programmer's manuals... along with some vintage discreet
transistor data in suggestive positions...

However, wasn't one of the early Santa Cruz Operation unices such
that it could run on something other than a 286. But this is so ancient
I am very hazy on just what it was... At the time I did implement a
Douglas Comer like real time scheduler which ran on top DOS 3...

But I digress...