[Info-vax] OT: IA-128 ???

[P. Sture]

In article 
<d19d4a6b-e7a0-47bc-b337-be2de56ba0ab at l9g2000yqi.googlegroups.com>,
 BillPedersen <pedersen at ccsscorp.com> wrote:

> PDP-11/45, the second generation of PDP-11 was also a 16 bit processor
> but it had a MMU to access up to 18 bits, so you could have 256KB of
> memory, less the 8KB IO space.
> 
> PDP-11/70 introduced a MMU which was separated from the Unibus and
> provided up to 22 bits memory addressing.  It was STILL at 16 bit
> processor.

Thanks Bill, I remember mention of 18 bits and 22 bits on an RSX course.

We had an 11/34 with (IIRC) 192KB memory and running RT-11. It was with 
great satisfaction that I took out a load of overlays once we got the 
memory upgrade.

-- 
Paul Sture