On Fri, 7 Jun 2002, Brian Chase wrote:
> On Sat, 8 Jun 2002, Anders Magnusson wrote:

> > A PDP10 CPU normally have an address space of only 18 bits, which is
> > not enough to run something useable in. But the KL10-E have an "extended"
> > mode which give it the possibility to use 30 bit addressing, though
> > only 23 bits are used. The KL10-E were normally available in the
> > 2060 and 2065 systems.
>
> With the addressing, is that 23-bits of addressing to 36-bit words or
> 23-bits of addressing to 9-bit bytes?

With a little more sleuthing, I've managed to answer my question on that
one--it's word based. Also, it looks like the first extended addressing
mode processor was the KL10-B with the 23-bit limitation.  The Extended
Addressing doc I'm reading mentions the KC10 processor implementing the
full 30-bits of extended addressing--but that's apparently the designation
of the processor for the cancelled DEC Jupiter project.

Lars has a nice summary of PDP-10 processors on his site:
   http://pdp10.nocrew.org/cpu/processors.html

Documentation on Extended Addressing:
   http://zane.brouhaha.com/~healyzh/tops20_7/EXTENDED_ADDRESSING.HTML

-brian.