You've got to be pulling my chain... (Ethernet) - test-drb@ccmp.vtda.org

11 Apr 1998

On Apr 11, 23:08, Tony Duell wrote:
...
   Some versions
and OS vaiations allowed a 2KW IO space.  I've run RT-11
 that way. 
 Yep, you're right. The standard on Unibus machines was for a 4kW I/O
 space. I've seen PDP11/45's and PDP11/34's that were modified for 2kW I/O
 space, and, indeed, undone the mods. Some Q-bus machines had 2kW I/O
 space as standard, I think. 
The 11/03 is the most notable one with a 2KW I/O space, but that's a mod, not
the standard.  Quit commonly done, though, because it was only 16-bit address.

...
  Didn't the 11/24 have an optional unibus map card
(the KT24?) I've never
 seen one - my 11/24 is a pretty minimal configuration. 
Yes, I've got one, and it is indeed 22-bit.  The problem is, I only have the
board set, not the backplane, front panel, etc.  I have a spare backplane, and
I once inrtended to rewire it and build a panel, but never found enough info
(the second slot is wired to the first in a non-standard way, to accomodate the
Unibus map connections).

-- 

Pete						Peter Turnbull
						Dept. of Computer Science
						University of York