Qbus split I&D?

Johnny Billquist bqt at update.uu.se
Mon Mar 16 14:15:25 CDT 2015

On 2015-03-16 19:51, Noel Chiappa wrote:
>      > From: Johnny Billquist
>      > I need to see if I can locate the manual in the summer when I get close
>      > to where I had that 11/34
> That would be wonderful, if you find it! In addition to showing for sure how
> it basically worked, I still also have a number of questions as to exactly
> how it connected up to the optional cache, EUB memory, etc.
>      > we still seem to talk about two different ENABLE products, though... :-)
> I saying what I'm about to say, I am not in any way trying to be
> argumentative (truly, I would be as happy if you were correct, just as much
> as if I were, _provided that we had found out what the correct answer really
> is_), but I really do think that your memory is playing tricks on you, with
> the 'it didn't require any software changes at all'.
> The "Enable/34" described in contemporary posts here:
>    http://gopher.quux.org:70/Archives/usenet-a-news/FA.unix-wizards/81.07.09_ucbvax.2202_fa.unix-wizards.txt
>    http://gopher.quux.org:70/Archives/usenet-a-news/FA.unix-wizards/81.07.12_ucbvax.2254_fa.unix-wizards.txt
> works the way I'm describing... (Although note I do think Mike made some
> mistakes in the diagram in the first one - I think the DMA devices have to be
> behind the ENABLE/34, per his description in the second post of how it works.)
> I wish we could find a copy of the paper mentioned there ("Modifications to
> UNIX to Allow Four Mega Bytes of Main Memory on a 11/40 Class Processor" by
> Clement T. Cole and Sterling J. Huxley), as it might also answer the questions
> I have...

Noel. All I can say is that I did a number of RSX SYSGENs on that 11/34, 
and it truly looked just like an 11/24 from a software point of view.
I wish I had some more details at hand, but all I have are my 
recollections (but anyone who have done an RSX-11M SYSGEN or three knows 
that you do not forget them lightly).
I'm hoping that Update (the computer club) still have the documentation 
around. I know we had the manuals when I played with the machine in the 
early 90s.


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at softjar.se             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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