[TUHS] core

Johnny Billquist bqt at update.uu.se
Mon Jun 18 15:58:56 AEST 2018

On 2018-06-18 04:00, Ronald Natalie <ron at ronnatalie.com> wrote:
>> Well, it is an easy observable fact that before the PDP-11/70, all PDP-11 models had their memory on the Unibus. So it was not only "an ability at the lower end", b
> That’s not quite true.   While the 18 bit addressed machines all had their memory directly accessible from the Unibus, the 45/50/55 had a separate bus for the (then new) semiconductor (bipolar or MOS) memory.

Eh... Yes... But...
The "separate" bus for the semiconductor memory is just a second Unibus, 
so the statement is still true. All (earlier) PDP-11 models had their 
memory on the Unibus. Including the 11/45,50,55.
It's just that those models have two Unibuses.


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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