[TUHS] core

[Ronald Natalie]

> 
> 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.