15 Apr
2024
15 Apr
'24
10:57 a.m.
On Mon, Apr 15, 2024 at 12:53 AM Christopher Zach via cctalk
<cctalk(a)classiccmp.org> wrote:
Was reading the Wikipedia article on Drum memories:
https://en.wikipedia.org/wiki/Drum_memory#External_links
And came across this tidbit.
As late as 1980, PDP-11/45 machines using magnetic core main memory
and drums for swapping were still in use at many of the original UNIX
sites.
Any thoughts on what they are talking about? I could see running the
RS03/RS04 on a 11/45 with the dual Unibus configured so the RS03's talk
to memory directly instead of the Unibus, but that's not quite the same
as true drum memory.
Yep.
Closest thing I remember was the DF32 on a pdp8 which
could be addressed
by word as opposed to track/sector.
Yes. And the RF series (RF08 and RF11).
UNIX on the PDP-11 in 1972 required an RF11 for swap. As mentioned in
other replies, the media isn't cylindrical but it behaves logically
like a drum.
-ethan