On Mon, Apr 15, 2024 at 12:53 AM Christopher Zach via cctalk <[email protected]> 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
