On Fri, 7 Oct 2022, Chuck Guzis wrote:
I recall that the IBM 650 had an upgrade option where core was used for some of the registers. It was small--maybe 50 words.
The Z22 had a very small area of core memory, called "fast memory" (Schnellspeicher). And then we have boards out of an LGP-21 (that we still lack in our collection) that replaced the on-disc registers with semiconductor shift registers. I don't really know why they did that.
Christian
