The original version of that was the Dimond ring translator for #5 crossbar.[1] The purpose of this device was to translate a line position in the switching system to the phone number for billing purposes. It was a big ROM which could be manually changed by moving wires. This allowed some phone number portability - if you moved within the same central office area, you could keep the same phone number.
It shows how hard it was to make a memory device in the 1950s. For a long time, that was the bottleneck in computing. Electronic arithmetic units date from around 1940, but memory devices that didn't suck only came in around 1965, and didn't get cheap until around 1990.
It shows how hard it was to make a memory device in the 1950s. For a long time, that was the bottleneck in computing. Electronic arithmetic units date from around 1940, but memory devices that didn't suck only came in around 1965, and didn't get cheap until around 1990.
[1] http://etler.com/docs/Crossbar/articles/30-AMATranslator.pdf