[Leica] Babbage Difference Engine

[lrzeitlin at aol.com]

 Herbert,From Wikipedia’s article on magnetic core memories:
"Two key inventions led to the development of magnetic core memory in 1951. The first, An Wang's, was the write-after-read cycle, which solved the problem of how to use a storage medium in which the act of reading erased the data read enabling the construction of a serial, one-dimensional shift register of o(50) bits, using two cores to store a bit. A Wang core shift register is in the Revolution exhibit at the Computer History Museum. The second, Jay Forrester's, was the coincident-current system, which enabled a small number of wires to control a large number of cores enabling 3D memory arrays of several million bits e.g. 8K x 8K x 64 bits.”  So I guess we are both right.


Now back to the Leica S. A toy for the very rich.


Larry Z