Archived posting to the Leica Users Group, 2015/10/20
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Larry, If you?re local to the Computer History Museum, maybe we can meet there some time. I?ve been volunteering there since about 2003 or whenever it was that they moved from Moffat Field to the ex-Silicon Graphics building. I?m a docent, and do the talking part of the Babbage Engine demo at 1 pm on almost every Saturday. Herb Herbert Kanner kanner at acm.org Question Authority and the authorities will question you. > On Oct 20, 2015, at 12:25 PM, Larry Zeitlin via LUG <lug at > leica-users.org> wrote: > > 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 > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information >