Computer Memories: A Survey of the State-of-the-Art

Computer memory developments of the last decade, the present state, and efforts for improvements are surveyed. The following topics are included: principles of storage and selection of random-access memories; principles and engineering considerations of current-coincident-driven core memories; magnetic decoding and load-sharing switches; word-organized one-core and two-core-per-bit memories; fast and impulse switching; transfluxor memories; non-destructive read-out memories; ferrite apertured plates; twistors; fixed read-only memories; thin magnetic film memories-dots, sheets, coated wires and rods; present operational memories typically with capacities of 105 to 106 bits and read-write cycles of 2 to 15 Msec; likelihood of the order of 100-nsec read-write cycle times attainable with ferrite and thin film memories; consideration relating to large capacities; ferroelectric memories attempts; cryoelectric superconductive memories¿principle, superconductive films, Crowe cells, continuous sheets, systems, and the outlook for large capacities; tunnel diode memories which promise a read-write cycle of the order of 10 nsec; and outlook for content addressable memories.