Innovative Ideas & Stepping Stones Part II
Innovative Ideas & Stepping Stones
Necessity is the mother of invention. But not all her offspring end up equally successful.
Computer engineers recognized the need for efficient, reliable, affordable memory and storage. Many devised solutions, often attracting supporters who invested considerable money and time. Some ideas worked. Others fizzled, yet served as valuable stepping-stones to later technologies. And many, ultimately, proved creative dead ends.
Plated Wire Memory
Bell Labs began developing this variation on core memory in 1957. Straight wires had separately magnetized areas. Unlike traditional core memory, it could be machine assembled instead of hand-wired. The Viking Mars lander and Hubble Space Telescope used plated wire memory.
This plated wire memory was used in an improved US Minuteman III missile computer.View Artifact Detail
Nixdorf Rod Cell Read-Only Memory
Also called “magnetic stick” memory,” this technology featured a board studded with 144 vertical rods of wire coil. If one of its 256 hand-threaded wires went around a rod, it represented a “one.” Threaded past a rod, it represented a “zero.”
Card Random Access Memory (CRAM)
Mylar magnetic cards, each holding 21,700 characters, were assembled in “files” of 256 cards. Notched edges enabled individual cards to be individually selected and wrapped around a spinning drum. Failure—not uncommon—produced a spectacular mess and destroyed data.
IBM Data Cell Drive
Seven years in the making, IBM’s 1964 Data Cell Drive stored up to 400 MB. Wide magnetic strips were plucked from bins and wrapped around a rotating cylinder for reading and writing.
Reliability problems plagued the initial release, but after improvements it was used until 1976.
The Data Cell Drive was announced in 1964 with the System/360 mainframe computer. Allstate Insurance used one to store insurance policies.View Artifact Detail
Card Capacitor Read-Only Storage (CCROS)
The IBM System/360 Model 30 used CCROS to store microcode. It was a capacitor memory that could be programmed by punching holes in its Mylar card with a standard keypunch.
The microcode stored in this memory was used in IBM Models 50 and 65 mainframe computers to provide compatibility with other models in the System/360 family.View Artifact Detail