Core rope memory is a form of read-only memory (ROM) for computers, first used in the 1960s by early NASA Mars probes and then in the Apollo Guidance Computer (AGC) designed and programmed by the MIT Instrumentation Lab and built by Raytheon.
Contrary to ordinary coincident-current magnetic core memory, which was used for RAM at the time, the ferrite cores in a core rope are just used as transformers. The signal from a word line wire passing through a given core is coupled to the bit line wire and interpreted as a binary "one" while a word line wire that bypasses the core is not coupled to the bit line wire and is read as a "zero". In the AGC, up to 64 wires could be passed through a single core.
Software written by MIT programmers was woven into core rope memory by female workers in factories. Some programmers nicknamed the finished product LOL memory, for Little Old Lady memory.
Read more about Core Rope Memory: Memory Density
Famous quotes containing the words core, rope and/or memory:
“The threadbare trees, so poor and thin,
They are no wealthier than I;
But with as brave a core within
They rear their boughs to the October sky.
Poor knights they are which bravely wait
The charge of Winter’s cavalry,
Keeping a simple Roman state,
Discumbered of their Persian luxury.”
—Henry David Thoreau (1817–1862)
“I love him who does not want to have too many virtues. One virtue is more virtue than two, since it is more knot on which to hang the rope that is destined to hang him.”
—Friedrich Nietzsche (1844–1900)
“In memory everything seems to happen to music.”
—Tennessee Williams (1914–1983)