July 9, 2010 AT 5:53 pm

Fast Forward: Core Memory

mmmm… ferromagnetic core…

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  1. haha, core memory is fast because it has so much sugar! 😀

  2. deliciously memorable!!

  3. delicious!!

  4. Wow! Thanks for that flash back. 😉

  5. Mom! Dad ate my science project, again! – Bart Simpson

  6. It was really cool back in the day to flip the power on your PDP-11 and have it pick up right where it left off.

    As he mentioned, they never found a way to mechanically mass produce it – core was all made by people (mostly women) with microscopes and tiny sewing needles.

    One other fun fact he left out – the only way to read core memory is to erase it (if the erase operation produces a signal on the sense line, you had a one, otherwise it was zero. Special circuitry had to write back the value back to the core immediately after it was read.

  7. Actually, one of my Grandmother’s jobs was threading core memory. My mom seems to think she worked at Honeywell.

  8. We had some core memory back in my college days. It was just an interesting historical item, I don’t think it actually worked any more and we certainly had nothing to connect it to.

    £1,000,000/mb when it first appeared. Of course no-one actually used a whole megabyte of it, it was just used as a sort of “cache” for fast data processing and was often supplemented with slower barrel or delay line memory.

  9. The gentleman in this clip is David Stringer. After this show (Fast Forward), he went on to do a TV Ontario show called “The Acme School of Stuff”.

    Acme School had a hands on approach to science education. Stringer’s willingness to take anything apart — and his corny sense of humour — where both pretty inspiring to my ten-year-old self.

    Stringer’s posted more shoestring-budget educational goodness at: http://www.youtube.com/acmeschool

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