Cores in space: The core memory module from a 1980 Spacelab computer
38 points by pwg 3 hours ago | 7 comments

kens 2 hours ago
Author here for all your core memory questions...
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Zigurd 29 minutes ago
No special provisions for rad hardening needed?
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kens 15 minutes ago
Core memory is very resistant to radiation. When the Shuttle computers were upgraded to semiconductor memory, radiation became an issue. The solution was to add six extra bits of storage to each word and use ECC. A background process scanned for errors and corrected them. The computer could encounter 100 bit flips per flight, so radiation was significant. (There was even an incident where a single cosmic ray flipped 14 bits.) The other problem with semiconductor memory was its volatility, so the computer had NiCd batteries for backup power to the RAM.

For details on how radiation affected the Space Shuttle's computers, see this paper: https://klabs.org/DEI/Processor/shuttle/oneill_94.pdf

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iberator 2 hours ago
Please write an article about that French computer Project idea: find 64kb kb of such memory and connect it somehow into Apple2, atari and other 8bit cpus hehe

It must be possible to have some hardware adapter to map RAM into that type of memory.

Or even over serial...

ps. Related story: around 10 years ago Texas Instruments started to use FRAM in some of their 16 bit MCUs (msp430 family)

It works exactly like core memory - data still intact after power resets.

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kens 2 hours ago
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userbinator 54 minutes ago
FRAM is a somewhat common retrofit for battery-backed SRAM: https://bastelblog.runlevel3.de/en/restore/ds1250-fram-repla...
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annoyingnoob 19 minutes ago
Built by highly skilled humans.
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