10 ms·
I picked up a beautiful 4096 bit (64x64) core plane on eBay a few years ago: https://geary.com/images/CoreMemory.jpg https://geary.com/images/CoreMemory.jpg Z
by Stratoscope 8y ago
I picked up a beautiful 4096 bit (64x64) core plane on eBay a few years ago:
https://geary.com/images/CoreMemory.jpg https://geary.com/images/CoreMemory.jpg
Zoom all the way in to see the detail of this 512 bytes of hand woven memory. Later core planes were machine woven; this was from an early '60s Burroughs machine.
The original image above is 8MB, so here are reduced size versions that load faster, use whichever works best for you...
https://www.flickr.com/photos/geary/46893923024/ https://www.flickr.com/photos/geary/46893923024/
https://geary.smugmug.com/Computers/History/i-jb2rgF5/A https://geary.smugmug.com/Computers/History/i-jb2rgF5/A
- commandlinefan 8y agoHow big is that? The writing suggests that it could fit in the palm of your hand - I actually expected it to be a lot bigger.
- Stratoscope 8y agoFunny you ask, I was looking for the board to measure it - and then I realized I could just count the pixels! I made the photo by scanning the board on my Brother MFC with a 1200 DPI scanner. The image is just shy of 6000x6000 pixels, so that makes the board about 5" square.
- commandlinefan 8y agoWow, those magnets are really tiny!
- Stratoscope 8y agoAround the same time I bought that core plane, I bought a bag of bits from someone in eastern Europe: a little ziplock bag with about 512 loose ferrite cores of this same size. Yep, that's 64 bytes in a baggie! It is pretty cool to see loose bits like that. But if you think these bits are tiny, they got a lot smaller when they went to machine weaving. Maybe half or quarter this size. Of course, "tiny" is relative, isn't it? At least you can see these bits, not like your newfangled semiconductor memory.
- eigenloss 8y agoYou can see those with a microscope (or at least an SEM) pretty easily.