Great looking conference room art — framed core memories!
This was the industry standard for electronic memory before DRAM and SRAM and Flash. Data was stored in the magnetization, or not, of each ring. It is a non-volatile memory, and relatively immune to radiation and soft errors, much like MRAM today.
Many of the rectangular patches are 4K bits. The early ones were woven by hand, and over the years the iron ring sizes shrank and became tightly woven into an electromagnetic fabric.”
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.