[Andy Geppert] sends in his incredibly clever interactive core memory shield.
In a great display of one hacker’s work being the base for another’s, [Andy] started out with [Jussi Kilpelainen]’s core memory shield for Arduino. As he was playing with the shield he had a desire to “see” the core memory flipping and got the idea to add an LED matrix aligned behind the individual cores.
The first iteration worked, but it only showed the state that the Arduino believed the core memory to be in. What he really wanted was a live read on the actual state. He realized that an Adafruit Featherwing 8×8 matrix display also fits behind the core memory. Now the LEDs update based on the read state of the core memory. This allows him to flip the individual bits with a magnetic stylus and see the result. Very cool.
You can see a video of it working after the break.