Another rule

By adding a few more colors and a few more rules, the circuits can get simpler. The additional colors and rules are almost a change in detail. A red cell was triggered to turn white by one or two neighbors. Then it would pass through a blue refractory state before falling back to red. The new colors and rules mimic this. A gray cell can be triggered to turn yellow by two or three neighbors. It'll then pass through a magenta refractory state before turning gray again.

The new rules allow for a simpler diode. Two red cells beside a gray cell are all that it takes. An electron coming in from the two red cell end can trigger the gray cell. An electron coming in from the one gray cell end is simply blocked. Use step to see this in slow motion.


Diodes exist in the world of electronics. They first appeared the the days of vacuum tubes. A vacuum tube diode consisted of an evacuated bottle with two signal wires leading in. One wire connected to a flat plate of metal, the other to a sharp needle a small distance away from the plate. The theory of operation was that electrons could easily jump from the point to the plate but had a harder time jumping from the plate to the point.


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Brian Silverman
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