by Nyles Heise

- A. K. Dewdney

for introducing me to WireWorld with his Scientific American article in 1990 and for writing "The New Turing Omnibus", from which I took many ideas for these designs. - Karl Scherer

for his great work in WireWorld design. Karl's web site has a voluminous amount of devices from basic elements to complex multipliers. Some of these devices have been used here. Karl and I have also recently cooperated is coming up with some more-compact versions of the 4-cycle logic I devised in 1990. The free games page to Zillions of Games contains a downloadable, operational file that allows you to watch WireWorld in action. - Ed Pegg, Jr.

for hosting MathPuzzle and including WireWorld updates on the web site. - Mirek Wojtowicz

for developing and supplying, FREE, MCell and MJCell. - Mark Owen

for his marvelous WireWorld computer. In addition to the overall machine, there are lots and lots of amazing gadgets throughout the design. With his permissiong I'm making available the .mcl version of the computer here. - My wife, Bev

for allowing me to spend the time to ... Wait, this isn't the Oscars. Let's just get on with it.

WireWorld is the famous 2-D cellular automaton created by Brian Silverman in 1987. It was basically presented to the world by A. K. Dewdney in the 1990 issue of Scientific American.

The beauty of WireWorld is that the basic concept is easy to understand, but mastery of design is difficult.

So here's WireWorld. Rectangular grid, each cell is one of 4 states.

- Background, always background
- Wire, changes to Electron Head if 1 or 2 of its 8 neighbor are Electron Heads
- Electron Head, always changes to Electron Tail
- Electron Tail, always changes to Wire

From of this definition, logic circuits (and a whole lot more) can be built. I will not not talk much about the well-known designs, but present my 4-tick logic gates and more complex machines. A good source of WireWorld devices can be found at Karl Scherer's Web Site.

I give the designs as gif's or jpg's, but also use the MJCell applet to allow you to watch the devices run. The basic logic gates and some of the smaller machines work well with the applet. The larger machines can be viewed nicely with MJCell, but don't expect them to run to completion. To run the large machines download the mcl files from this web site and run with Mirek's Cellebration. MCell a marvelous, free program. That's right. Marvelous. And Free. All the designs presented here run well in MCell.

My excursions into WireWorld started by reading Mr Dewdney's article in the 1990 issue of Scientific American. I devised 6-tick logic elements, and, after a few sleepless nights, 4-tick methodology. My letter to Mr. Dewdney, which he mentioned in the March issue, was converted into HTML format and is included here.

Many of the basic 4-tick logic gates are presented. Some of these were available in 1990. Others have been recently redesigned to fit into a more compact area. The methodology is the same as in 1990. Some of the new layouts were done by Karl Scherer.

This is the smallest logic gate possible in WireWorld. Guaranteed!

Several versions of 4-tick binary multipliers are given. The design is a offshoot of the work done by Brian Trial, Nick Gardner, and most notably, Karl Scherer.

This is a famous 2D Turing machine. It was the first of several Turing machines I designed.

Ed Pegg Jr. has devised a slight modification to the Langton's Ant rules that makes our ant do a binary count.

Here is a Turing machine that does not have a central control mechanism. It does a binary copy, as given in Karl Scherer's Zillion's Turing Machine.

A Turing machine of the first type that does a "big" multiply of 5x8.

Some 3-tick gates, including a very small latch.

A Wireworld implementation of the train set so elegantly espoused by the Tweedle's, Dum and Dee. Actually what's given is a Unary Multiplier (1) in a Turing Machine (2) in a Train Set (3) in WireWorld (4). The highest level of indirection I will attempt.