It computes the Fibonacci sequence!
I finally got my prototype to do a real calculation: computing the Fibonacci sequence F(n) = F(n-1) + F(n-2). Started with 1 and 1, the sequence is 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377,... Here's a still image after it just computed 233, and here's a video of it computing all the numbers from 2 to 377. (The resolution is poor because Blogger has a 100MB limit on videos.) It's running at the full "Babbage speed" of 157 milliseconds per digit. I consider this my first real milestone! There are three phases to the computation, assuming F(n) is on digit wheel A1, F(n-1) is on anticipating carriage wheel F, and digit wheel A2 is zero. add A1 to F, while simultaneously preserving A1 by copying it to A2. move F to A1 move A2 to F Repeating that generates the Fibonacci sequence on A1. Here's the detailed microcode: //**cycle 1: add A1 to F while simultaneously copying it to A2 "finger A1; mesh FC; mesh MPC A1; mesh FPC A2; keepers up; unlock F del...