The Pilot ACE computer was built at the National Physical Laboratory in England from 1946 to 1951, based on a design by Alan Turing. While intended merely as a testbed for a full-scale “Automatic Computing Engine”, it was one of the fastest computers of its time, running at a bit clock rate of 1 MHz.
Turing came up with a minimalist computer design, a bit-serial architecture which could be implemented with less than 800 vacuum tubes. The computer was designed around ultrasonic delay line memory: Program instructions and data were stored as trains of ultrasound pulses which travelled through mercury-filled tubes. It essentially knew only one operation – a data transfer from a source to a destination address. Arithmetic and logic operations, as well as branching, were implemented via dedicated source and destination addresses which performed the required functions.
I built a scaled-down functional model of the Pilot ACE. The “Tiny ACE” uses simple integrated logic circuits and real ultrasonic delay line memory. I am working on a project description and on cleaning up the project schematics and source files, to be shared here soon. In the meantime, a few teaser photos below…
New – Recently I presented the Tiny ACE at the Vintage Computing Festival in Berlin. For German speakers, here is the poster from my exhibit and a link to the recorded presentation.