UTEC
Beatrice Helen Worsley and Perham Stanley, two graduate students working at the Computation Center, were sent to Cambridge University to work with Maurice Wilkes who was in the process of completing the EDSAC. Worsley wrote the program that generated a table of squares, the first program to successfully run on EDSAC.
Another two graduate students, Alf Ratz and Josef Kates had been studying circuitry for some time by this point, and turned their attention to computer memory systems. Their first attempts were with a novel system based on neon tubes, but a 1949 visit by Freddie Williams led to them abandoning this work and moving to Williams tubes instead.
Given the current level of funding a full-scale machine was not possible, so it was decided to build a smaller machine to test out the various components. Williams tubes would store 256 12-bit words, with instructions using 3-bits of a word leaving 9-bits for addressing (allowing up to 512 words of memory).
Parts of the machine were up and running quickly, with the math and logic units (the arithmetic logic unit in modern terminology) running by the autumn of 1950. Memory reliability proved to be a serious problem, as it was for all systems using the Williams tube concept, but Katz introduced shielding that improved things somewhat. The machine was declared fully operational on October 1, 1951.
Over the next few months major efforts were made to increase reliability, as well as add a second bank of memory to bring it to the full 512 words. Libraries added math functions for 12-, 24-, 36- and 48-bit math. A basic 12-bit addition took about 240 microseconds, multiplication about 18 milliseconds.
With the basic system up and running, attention turned to a "full sized" version. This machine would use a 44-bit word with 1,024 words of memory backed up with a 10,000 word magnetic drum to be supplied by Ferranti Canada. A new math unit would operate on an entire word in parallel, instead of bit-serial as with most machines of the era, dramatically improving performance so that an addition would take only 20 microseconds and a multiply about 200 -- faster than the prototype at addition even on its much smaller word size.
Success of the UTEC created intense demand within the Canadian research establishment to start construction of the full scale follow-on. The funding pool was increased to $300,000 to cover development and construction.
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