Engineering "The Miracle of the ENIAC": Implementing the Modern Code Paradigm

In 1947 John von Neumann had the idea of converting ENIAC to the new style of programming first described in his celebrated "First Draft of a Report on the EDVAC." By April 1948, Nick Metropolis, building on plans developed by Adele Goldstine and others, had implemented the conversion, making ENIAC the first computer to execute programs written in the new style, which we call the "modern code paradigm." Treating this as a case of user-driven innovation, the authors document the conversion process and compare capabilities of the reconstructed machine to those of the first modern computers. This article is the second in a three-part series. The first article, "Reconsidering the Stored Program Concept" (published in IEEE Annals, vol. 36, no. 1, 2014; http://doi.ieeecomputersociety.org/10.1109/MAHC.2013.56), examined the history of the aforesaid idea and proposed a set of more specific alternatives. The third, "Los Alamos Bets on ENIAC: Nuclear Monte Carlo Simulations, 1947-1948" (to appear in IEEE Annals, vol. 36, no. 3, 2014; http://doi.ieeecomputersociety.org/10.1109/MAHC.2013.56), will examine in detail the first program run on the machine after its conversion to the new programming method.