Converting ENIAC

Abstract

In spring 1947 a project was launched to convert ENIAC to run code written in the new from introduced with the 1945 “First Draft of a Report on the EDVAC.” This was intertwined with the planning of Monte Carlo calculations for Los Alamos. Adele Goldstine worked with a team of contractors led by Jean Bartik and a group of Aberdeen employees under Richard Clippinger to develop a succession of planned “set-ups” to implement a new control mechanism and vocabulary of general purpose instructions for ENIAC. Our analysis focuses particularly on the relationship of this work on concurrent efforts by von Neumann’s team on the design of the Institute for Advanced Studies computer and a series of related reports on programming methods. Accounts by participants and historians have differed dramatically in assigning credit for the conversion and on such basic facts as when the conversion was implemented and what version of the design was used. The conversion was finally implement in March 1948 by Nick Metropolis (of Los Alamos and the University of Chicago) using a variant design he formulated with Klara von Neumann. At this point ENIAC became the first computer ever to execute a program written in the “modern code paradigm.”