Edsac TG

Department of Computer Science, University of Warwick Coventry CV4 7AL, UK Edsac A Tutorial Guide to the Warwick University EDSAC Simulator by Martin Campbell-Kelly December 1995 © Martin Campbell-Kelly, 1990-95 The Cover The cover illustration shows an interactive computer game of Tic-Tac-Toe developed by a student programmer in 1952. To play the game, Load... OXO from the folder of Edsac demonstration programs. Enter your moves using the telephone dial. Edsac A Tutorial Guide to the Warwick University EDSAC Simulator Martin Campbell-Kelly Department of Computer Science University of Warwick Abstract The EDSAC was the world’s first practical stored-program computer; it was designed and built at Cambridge University, and performed its first fully automatic calculation on 6 May 1949. The Warwick University simulator is a faithful representation of the EDSAC designed to run on the Macintosh computer. The user interface has all the controls and displays of the original machine, and the system includes a library of original programs, subroutines, debugging software, and program documentation. This report includes a description of the EDSAC and an account of the seminal programming techniques developed for it during 1949-51. Several demonstration programs and programming problems are supplied, so that users can gain first-hand experience of what it was like to develop and run a program on a first-generation computer. Contents Before You Begin 4 1 Introduction and Orientation 5 2 EDSAC Architecture and Arithmetic 12 3 Programming the EDSAC 17 4 Debugging: Getting Programs Right 28 5 Problems from the Summer School and Elsewhere 32 Bibliography 33 Appendix of Tables 35 __________________________ © Martin Campbell-Kelly, 1990-95. Department of Computer Science, University of Warwick, Coventry CV4 7AL, United Kingdom. E-mail: mck@dcs.warwick.ac.uk. Revised December 1995. -3- Before You Begin: What the Papers Said In the late 1940s the EDSAC - and “electronic brains” in general - captured the public imagination and were widely reported in the press. Before you begin using the simulator you might like to read t…