Editing Von Neumann architecture (section)

==Development of the stored-program concept==
The mathematician [[Alan Turing]], who had been alerted to a problem of mathematical logic by the lectures of [[Max Newman]] at the [[University of Cambridge]], wrote a paper in 1936 entitled ''On Computable Numbers, with an Application to the [[Entscheidungsproblem]]'', which was published in the ''Proceedings of the London Mathematical Society''.<ref name="Turing1936">{{Citation |author-last=Turing |author-first=Alan M. |author-link=Alan M. Turing |publication-date=1937 |date=1936 |title=On Computable Numbers, with an Application to the Entscheidungsproblem |periodical=Proceedings of the London Mathematical Society |series=2 |volume=42 |pages=230–265 |doi=10.1112/plms/s2-42.1.230|s2cid=73712 }} and {{Citation |author-last=Turing |author-first=Alan M. |author-link=Alan M. Turing |publication-date=1937 |title=On Computable Numbers, with an Application to the Entscheidungsproblem. A correction |periodical=Proceedings of the London Mathematical Society |series=2 |volume=43 |pages=544–546 |doi=10.1112/plms/s2-43.6.544 |date=1938 |issue=6}}.</ref> In it he described a hypothetical machine he called a ''universal computing machine'', now known as the "[[Universal Turing machine]]". The hypothetical machine had an infinite store (memory in today's terminology) that contained both instructions and data. [[John von Neumann]] became acquainted with Turing while he was a visiting professor at Cambridge in 1935, and also during Turing's PhD year at the [[Institute for Advanced Study]] in [[Princeton, New Jersey]] during 1936–1937. Whether he knew of Turing's paper of 1936 at that time is not clear.

In 1936, [[Konrad Zuse]] also anticipated, in two patent applications, that machine instructions could be stored in the same storage used for data.<ref>{{citation |title=Electronic Digital Computers |journal=Nature |date=September 25, 1948 |volume=162 |page=487 |doi=10.1038/162487a0 |df=mdy-all |last1=Williams |first1=F. C. |last2=Kilburn |first2=T. |issue=4117 |bibcode=1948Natur.162..487W |s2cid=4110351 |doi-access=free }}.</ref>

Independently, [[J. Presper Eckert]] and [[John Mauchly]], who were developing the [[ENIAC]] at the [[Moore School of Electrical Engineering]] of the [[University of Pennsylvania]], wrote about the stored-program concept in December 1943.
<ref name="Lukoff_1979">{{cite book |author-last=Lukoff |author-first=Herman |author-link=Herman Lukoff |title=From Dits to Bits: A personal history of the electronic computer |date=1979 |publisher=Robotics Press |location=Portland, Oregon|isbn=0-89661-002-0 |lccn=79-90567}}</ref><ref>ENIAC project administrator Grist Brainerd's December 1943 progress report for the first period of the ENIAC's development implicitly proposed the stored program concept (while simultaneously rejecting its implementation in the ENIAC) by stating that "in order to have the simplest project and not to complicate matters", the ENIAC would be constructed without any "automatic regulation".</ref> In planning a new machine, [[EDVAC]], Eckert wrote in January 1944 that they would store data and programs in a new addressable memory device, a mercury metal [[delay-line memory]]. This was the first time the construction of a practical stored-program machine was proposed.  At that time, he and Mauchly were not aware of Turing's work.

Von Neumann was involved in the [[Manhattan Project]] at the [[Los Alamos National Laboratory]]. It required huge amounts of calculation, and thus drew him to the ENIAC project, during the summer of 1944. There he joined the ongoing discussions on the design of this stored-program computer, the EDVAC. As part of that group, he wrote up a description titled ''First Draft of a Report on the EDVAC''<ref name ="FirstDraftReport"/> based on the work of Eckert and Mauchly. It was unfinished when his colleague Herman Goldstine circulated it, and bore only von Neumann's name (to the consternation of Eckert and Mauchly).<ref>{{Harvnb|Copeland|2006|p=113}}.</ref> The paper was read by dozens of von Neumann's colleagues in America and Europe, and influenced{{vague|date=March 2022}} the next round of computer designs.

[[Jack Copeland]] considers that it is "historically inappropriate to refer to electronic stored-program digital computers as 'von Neumann machines{{'"}}.<ref>{{Citation |author-last=Copeland |author-first=Jack |author-link=Jack Copeland |title=A Brief History of Computing: ENIAC and EDVAC |date=2000 |url=http://www.alanturing.net/turing_archive/pages/Reference%20Articles/BriefHistofComp.html#ACE |access-date=2010-01-27}}.</ref> His Los Alamos colleague [[Stan Frankel]] said of von Neumann's regard for Turing's ideas<ref>{{Citation |author-last=Copeland |author-first=Jack |author-link=Jack Copeland |title=A Brief History of Computing: ENIAC and EDVAC |date=2000 |url=http://www.alanturing.net/turing_archive/pages/Reference%20Articles/BriefHistofComp.html#ACE |access-date=2010-01-27}} (a work which cites {{Citation |author-last=Randell |author-first=Brian |author-link=Brian Randell |title=On Alan Turing and the Origins of Digital Computers |editor-last=Meltzer |editor-first=B. |editor-last2=Michie |editor-first2=D. |page=10 |place=Edinburgh |publisher=[[Edinburgh University Press]] |journal=Machine Intelligence |volume=7 |date=1972 |isbn=0-902383-26-4}}.</ref>
{{quote|
I know that in or about 1943 or '44 von Neumann was well aware of the fundamental importance of Turing's paper of 1936....
Von Neumann introduced me to that paper and at his urging I studied it with care. Many people have acclaimed von Neumann as the "father of the computer" (in a modern sense of the term) but I am sure that he would never have made that mistake himself. 
He might well be called the midwife, perhaps, but he firmly emphasized to me, and to others I am sure, that the fundamental conception is owing to Turing—in so far as not anticipated by Babbage.... Both Turing and von Neumann, of course, also made substantial contributions to the "[[reduction to practice]]" of these concepts but I would not regard these as comparable in importance with the introduction and explication of the concept of a computer able to store in its memory its program of activities and of modifying that program in the course of these activities.
}}

At the time that the "First Draft" report was circulated, Turing was producing a report entitled ''Proposed Electronic Calculator''. It described in engineering and programming detail, his idea of a machine he called the ''[[Automatic Computing Engine|Automatic Computing Engine (ACE)]]''.<ref>{{Harvnb|Copeland|2006|pp=108–111}}.</ref> He presented this to the executive committee of the British [[National Physical Laboratory, UK|National Physical Laboratory]] on February 19, 1946. Although Turing knew from his wartime experience at Bletchley Park that what he proposed was feasible, the secrecy surrounding [[Colossus computer|Colossus]], that was subsequently maintained for several decades, prevented him from saying so. Various successful implementations of the ACE design were produced.

Both von Neumann's and Turing's papers described stored-program computers, but von Neumann's earlier paper achieved greater circulation and the computer architecture it outlined became known as the "von Neumann architecture". In the 1953 publication ''Faster than Thought: A Symposium on Digital Computing Machines'' (edited by B.&nbsp;V. Bowden), a section in the chapter on ''Computers in America'' reads as follows:<ref>{{Harvnb|Bowden|1953|pp=176, 177}}.</ref>
<blockquote>
'''The Machine of the Institute For Advanced Study, Princeton'''

In 1945, Professor J. von Neumann, who was then working at the Moore School of Engineering in Philadelphia, where the E.N.I.A.C. had been built, issued on behalf of a group of his co-workers, a report on the logical design of digital computers. The report contained a detailed proposal for the design of the machine that has since become known as the E.D.V.A.C. (electronic discrete variable automatic computer). This machine has only recently been completed in America, but the von Neumann report inspired the construction of the E.D.S.A.C. (electronic delay-storage automatic calculator) in Cambridge (see p. 130).

In 1947, Burks, Goldstine and von Neumann published another report that outlined the design of another type of machine (a parallel machine this time) that would be exceedingly fast, capable perhaps of 20,000 operations per second. They pointed out that the outstanding problem in constructing such a machine was the development of suitable memory with instantaneously accessible contents. At first they suggested using a special [[vacuum tube]]—called the "[[Selectron tube|Selectron]]"—which the Princeton Laboratories of RCA had invented. These tubes were expensive and difficult to make, so von Neumann subsequently decided to build a machine based on the [[Williams tube|Williams memory]]. This machine—completed in June, 1952 in Princeton—has become popularly known as the Maniac. The design of this machine inspired at least half a dozen machines now being built in America, all known affectionately as "Johniacs".
</blockquote>

In the same book, the first two paragraphs of a chapter on ACE read as follows:<ref>{{Harvnb|Bowden|1953|p=135}}.</ref>
<blockquote>
'''Automatic Computation at the National Physical Laboratory'''

One of the most modern digital computers which embodies developments and improvements in the technique of automatic electronic computing was recently demonstrated at the National Physical Laboratory, Teddington, where it has been designed and built by a small team of mathematicians and electronics research engineers on the staff of the Laboratory, assisted by a number of production engineers from the English Electric Company, Limited. The equipment so far erected at the Laboratory is only the pilot model of a much larger installation which will be known as the Automatic Computing Engine, but although comparatively small in bulk and containing only about 800 thermionic valves, as can be judged from Plates XII, XIII and XIV, it is an extremely rapid and versatile calculating machine.

The basic concepts and abstract principles of computation by a machine were formulated by Dr.&nbsp;A.&nbsp;M. Turing, F.R.S., in a paper<sup>1</sup>. read before the London Mathematical Society in 1936, but work on such machines in Britain was delayed by the war. In 1945, however, an examination of the problems was made at the National Physical Laboratory by Mr.&nbsp;J.&nbsp;R. Womersley, then superintendent of the Mathematics Division of the Laboratory. He was joined by Dr. Turing and a small staff of specialists, and, by 1947, the preliminary planning was sufficiently advanced to warrant the establishment of the special group already mentioned. In April, 1948, the latter became the Electronics Section of the Laboratory, under the charge of Mr.&nbsp;F.&nbsp;M. Colebrook.
</blockquote>