Stored Program Computer • RAM • 10 Print “HAL: I know SPC (Stored program computer quote from that you and Frank were Williams p. 302): planning to disconnect me, and I'm afraid • “it must be possible to erase the contents of that's something I the memory and store new data2 [JT: Stored Program Computers And cannot allow to happen”1 program instructions as well] in place of the • 20 If (Dave Bowman) old, then airlock crew • it must be possible to store information for Computer Memories member long periods of time; • it must inexpensive to construct because it would be needed in large quantities; This section includes developments in • it must be possible to get at the information being stored in very short periods of time early memory technologies as well as the Microsoft because there is no point in producing high- clipart speed electronic arithmetic and control units first stored program computers if you cannot get at the instructions and data with the same high speeds).” 1 “2001 Space Odyssey” © Warner Brothers, MGM James Tam James Tam 2 “An important feature of this device [JT: A stored-program computer] was that operating instructions and function tables would be stored exactly in the same sort of memory device as that used for numbers”1 Stored Program Computer? Stored Program Computer? • ABC? • Punch card and punched tape machines? •q w e r t y u i o p Input (decimal) •a s d f g h j k l Arithmetic z x c v b n m (binary) Output (decimal) A photo of Clifford Berry and the ABC, courtesy of Iowa state university Control: data and instructions (35 mm tape) •Capacitors James Tam James Tam Who Came Up With The Concept Of The Stored How Did Machines Receive Their Instructions Program Computer? • Before stored program computers • Why it’s important. – It’s a fundamental part of modern computers (and many, many other – (As mentioned) from tape or punched cards electronic devices: smart phones, smart devices etc.) – Hard wired connections (or before that redesigning and creating a • The answer whole new machine e.g. Pascaline, Difference engine etc.) – It’s shrouded in a great deal of controversy. • The location where the idea was developed – The Moore School (the team that developed the ENIAC) • The person most widely credited with coming up with the idea – John Von Neumann – He received so much notoriety that modern computers are sometimes referred to as “Von Neumann machines”. James Tam Image: Archives Center / Institute for Advanced James Tam Study (Shelby White and Leon Levy) Image: “A History of Computing Technology” (Williams) CPSC 409: Analog devices Who Came Up With The Concept Of The Stored Who Came Up With The Idea Of The SPC: Program Computer? (2) Optional External Video • Finally in 1947 a military lawyer made a ruling on the case • The original video shown in class includes a segment from this complete video – For the section pertinent to this section of notes starting watching around 19:23. The movie below includes additional footage from the court ruling ~22 minutes which provides good background and you can watch it until the end. – https://www.youtube.com/watch?v=pFP14xJmOdI&list=PL376DA99F15 341227&index=5 www.computermuseum.li Institute for Advanced Studies (IAS) James Tam James Tam www.computerhistory.org John von Neumann (1903 – 1957 ) John von Neumann (1903 – 1957 ): 2 • Born into a wealthy family in Hungary. • Privately educated until almost his teens (11). • At age 6: • He greatly impressed his teachers in the regular – Tell jokes in classic Greek. school system. – Memorize telephone directories on sight. – Divide two eight digit numbers accurately. F(x) = X2 + • Age 8: 10x F’(x) = 2x + – Mastered calculus. 10 • Age 15: – Studied advanced calculus and displayed such a depth of understanding that he was reported to have brought his tutor, the world renowned Mathematician Gábor Szegő, to tears. James Tam James Tam John von Neumann (1903 – 1957): 3 John von Neumann (1903 – 1957): 4 • By age 19 he was publishing his own papers (Mathematics). • “…there are many stories of how he was able to solve problems in a few minutes that others had worked on for months with no progress being • At age 30 he was made the youngest member of the newly evident”. (Williams) opened Institute for Advanced Study (IAS at Princeton). • During World War II he was a part of many scientific projects P1 P2 P3 – Atomic bomb research. P1 P4 P2 P5 • “He has to rank as one of this century’s most brilliant P3 P4 mathematicians and undoubtedly among the ranks of leading mathematicians of all time.” (Williams) AM 5 min P5 4 6 5 1 min Images What the???!!! 1) Man using computing device at desk: Seattle Municipal Archives, used under a James Tam Creative Commons license James Tam 2) Thinking man: http://ilovetobeselling.com/tips-for-attending-networking-events-near- 30 min and-far/ (Kathy Terrill) used under a Creative Commons license CPSC 409: Analog devices John von Neumann, The Person: Optional John von Neumann (1903 – 1957): 5 External Video • He also had the ability to write well about complex topics. • Interview questions directed to Dr. Von Neumann about topics – Because of this his name was associated with the architecture of the such as: the state of education of the time, the need for modern computer (von Neumann architecture) additional math/science/technical training: – He never claimed to invented the ideas by himself. – https://www.youtube.com/watch?v=vLbllFHBQM4 James Tam James Tam Von Neumann And The Moore School Von Neumann And The Moore School (2) • Early designs (ENIAC) • September 1944: – Machines of the day (Zuse Z series, Aiken Harvard series, Stibitz Bell – Von Neumann became a regular visitor at the Moore school (although too late series) used paper tape (read only storage). to participate in the ENIAC design). – Participated in the discussions in the design of a new machine (eventually called – Such designs rejected for the early ENIAC. EDVAC). • January 1944 (Moore school) • October 1944: – Mauchly and Eckert ironed out problems in the basic design. – Army Ordinance department gives $100,000 to the ENIAC budget to research – This gave them some time for reflection. developing the EDVAC. – Eckert: wrote a three page document about a magnetic calculating • Lt. Herman Goldstine (made an earlier request) machine. • John von Neumann (likely funding was provided at his request) – From this point onwards von Neumann actively participated in the design of the EDVAC. • Made many contributions • But the idea of a stored program computer (SPC) existed before his involvement James Tam James Tam Von Neumann And The Moore School (3) Von Neumann And The Moore School (4) • June 1945: “The First Draft of a Report on the EDVAC” • 1946: Eckert and Mauchly left the Moore school to found their – Described in great detail the concept of a stored program digital own company (Electronic Control Company…more on this computer. later). – Von Neumann was listed as the sole author. • Summer 1946: – Draft report meant as a progress report to be given the military – “Theory and Techniques for the Design of Electronic Digital Computers” sponsors. – Disseminated information about the design of the EDVAC to developers – But it was circulated within the Moore School and even to some on both sides of the Atlantic. outsiders. • The EDVAC was the first ‘conceived of’ stored program computer – Because it was the first document describing in detail the architecture • As we will see two other machines (UK) were completed before the EDVAC of a modern computer the term “von Neumann machine” coined. – (von Neumann: I didn’t invent it, I just wrote it down). – (Others at the Moore school: $%&#!!!). James Tam James Tam CPSC 409: Analog devices Computer Memory Types/Technologies Thermal Memories • Thermal memories • Andrew Donald Booth (1918 – 2009: United Kingdom) • Mechanical memories – Experimented with thermal memories • Delay line systems • Electrostatic storage mechanisms • Rotating magnetic memories • Static magnetic memories – The experiment was a failure (unreliable) James Tam James Tam Image: “A History of Computing Technology” (Williams) Mechanical Memories Mechanical Memories (2) • Used on a large scale by Zuse in the Z1 (“sliding plates”) • Relays (another example of mechanical memory) – Also used in several other machines (e.g., Z2+, Bell machines). • These forms of memory were much slower than the internal workings (e.g., arithmetic unit) of the electronic computer. • Andrew Donald Booth (again): disk-pin mechanical memory. James Tam James Tam “A History of Computing Technology” (Williams) Image: “A History of Computing Technology” (Williams) Mechanical Memories (3) Mechanical Memories (4) • Disk-pin mechanical memory Mechanical monsters access time ~0.25 second • Zuse’s Z3: – Additions: 0.25 – 0.3 seconds – Multiplication: two numbers every 4 – 5 seconds • Bell Model V (Twin machine) – Addition: 0.3 seconds – Multiplication: 0.8 seconds • Harvard Mark I – Additions: 0.3 seconds. – Multiplication: ~6 seconds. Electronic computer • ENIAC – Multiplication: in under 3 milliseconds (0.003 seconds) James Tam James Tam Image: “A History of Computing Technology” (Williams) CPSC 409: Analog devices Delay Line Systems Mercury Acoustic Delay Line • First type of memory to gain widespread acceptance • A binary number is represented using a series of pulses – Used in many machines: EDVAC, EDSAC, UNIVAC I, Pilot ACE, SEAC, LEO I – JT: think of it like a ‘binary Morse’ code etc. 5! • Types – Mercury acoustic <tap> <pause> <tap> – Air based delay lines – Slinky delay lines – Magnetostrictive delay lines – After a brief delay the pulses would be resent – Repeatedly pulsing the signal would allow for long term storage of the information James Tam James Tam Mercury Acoustic Delay Line (2) Mercury Acoustic Delay Line (3) • Developed by William Shockley (during WW II) • Technical issues: – (Bell labs: one of the developers of the electronic transistor).