COMP 268 Computer Organization and Assembly Language A Brief History of Computing Architecture

Figure 1-2. A six-level computer.

Steps needed to run Fortran program (circa 1960) 1.Retrieve the FORTRAN compiler card deck from the cabinet, place it in the card reader, and push the start button. 2.Place the card deck containing the FORTRAN source file program in the card reader and push the continue button. 3.When the computer pauses, feed the FORTRAN source file into the card reader for the 2 nd pass. 4.If there are no errors, the compiler will punch the “compiled” program on a new card deck. If the compiler does detect 1 or more errors, you will have to make the necessary corrections to your FORTRAN program and return to step 1. 5.Once you have a “compiled” program that is free of syntax errors, feed it into the card reader along with the data card deck and the subroutine library deck that is available in the cabinet. 6.If the program works successfully, the output will be printed on paper. If there is a run-time error, a core dump will be printed instead. If you receive a core dump, you will need to take it home and find the error in your program. Once the errors have been corrected begin again with step 1.

Sample FORTRAN job for early operating systems

0 th Generation – Mechanical Computers (1642 – 1945) Charles Babbage & Ada Lovelace - Difference Engine and Analytical Engine Konrad Zuse – Electronic relays in 1930’s John Atanasoff – ABC computer at Iowa State College Howard Aiken – Mark I at Harvard (1944) 1 st Generation – Vacuum Tubes (1945 – 1955) Alan Turing – COLOSSUS in Great Britain (1943) John Mauchley & J. Presper Eckert – ENIAC at MIT (1945) Unisys John von Neumann – “stored program concept” & the EDSAC 2 nd Generation – Transistors (1955 – 1965) Kenneth Olsen - PDP-1 & PDP-8 IBM’s 7094 Seymour Cray and CDC’s rd Generation – Integrated Circuits (1965 – 1980) IBM’s System/360 DEC’s PDP-11 4 th Generation – VLSI ( ??) Computer Generations Alan Turing

ENIAC - background Electronic Numerical Integrator And Computer Eckert and Mauchly University of Pennsylvania Trajectory tables for weapons Started 1943 Finished 1946 –Too late for war effort Used until 1955

ENIAC - details Decimal (not binary) 20 accumulators of 10 digits Programmed manually by switches 18,000 vacuum tubes 30 tons 15,000 square feet 140 kW power consumption 5,000 additions per second John Mauchly J. Presper Eckert

von Neumann/Turing Stored Program concept Main memory storing programs and data ALU operating on binary data Control unit interpreting instructions from memory and executing Input and output equipment operated by control unit John von Neumann

Commercial Computers Eckert-Mauchly Computer Corporation UNIVAC I (Universal Automatic Computer) US Bureau of Census 1950 calculations Became part of Sperry-Rand Corporation Late 1950s - UNIVAC II –Faster –More memory

IBM Punched-card processing equipment the IBM 701 –IBM’s first stored program computer –Scientific calculations the IBM 702 –Business applications Thomas Watson, Sr & IBM 701 Keypunch Machine

Transistors Replaced vacuum tubes Smaller Cheaper Less heat dissipation Solid State device Made from Silicon (Sand) Invented 1947 at Bell Labs William Shockley et al.

Transistor Based Computers Second generation machines NCR & RCA produced small transistor machines IBM 7000 DEC –Produced PDP-1

Microelectronics Literally - “small electronics” A computer is made up of gates, memory cells and interconnections These can be manufactured on a semiconductor e.g. silicon wafer

Moore’s law: Transistor density doubles every 18 months

Moore’s Law Transistor density doubles every 18 months 10 G 1 G 100 M 10 M 1 M 100 K 10 K 1 K 0.1 K