A Brief Introduction to the History of Computing - 2 ANU Faculty of Engineering and IT Department of Computer Science COMP1200 Perspectives on Computing Chris Johnson April 2003

Intro to history of computing: hardware2 Intro to history of computing – 4.2  The early years of electronic computing  Moore’s Law  The 3 or 4 Generations of computing technology - hardware

Intro to history of computing: hardware3 1. early years: Big Ideas: the von Neumann architecture The stored program computer

Intro to history of computing: hardware4 1. early years: Big Ideas - the stored program computer Why is the ability to store the program in memory significant?

Intro to history of computing: hardware5 1. early years: Generations of electronic computing 1.electronic valves(1943)1948 (vacuum tubes) 2.individual solid-state transistors integrated solid-state circuits1964 LSI, MSI, VLSI 4. VLSI & the Personal Computer1981

Intro to history of computing: hardware6 1. early years: small ideas... “I think there is a world market for maybe five computers” IBM’s chairman Thomas J Watson, 1943 (133 Million PCs were sold in 2000)

Intro to history of computing: hardware7 1. early years: the 1 st generation example: Bendix G built 2,160 x 29 bit words (about 8KBytes storage) speed: 2 kHz max 180 tube packages (valves) 300 germanium diode packages (transistor precursor)

Intro to history of computing: hardware8 1. early years: 1 st generation – valves (vacuum tubes) Burroughs B205, ca This module represents one decimal digit in the ALU accumulator University of Virginia museum

Intro to history of computing: hardware9 1. early years: 1 st generation hardware  based on vacuum tubes: like small light bulbs, 2, contacts common (diode, triode,..., pentode)  slow: computer logic needs internal switching of tube states: limited to kHz speeds  expensive, so computers had only small ALU  unreliable: vacuum tubes fail frequently, randomly - like light bulbs  runs hot, required a lot of power & cooling  physically big  showed that electronic computing was useful

Intro to history of computing: hardware10 1. early years: 1 st generation software  programs writen as numeric codes (machine language) and in primitive assembly languages (a few words and code names: A1, M100)  system software tiny: small subroutine libraries for numeric routine (e.g.SIN, TAN) and I/O formatting (e.g. convert internal number to decimal digits)  manual operation: load next program from paper tape by physical switches at console: no “operating system”

Intro to history of computing: hardware11 1. early years: 2 nd generation  from approximately 1959  transistor a general purpose electronic amplification device: cooler, faster, smaller, much more reliable than valves  computer systems software: came with manufacturer-supplied Operating System for batch operation, still needed an operator to load paper and magnetic tapes and paper cards – no online backing store files

Intro to history of computing: hardware st and 2 nd generation I/O: input/output TYPICAL INPUT/OUTPUT USED A SINGLE TYPEWRITER-LIKE DEVICE WITH MECHANICAL KEYBOARD, FAN-FOLD PAPER. PAPER TAPE, MAYBE PUNCH CARD READER AND PUNCH. ONE PERSON AT A TIME. EARLY INTERFACE DEVICES WERE THE SAME AS COMMUNICATIONS TELETYPES, RUNNING AT SPEED OF CHARACTERS PER SECOND. NO GRAPHICS AT ALL ONE FONT - OFTEN ONLY UPPERCASE CHARACTERS.

Intro to history of computing: hardware nd generation - transistors  software: by end of generation (early 1960s) each manufacturer sold compilers for machine independent, application-oriented programming languages for their machines: FORTRAN, COBOL, Algol, LISP  no easy portability of programs, magnetic tapes for fast secondary storage  no general computer networks

Intro to history of computing: hardware rd generation electronics  ability to manufacture Integrated Circuit containing many transistors on single “chip” of silicon: 1964  fewer physical components, less soldering, cheaper, more reliable manufacturing - fit more logic on each circuit board  computers now used custom-designed integrated circuits (ICs)  allowed circuits to work faster: MHz not kHz 4 microsecond ADD (0.25 MIPS) [IBM 360/50: 1965] 0.75 microsec ADD (1.25 MIPS) [IBM 360/75: 1968]  computers more reliable, physically smaller, larger memory 360/50: 256KByte (1965) 360/75: 1 MByte (1968)

Intro to history of computing: hardware rd generation computers IBM Conducting a war by computer Vietnam, circa 1968Philip Jones Griffiths

Intro to history of computing: hardware rd generation: von Neumann architecture plus virtual memory Secondary storage use for online file storage I/O controllers Virtual memory Online file storage

Intro to history of computing: hardware rd generation storage and software  add fast online secondary storage – disks - use for scratch files, database, general user files and Virtual Memory [Atlas - UK 1961]  Operating Systems - yes! High level Languages – yes yes yes!

Intro to history of computing: hardware18 1. Big Ideas - the stored program computer Why is the ability to store the program in memory significant? (2): the 3 rd generation.

Intro to history of computing: hardware19 2. Moore’s Law The density of transistors on a chip (i.e. the number per unit area) doubles every 18 months  1964: Gordon Moore (Intel) observed the fact and fitted the “law” to the figures to that date  literally “exponential growth”  is it still true 40 years later?  what does doubling every 1.5 or 2 years actually imply?

Intro to history of computing: hardware20 2. Moore’s Law Number of transistors on one chip - Intel 80x86 family processors , , , , ,000,000 data from Intel

Intro to history of computing: hardware21 2. Moore’s Law data from Intel

Intro to history of computing: hardware rd & 4 th generation: von Neumann architecture with virtual memory and cache Secondary storage use for online file storage I/O controllers Virtual memory Online file storage fast cache memory

Intro to history of computing: hardware23 3. From 3 rd to 4 th generation  3 rd generation dates from approx 1964 mainframe computers first, then minis  minicomputers: e.g.DEC PDP/8, PDP/11, Birth of UNIX operating system1975  microcomputers PET TRS  Apple II, VisiCalc spreadsheet1979  IBM PC, Microsoft DOS1981

Intro to history of computing: hardware th generation (my numbering)  no hardware change marks the start  IBM PC personal computers 1981  personal productivity tools: spreadsheets, word processing programs (and Powerpoint)  GUI – WIMP interface Windows–Icons–Menus-Pointer invented 1975 Xerox PARC hit market 1984 (Mac) 1985 (IBM PC)