computer evolution n performance

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

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
• Princeton Institute for Advanced Studies
— IAS
• Completed 1952

IAS – details
• 1000 x 40 bit words
— Binary number
— 2 x 20 bit instructions
• Set of registers (storage in CPU)
— Memory Buffer Register
— Memory Address Register
— Instruction Register
— Instruction Buffer Register
— Program Counter
— Accumulator
— Multiplier Quotient

Commercial Computers
• 1947 - 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
• 1953 - the 701
— IBM’s first stored program computer
— Scientific calculations
• 1955 - the 702
— Business applications
• Lead to 700/7000 series

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 - 1957
— 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

Generations of Computer
• Vacuum tube - 1946-1957
• Transistor - 1958-1964
• Small scale integration - 1965 on
— Up to 100 devices on a chip
• Medium scale integration - to 1971
— 100-3,000 devices on a chip
• Large scale integration - 1971-1977
— 3,000 - 100,000 devices on a chip
• Very large scale integration - 1978 to date
— 100,000 - 100,000,000 devices on a chip
• Ultra large scale integration
— Over 100,000,000 devices on a chip