CSCI-235 Micro-Computers in Science

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CSCI-235Micro-Computers in Science

• Course Information Introduction

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• Class webpage
• http//www.stfx.ca/people/igondra/csci235
• What is a computer?
• A good start at defining what a computer is might
  be It is a device that processes data and
  produces information
• Is this a good definition?
• It is far too broad in its applicability. With
  this definition, many things can be classified as
  a computer (e.g., a thermostat, a VCR)

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• What is this definition missing?
• Have you ever written a term paper on your VCR or
  calculated your tax return with your thermostat?
• Those devices were manufactured with the ability
  to perform a single, limited task
• A computer can be programmed!
• There is a particular kind of data that a
  computer requires in addition to any other data
  it might receive a program
• Better definition It is a programmable device
  that processes data and produces information
• Is the human brain a computer?

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• Gross Anatomy
• Hardware equipment associated with the computer
• Input devices, processor, output devices, storage
• Software instructions that tell the hardware
  what to do
• Two categories of software
• System software
• Application software

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• von Neumann Architecture
• Although specific components may vary, virtually
  all modern computers have the same underlying
  structure
• known as the von Neumann architecture
• Named after computer pioneer, John von Neumann,
  who popularized the design in the early 1950's

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• The von Neumann architecture identifies 3
  essential components
• Input/Output Devices (I/O) allow the user to
  interact with the computer
• Memory stores information to be processed as well
  as programs (instructions specifying the steps
  necessary to complete specific tasks)
• Central Processing Unit (CPU) carries out the
  instructions to process information

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• First computer?
• The first actual calculating mechanism known to
  us is the abacus, which was invented about 2000
  years ago

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• Many references cite the French mathematician,
  physicist, and theologian Blaise Pascal as being
  the inventor of the first mechanical calculator
  in 1642, the Arithmetic Machine

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• However, it now appears that the first mechanical
  calculator may have been conceived by someone
  else almost 150 years earlier than Pascal's
  machine. Can you guess who?
• Leonardo Da Vinci

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• In the early 1800s, a French silk weaver called
  Joseph-Marie Jacquard invented a way of
  automatically controlling the warp and weft
  threads on a silk loom by recording patterns of
  holes in a string of cards

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• The first device that might be considered to be a
  computer in the modern sense of the word was the
  Difference Engine to automatically calculate
  mathematical tables conceived in 1822 by the
  British mathematician and inventor Charles
  Babbage
• The Difference Engine was only partially
  completed when Babbage conceived the idea of
  another, more sophisticated machine called the
  Analytical Engine
• The Analytical Engine was intended to use loops
  of Jacquard's punched cards to control an
  automatic calculator, which could make decisions
  based on the results of previous computations

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• Working with Babbage was Augusta Ada Lovelace,
  the daughter of the English poet Lord Byron. Ada,
  who was a splendid mathematician and one of the
  few people who fully understood Babbage's vision,
  created a program for the Analytical Engine
• Ada is now credited as being the first computer
  programmer and, in 1979, a modern programming
  language was named ADA in her honor

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• In 1939, a German engineer, Konrad Zuse built the
  first programmable, general-purpose digital
  computer. His computer was built from electric
  relays to automate engineering calculations
• I was too lazy to calculate and so I invented
• the computer.
• John Atanasoff invented the Atanasoff-Berry
  Computer (ABC) the first electronic digital
  computer. Built in 1939, this computer used
  vacuum tubes and was based on binary arithmetic.
  It was never a fully operational product

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• In 1944, Howard Aiken completed the Mark I, the
  largest electromechanical calculator ever built.
  It was built with electromechanical relays and
  followed instructions punched in paper tape

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• The first computer bug

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• In 1945, Mauchly and Eckert built the ENIAC
  (Electronic Numerical Integrator and Computer).
  The ENIAC was built with 18,000 vacuum tubes that
  failed on an average of once every seven minutes
• After the war, they created the UNIVAC I - the
  first general-purpose commercial computer

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• First-Generation Computers
• 1930s 1940s
• Vacuum tubes used as switches
• Large computers
• Extremely slow by todays standards
• Prone to frequent failure
• Includes the ABC, Mark I, ENIAC, UNIVAC,and
  others of similar design

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• Second-Generation Computers
• 1950s mid-1960s
• Transistors used as switches
• Smaller than vacuum-tube-built computers
• As much as a thousand times faster than
  first-generation computers
• More reliable and less expensive

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• Third-Generation Computers
• Late 1960s
• Hundreds of transistors packed into a single
  integrated circuit on a silicon chip
• Dramatic reduction in size and cost
• Significant increases in reliability, speed, and
  efficiency
• Mass production techniques to manufacture chips
  inexpensively

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• Fourth-Generation Computers
• 1970s to present
• Complete computer on a chip
• Radical change in the appearance, capability and
  availability of computers