Supplementary Topics

1
Supplementary Topics

• Computer Architecture
• Computer Organization
• Organization and Architecture
• History of Computers
• Generations of Computers
• Moores Law

2
Computer Architecture (1)

• Definition?
• The design of integrated system which provides a
  useful tool to the programmer. (Baer)
• The study of the structure, behaviour, and
  design of computers. (Hayes)
• The design of the system specification at a
  general or subsystem level. (Abd-Alla)
• The art of designing a machine that will be a
  pleasure to work with. (Foster)

3
Computer Architecture (2)

• The interface between the hardware and the
  lowest level software. (Hennessy and Patterson)
• Keyword
• Design
• System
• Structure
• Art Tool Interface

4
Computer Architecture (3)

• Therefore, computer architecture refers to
• Attributes of a system visible to programmers
• Attributes that have a direct impact on the
  execution of programs
• Attributes
• Instruction set
• Data representation
• I/O mechanisms
• Addressing techniques

5
Computer Organization

• Organization refers to operational units and
  their interconnections that realize the
  architectural specifications.
• Attributes hardware details transparent to
  programmers
• Control signals
• Computer/peripheral interface
• Memory technology

6
Architecture Organization (1)

• Architecture is attributes visible to programmers
• Organization is how features are implemented
• Example
• Architecture multiply instruction?
• Organization hardware multiply unit or done by
  repeated addition? (how is it implemented?)
• Example
• IBM/370 architecture
• different models (organizations)

7
Architecture Organization (2)

• Family Concept
• All Intel x86 family share the same basic
  architecture
• The IBM System/370 family share the same basic
  architecture
• This gives code compatibility (at least
  backwards)
• Organization differs between different versions

8
History of Computers (1)

• Pre-mechanical Era
• Abacus (ancient China)
• Mechanical Era (1623 1940s)
• Wilhelm Schickhard (1623)
• Automatically , -, x, ?
• Blaise Pascal (1642)
• Mass produced first working machine (50)
• Only , -
• Gottfried Liebniz (1673)
• Improved on Pascals machine (, -, x, ?)

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History of Computers (2)

• Mechanical Era (contd)
• Charles Babbage (1822)
• Father of modern computer
• Automatic computation of math tables
• Any math operation
• Punch cards
• Modern structure I/O, storage, ALU
• 1 sec. x 1 min.
• George Boole (1847)
• Mathmatical analysis of logic

10
History of Computers (3)

• Mechanical Era (contd)
• Herman Hollerith (1889)
• Modern day punch card machine
• Tabulating machine company ? predecessor of
• Konard Zuse (1938)
• First working mechanical computer, Z1 (later on
  Z2 Z4)
• First programmable computer
• Binary floating point machine
• Howard Aiken (1943)
• Harvard Mark I, built by IBM
• Implementation of Babbages machine

IBM
11
History of Computers (4)

• Summary of Mechanical Era
• Contributions
• Reduce calculation time
• Increase accuracy
• Drawback
• Speed limited by moving parts
• Cumbersome
• Expensive
• Unreliable
• Entered the Electronic Era (1945 present)!!

12
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 Basis for virtually every machine
  designed since then

13
Structure of von Neumann machine
14
Generations of Computer

• First generation Vacuum tube - 1946-1957
• Second generation Transistor - 1958-1964
• Third generation Integrated circuits 1965
  1971
• Small scale integration - 1965 on
• Up to 100 devices on a chip
• Medium scale integration - to 1971
• 100-3,000 devices on a chip
• Semiconductor memory (1970)
• Microprocessor (1971)

15
Generations of Computer

• Fourth generation Large scale integration (LSI)
  - 1971-1977
• 3,000 - 100,000 devices on a chip
• Intel 8080 first general-purpose microprocessor
  (1974)
• Fifth generation 1978 present
• Very large scale integration (VLSI) - 1978 to
  date
• 100,000 - 100,000,000 devices on a chip
• Ultra large scale integration (ULSI)
• Over 100,000,000 devices on a chip
• GSI ??

16
Moores Law

• Increased density of components on chip
• Number of transistors on a chip will double every
  year
• Since 1970s development has slowed a little
• Number of transistors doubles every 18 months
• Cost of a chip has remained almost unchanged
• Higher packing density means shorter electrical
  paths, giving higher performance
• Smaller size gives
• increased flexibility
• Reduced power and
• cooling requirements
• Fewer interconnections
• increases reliability