IN1006: Systems Architecture History Quiz

Systems Architecture - IN1006

• Course Instructor: Dr. H. Asad
• Course Title: Introduction to Computer systems Architecture-History
• Course Code: IN1006

Learning Objectives

• History of Computers
• (Computer) Systems Architecture
• von Neumann components of a computer system
• Basic hardware components of a computer
• Semiconductors
• Introduction to Moore's law and technology trends
• Concept of Abstraction
• Computer system in terms of layers of functionality

Early Devices

• Mechanical calculating machines (1642 - 1945)
• Mechanical Calculating Clock: Add, subtract 6-digit numbers (W. Schickard - 1635)
• Difference Engine and Analytical Engine by Charles Babbage (1791-1871)
  • Analytical Engine had many modern computer components like ALU, memory, and input/output devices.

History of Computers

First Generation (1945 - 1953): Vacuum Tube Computers

• ENIAC (1946): First all-electronic, general-purpose computer
• Used 17,468 vacuum tubes
• Occupied 1800 square feet, weighed 30 tons, and consumed 174 kW of power
• Had 1,000 bits of memory

Second Generation (1955 - 1965): Transistors

• Used transistors, invented in 1948
• Computers became smaller, faster, and consumed less power.
• Still bulky and expensive.
• Examples: IBM 7094, DEC PDP-1, CDC 6600

Third Generation (1965 - 1980): Integrated Circuits

• Integrated circuits (or microchips)
• Each integrated circuit contains dozens of transistors.
• Computers became faster, smaller, and cheaper
• Examples: IBM 360, DEC PDP-11, Cray 1

Fourth Generation (1980 - Now): VLSI

• Very Large Scale Integration (VLSI): 10,000+ components per chip
• Introduced personal computers (PCs): IBM PC, Apple Mac
• Modern computers: System on a Chip (SoC)
  • Integrate all components onto one chip.
• Examples: Laptops, tablets, smartphones, smart watches

Computer History Driver: Technology of Computer Processors & Memory

• Computers improved through breakthroughs in underlying technology
• Mechanical → Vacuum tube → Transistor → Integrated Circuit → Very Large Scale Integration → System on Chip

Semiconductors

• Material type: Conductors allow electricity to flow. Insulators prevent electricity flow.
• Semiconductors can switch between these states
• Built transistors that function as switches
• Silicon is a semiconductor used to manufacture computer logic efficiently and inexpensively
• Popularized as "Silicon Chips"

Moore's Law

• Transistor count on integrated circuits doubles approximately every 18-24 months
• Gordon Moore (1965)
• Shrinking transistors have improved computing capabilities for over 60 years.
• Potential areas for future improvements: cloud computing, high performance computing, quantum computing.

Computer Systems Architecture

• Fundamental organization of a computer system: Components, relationships, and principles
• Enables understanding of capabilities.
• Realization of capabilities by components
• Ability to extend/modify computer systems
• Effect on capabilities after modifications

The von Neumann Model: An Abstract Model

• Basis for all modern stored-program computers

• Consists of five components:

  • Control Unit
  • Arithmetic Logic Unit (ALU)
  • Registers
  • Main Memory
  • Input/Output (I/O) System

• Sequential instruction processing using a single datapath between CPU and main memory: The von Neumann bottleneck

The von Neumann Model (cont'd)

• Fetch-decode-execute cycle: Control unit fetches the next instruction, decodes it, fetches data operands as needed, ALU performs instructions, results are stored.
• Returning to step (1) to execute the next instruction

The Fetch-Execute Cycle: What's Your Computer Actually Doing?

• CPU components: Program Counter, Instruction Register, Accumulator, Clock

The von Neumann Model Has Evolved

• Incremental improvements: Specialized buses, floating-point units, cache memories, separate processors
• Separate data and instruction buses (Harvard architecture), cache memory improves performance

Computer Hardware Components: Personal Computer

• Main System: CPU, RAM, disks and other storage
• Input Devices: Keyboard, mouse, scanners, camera, etc.
• Output Devices: Monitor, speakers, printers, etc.

Key Processor Components

• Registers: Local storage for key data
• Memory Management Unit (MMU): Interfacing with main memory
• Instruction Fetcher/Decoder: Fetches and decodes instructions from the program counter
• Arithmetic Logic Unit (ALU): Performs calculations/operations
• Datapath/Control: Controls information flow, enabling instruction execution

Inside a Modern CPU

• Discusses computer hardware inside a CPU and displays computer components

Abstraction

• Act of representing essential features without background details
• Reduction of complexity
• Efficient design and implementation of complex software systems

Key Layers of Abstraction in Computer Systems

• Systems can be decomposed into layers of abstraction
• Abstraction layers hide lower-level details from higher-level interactions
• Avoid unnecessary detail, focusing on higher-level functionality.

In Summary

• Brief overview of computer history
• Abstract model of computers and technology trends
• Computer system architecture and key hardware components
• Importance of abstraction in computer systems