Introduction to Computer & Its Architecture

Definition of a Computer

• A computer is a general-purpose, programmable device that processes information through input and output.
• It performs mathematical and non-mathematical operations based on instructions to achieve desired results.

Characteristics of Computers

• Speed: Computers process data at an incredibly fast rate, measured in MHz (MegaHertz), equivalent to one million instructions per second.
• Accuracy: They operate with high accuracy, determined by the design and instructions. Human errors can lead to incorrect data input, emphasized by the GIGO principle (Garbage In, Garbage Out).
• Reliability: Computers perform operations without failure and require no human intervention for processing tasks.
• Diligence: They do not experience tiredness or lack of concentration, maintaining consistent performance.
• Versatility: Capable of handling multiple tasks simultaneously, such as calculations and graphics processing.
• Storage Capability: Unlike humans, computers can store large volumes of data, typically using storage devices like magnetic tapes or disks.
• No IQ: Computers do not possess intelligence or emotions; they operate based solely on programmed instructions.

Generational Evolution of Computers

• Third Generation (1964-1970): Characterized by smaller and more reliable devices, integrating keyboards and monitors for user interaction.
• Fourth Generation (Early 1970s - Present): Features integrated circuits and microprocessors, enabling portable computers and rapid growth in data communication. Types include digital watches, pocket calculators, and personal computers.

Types of Computers According to Size & Processing Power

• Microcomputers: Small, low-cost computers with a microprocessor as the CPU, often personal computers. Subcategories include:
  • Desktop: Commonly used with separate components.
  • Workstation: Enhanced desktop for specific tasks like 3D graphics.
  • Laptop: Portable computers integrating multiple components into one unit.
  • Handheld: Compact devices with touch input, including smartphones and PDAs.
  • Embedded Computers: Microprocessors programmed for specific tasks.

Interaction Between Functional Blocks

• Processor (CPU): Interprets and executes instructions, consisting of:
  • Control Unit: Directs and coordinates operations.
  • Arithmetic Logic Unit (ALU): Performs arithmetic and logical operations.
• System Bus: A set of wires allowing communication between CPU, memory, and I/O devices. Comprised of:
  • Data Bus: Transfers data between components.
  • Address Bus: Carries memory address information from CPU to memory.
  • Control Bus: Coordinates data transfer and device readiness.

Registers in CPU

• Temporary high-speed storage areas that hold data and instructions currently processed by the CPU. Key registers include:
  • Program Counter (PC): Tracks the next instruction to be executed.
  • Instruction Register (IR): Holds instructions for decoding by the control unit.
  • Memory Address Register (MAR): Contains the address of the next memory location.
  • Memory Buffer Register (MBR): Stores data being sent to or from the CPU.
  • Accumulator (ACC): Temporary storage for results produced by ALU.
  • Data Register (DR): Holds operands and other necessary data.

This quiz covers the fundamental concepts of computers and their architecture. It includes definitions of a computer, its characteristics, and the basic functioning of input and output processes. Test your knowledge on what defines a computer and its capabilities.