Computer Hardware and Software: Components, Peripherals, and Networks

Posted on Nov 12, 2024 in Technology

1. Computer Staff

The operation of all computers follows the same structure: information received through input peripherals is processed in a central unit, and the results are displayed using output peripherals. For a computer to process and store information, it must be encoded and broken down into numerical data. Computers handle data using bits (binary digits), which only support the numeric values 1 and 0. To handle this information, computers use electronic circuits that translate bits into small voltage and current changes. Electronic devices provide reliability, calculation accuracy, and high-speed processing.

All electronic equipment constitutes the hardware of the computer, while the programs that run on it constitute the software.

Motherboard

The motherboard has the following key elements:

  1. Microprocessor: Responsible for the main operation of the machine.
  2. Chipset: A set of circuits that manages data flow and the use of input and output devices, assisting the microprocessor.
  3. BIOS: Read-Only Memory (ROM) that contains information about basic input and output operations.
  4. Connectors: For different types of memory and expansion cards. Expansion cards can be chosen based on specific needs, such as graphics cards, sound cards, video capture cards, network cards, and modems.

2. System Processor

Microprocessor

The microprocessor is an integrated circuit that contains all the elements of the Central Processing Unit (CPU). It handles the following functions:

  • Executes instructions.
  • Performs arithmetic and logical operations.
  • Controls the machine centrally.
  • Exchanges data with the main memory.

Different Models of Microprocessors

Microprocessor-compatible computers primarily use Intel and AMD processors. Apple Macintosh computers use Motorola and PowerPC processors (developed by the AIM alliance of Apple, IBM, and Motorola).

Characteristics

  • Frequency: Number of clock cycles per second (measured in Hertz).
  • Data size: The amount of data it can operate on (measured in bits).
  • Number of transistors: Related to its technology and size.
  • Minimum element size: Measured in microns.
  • Power consumption: Measured in Watts.
  • Number of transactions per second: Measured in Mflops and Mips.
  • Maximum memory capacity: Measured in bytes.

Main Memory

Main memory stores the information the microprocessor needs to function. It has several main parts:

  • ROM-BIOS: Read-only memory.
  • RAM: Read and write memory (the majority of main memory).
  • CMOS-RAM: A small portion of read and write memory with low power consumption and volatility.

System Input and Output

This system is formed by ports and their connections to communication buses.

Ports of Communication

Connecting external peripherals to the motherboard is done through communication ports.

  • Specific Ports: Dedicated to connecting a specific peripheral.
  • Generic Ports: Most ports are generic and allow the connection of various peripherals, providing flexibility.

A useful port is the infrared (IR) port, which provides wireless communication with another computer or device within a limited range.

4. Expansion Cards

Expansion cards add functionality to the computer and allow the connection of various devices.

Graphics Card

The graphics card acts as an intermediary between the motherboard and the monitor. Its capabilities depend on the following characteristics:

  • Amount of RAM.
  • Size of each data point.
  • Processing speed.
  • Capacity to support 2D and 3D graphics.
  • Compatibility with video presentation systems.

Sound Card

Sound cards allow the recording and reproduction of sound on the PC. They typically provide the following connections:

  • Microphone input.
  • Speaker output.
  • Optical drive controller.
  • MIDI port (on some cards).

Other Expansion Cards

  • Network Card: Allows the computer to connect to a network.
  • Internal Modem: Acts as an intermediary for transmitting and receiving data over a telephone line.
  • TV and Radio Tuner: Receives television and radio signals.
  • Expansion Ports: Provide additional ports of various types.

5. Peripheral Devices

Basic Input Devices

The most common input devices are the keyboard and mouse.

  • Keyboard: Used to enter data, primarily alphanumeric characters.
  • Mouse: Streamlines work in a graphical environment.

Other Input Peripherals

Depending on the computer’s use, other input peripherals may be necessary:

  • Multimedia Game Peripherals: Add text, still images, animations, and sounds to games. Common examples include:
    • Microphones: For recording sounds.
    • Joysticks, gamepads, and steering wheels: For easier game control.
    • Digital camcorders: For capturing images in digital format.
  • Specific and Professional Peripherals: Designed for specialized uses. Examples include:
    • Barcode readers: Send digitized numbers to the computer.
    • Digitizer tablets and pens: Used in map drawing and graphic design.
    • Scanners: Capture images and printed text in digital format.

Output Peripherals

Output peripherals allow the retrieval of information in the form of images, sounds, and text.

  • Digital Monitor: Presents information to the user as images. The screen size is defined by the length of its diagonal. Pixels are the luminous points that make up the screen and affect image quality. Image adjustments like brightness and contrast are done through controls. Screen resolution depends on the number of pixels.
  • Printer: Transfers text documents and images to paper. Printer resolution is measured in dots per inch (DPI). Print speed is measured in pages per minute (PPM) or characters per second (CPS).

Bidirectional Peripherals

Bidirectional peripherals allow both input and output of data.

  • Modem: Allows the computer to connect to a telephone line. There are internal and external modems, with the main difference being their transmission speed.
  • Touchscreen: Images are presented on a screen that is sensitive to touch, allowing interaction with the displayed information using fingers.
  • Multifunction Printers: Integrate the functionalities of a scanner and printer into a single device, allowing them to be used as a copier and fax machine.

6. Mass Storage Devices

Mass storage devices are used to save large amounts of information economically and reliably.

Magnetic Storage

  • Floppy Disks and Hard Disks: Disks are plastic with a magnetized layer, protected by a plastic housing with a sliding window for access to the disk.
  • Removable Tape: Plastic tapes with a magnetizable layer.
  • Hard Drives: Formed by metal plates on which a read/write head slides.

Magnetic Operation of Units

  • To write a bit, an electrical impulse is sent to the writing head’s coil (called a magnetic dipole).
  • To read a bit, the reading head slides over the surface of one of the dipoles, inducing an electric current or impulse that is interpreted as a “1” or “0” according to its polarity.

Optical Storage

  • CD-ROM: A read-only disc capable of storing up to 700 MB of data or 80 minutes of digitized audio.
  • CD-R: Has the same characteristics as a CD-ROM but can only be written to once.
  • DVD: A read-only disc that stores several gigabytes of data.

Optical Performance of Units

The speed of a burning, reading, or rewriting unit is expressed as a multiple of 150 kilobits/second.

  • To write a bit, a powerful laser is used to create a mark on the surface of an aluminum layer, leaving a notch that is interpreted as a “1” when written.
  • To read a bit, a low-power laser is used, and the reflected or absorbed light is interpreted as a “0” or “1”.

Electronic Storage Units

Flash memory stores information with or without a charge for an indefinite period. This type of memory uses semiconductor materials in the form of integrated circuits.

  • To write a bit, a small electrical current is injected into a terminal of a MOSFET transistor.
  • To read a bit, the charge status of the MOSFET transistor is checked.

7. Computer Networks

Network Size and Reach

Based on their dimensions, there are three types of networks:

  1. LAN (Local Area Network): Generally for private use. Common topologies include:
    • Linear bus and tree: Computers are connected one after another in a transmission line.
    • Ring: The transmission line is closed, forming a loop.
    • Star: The most commonly used topology. All devices are connected to a central node that manages communication between them.
  2. MAN (Metropolitan Area Network): Cover a small geographical area, such as a city.
  3. WAN (Wide Area Network): Extensive networks that connect cities, countries, or continents.

Elements of a Local Network

Any local network consists of software (programs for network management) and hardware (physical components).

Network Switches and Hubs

In a star topology, a central device manages connections between devices.

  • Hub: Connects devices through its ports. When data arrives at one port, it is relayed to all other ports.
  • Switch: An improved hub. It only relays data to the necessary ports, allowing different data rates for each branch.

8. Network Transmission Media

Different media can be used to connect devices in a local network:

  • Twisted-pair cable: Formed by eight colored wires protected by a plastic sleeve.
  • Coaxial cable: Can use the RG-58 type, formed by a central conductor, plastic insulation, a metal mesh, and an external shield.
  • Fiber optic: Uses pulses of light to transmit data. It consists of a glass or plastic core surrounded by materials that prevent signal loss and protect the fiber from breakage.