Basic Computer Engineering
Chapter – 1
Lecture – 1
Lecture – 2
Lecture – 3
Lecture – 4
Lecture – 5
Lecture – 6
Generation of Computers
Development of technologies used to fabricate the processors, memories and I/O units of the computers has been divided into various generations as given below: First generation Second generation Third generation Fourth generation Beyond the fourth generation
First generation: 1946 to 1955: Computers of this generation used Vacuum Tubes. The computes were built using stored program concept. Ex: ENIAC, EDSAC, IBM 701. Computers of this age typically used about ten thousand vacuum tubes. They were bulky in size had slow operating speed, short life time and limited programming facilities.
Second generation: 1955 to 1965: Computers of this generation used the germanium transistors as the active switching electronic device. Ex: IBM 7000, B5000, IBM 1401. Comparatively smaller in size About ten times faster operating speed as compared to first generation vacuum tube based computers. Consumed less power, had fairly good reliability. Availability of large memory was an added advantage.
Third generation: 1965 to 1975: The computers of this generation used the Integrated Circuits as the active electronic components. Ex: IBM system 360, PDP minicomputer etc. They were still smaller in size. They had powerful CPUs with the capacity of executing 1 million instructions per second (MIPS). Used to consume very less power consumption.
Fourth generation: 1976 to 1990: The computers of this generation used the LSI chips like microprocessor as their active electronic element. HCL horizen III, and WIPRO’S Uniplus+ HCL’s Busybee PC etc. They used high speed microprocessor as CPU. They were more user friendly and highly reliable systems. They had large storage capacity disk memories. Beyond Fourth Generation: 1990 onwards: Specialized and dedicated VLSI chips are used to control specific functions of these computers. Modern Desktop PC’s, Laptops or Notebook Computers.
Computer Organization refers to the way in which a computer’s hardware components, including the central processing unit (CPU), memory, storage devices, and input/output (I/O) devices, are structured and interconnected to perform tasks efficiently. It encompasses the design and arrangement of hardware elements, as well as their interaction, to ensure the computer’s functionality and the execution of software programs.
Key aspects of computer organization include:
Hardware Components: Understanding the individual components of a computer, such as the CPU, memory, storage devices, and peripheral devices, and how they work together.
Instruction Set Architecture (ISA): Defining the set of instructions that a CPU can execute and how these instructions are encoded and processed.
Memory Hierarchy: Designing the system’s memory structure, including cache memory, RAM, and secondary storage, to optimize data access and storage.
Input/Output Organization: Managing the connections and protocols for input and output devices to enable data transfer between the computer and external devices.
Data Representation: Determining how data is represented in binary form and how different data types are stored and manipulated by the hardware.
Parallel Processing: Exploring the ways in which multiple processors or cores can work together to increase computing power and efficiency.
Pipelining and Superscalar Processing: Implementing techniques that enable the CPU to execute multiple instructions simultaneously to improve performance.
Computer organization is a fundamental concept in computer science and is essential for computer engineers, architects, and programmers to understand how computers function at the hardware level, allowing them to design efficient and high-performance systems.
Computer memory, often called “memory” in the context of computing, is a critical component of a computer’s hardware for storing data and instructions that the computer’s processor (CPU) needs to perform various tasks. Computer memory plays a fundamental role in the operation of a computer system, enabling it to store and retrieve data quickly and efficiently temporarily. There are several types of memory in a computer, including:
Random Access Memory (RAM): RAM is the primary form of computer memory used to store data and instructions that the CPU is actively using or processing. It is a volatile memory, meaning its contents are lost when the computer is powered off. RAM provides fast and temporary storage for running applications, the operating system, and data in active use.
Read-Only Memory (ROM): ROM is non-volatile memory that contains firmware or software instructions that are permanently stored and cannot be easily modified by the user. It is responsible for booting up the computer and initializing the hardware.
Cache Memory: Cache memory is a small but extremely high-speed form between the CPU and RAM. It stores frequently accessed data and instructions to speed up CPU retrieval, improving overall system performance.
Virtual Memory: Virtual memory is a memory management technique that uses a portion of a computer’s secondary storage (usually a hard drive or SSD) to simulate additional RAM. It allows the computer to run programs requiring more memory than the physical RAM.
Flash Memory: Flash memory is a non-volatile memory commonly used in solid-state drives (SSDs), USB drives, memory cards, and mobile devices. It is non-volatile and is used for long-term storage, meaning it retains data even when the power is turned off.
Hard Disk Drive (HDD):
While not traditional memory, HDDs store data magnetically on spinning disks and are a form of non-volatile secondary storage. They are used for long-term data storage and are slower but offer larger storage capacities.
Solid-State Drive (SSD):
SSDs are a type of non-volatile memory used for long-term storage, similar to HDDs, but use flash memory instead of spinning disks. They offer faster data access and are commonly used to improve overall system performance.
Registers are small, high-speed storage areas within the CPU used for temporary storage of data and instructions. They are crucial for executing instructions efficiently.
This includes various non-volatile storage devices like optical drives (e.g., DVDs), tape drives, and magnetic tape, which are used for long-term data archiving.
Computer memory is vital for the execution of software programs, the storage and retrieval of data, and the overall performance of a computer system. The speed, capacity, and type of memory a computer uses can significantly impact its efficiency and capabilities. As technology advances, memory capacities and speeds improve, allowing computers to handle more complex tasks and run applications faster.
Computer Input Output Devices
Computer input and output devices are hardware components that enable communication between a computer and the external world. These devices facilitate inputting data and commands into the computer (input devices) and presenting processed data to the user (output devices). Here are common examples of both input and output devices:
- Keyboard: A standard input device that allows users to enter text, numbers, and commands into the computer.
- Mouse: A pointing device for navigating the graphical user interface, selecting items, and interacting with on-screen elements.
- Touchscreen: A display that allows users to input data or control the computer by touching the screen directly. Common in smartphones, tablets, and some computers.
- Scanner: Converted physical documents, images, or objects into digital format (e.g., scanned text or photos).
- Digital Camera: Captures photographs or videos and transfers them to the computer for editing or storage.
- Microphone: An audio input device that records sound and voice for applications like voice recognition or video conferencing.
- Joystick and Game Controllers: These are used for gaming and simulations, allowing users to control on-screen characters or vehicles.
- Barcode Reader: Reads barcodes on products for inventory management and sales processing.
- Biometric Devices include fingerprint scanners and facial recognition systems for user authentication and security.
- Light Pen: An input device for drawing or selecting objects on a computer screen by pointing directly at the display.
- Monitor/Display: The most common output device used to visually present text, images, and videos on a screen.
- Printer: Produces hard copies of digital documents, including text and images. Common types include inkjet, laser, and dot matrix printers.
- Speakers: Audio output devices that produce sound for multimedia applications, games, and audio playback.
- Projector: Used to display computer screen content on a larger screen or wall, commonly in presentations and classrooms.
- Headphones: Output audio devices for personal listening to audio or video content.
- Plotters: Specialized output devices for producing high-quality drawings, diagrams, and charts.
- Braille Display: Converts digital text into Braille for visually impaired users.
- Haptic Feedback Devices: Provide tactile feedback, such as vibrations or force feedback, for enhanced user experiences in gaming and simulations.
- LED/LCD Panels: Used for digital signage, information displays, and advertising.
- E-readers: Devices designed specifically for reading digital books and documents, often with E-ink displays.
These input and output devices are essential for the interaction between humans and computers. They enable users to provide input to the computer, receive output in various forms, and engage with various applications and tasks.