1 / 11

Logical Computer System

Logical Computer System. Unit 2, Introduction to Computer Systems. Logical vs. Physical. A computer system can be represented in either a logical or physical form Both are useful in understanding Computer Systems theory. Physical Computer System.

iain
Download Presentation

Logical Computer System

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Logical Computer System Unit 2, Introduction to Computer Systems

  2. Logical vs. Physical • A computer system can be represented in either a logical or physical form • Both are useful in understanding Computer Systems theory. Logical Computer System Presentation Unit 2

  3. Physical Computer System • The actual hardware as seen in real life • Contains micro-electronics and physical mechanisms • Powered by electricity • Very detailed and complex • Difficult to fully understand without a working knowledge of electronics. Logical Computer System Presentation Unit 2

  4. Logical Computer System • A basic model of a computer system • The model is built from a number of different blocks • Each block performs a different task • All blocks work together to process data into information • Model is conceptual – could not be physically the same in real-life • Less complex, easier to understand. Logical Computer System Presentation Unit 2

  5. Logical Computer System CPU Control Unit ALU Input Device Main Memory Output Device Backing Storage Test me! Logical Computer System Presentation Unit 2

  6. Input Device • A device which lets the user “feed” data into the computer • Converts data into a stream of electronic digital signals • Digital signals will be converted into binary inside the computer • Some sample real-world input devices; keyboard, mouse, light pen, scanner, microphone, camera, motion sensors, biometric devices such as a fingerprint scanner, OMR/OCR readers for direct data capture etc. Logical Computer System Presentation Unit 2

  7. Main Memory • Stores data before being processed by CPU • Stores program being executed by computer • Is volatile - when power is removed, data is lost • Often called “RAM” - Random Access Memory • Stores processed data before it is output • Contents are filled by Input Devices, Backing Storage or the CPU • Data that needs to be saved (for future use) is written to the backing storage. Logical Computer System Presentation Unit 2

  8. Backing Storage • Usually non-volatile, although its contents may be deleted • Loads previously stored data into the main memory • Loads previously written programs into memory for processing by CPU • In the real world may be internal or external • Usually mechanical (eg Hard Drive, CD or DVD Writer) which slows a computer system • Data is usually “read” (loaded) or “written” (saved). Logical Computer System Presentation Unit 2

  9. Output Devices • Converts processed data, stored in main memory, into a form that can be understood by a human as information • Some sample real-world output devices; monitor (CRT or TFT/LCD), speakers, printer, plotter, robot, etc. Logical Computer System Presentation Unit 2

  10. CPU • CPU is an abbreviation of Central Processing Unit • The CPU is often called the Processor • The CPU is the computer’s brain • The speed of the CPU generally determines the efficiency and power of the computer system • The CPU consists of two sub-systems: The ALU (Arithmetic/Logic Unit) and the Control Unit. The former performs basic calculations and logical comparisons. The latter co-ordinates and runs the computer’s operations. Logical Computer System Presentation Unit 2

  11. Activity Complete the worksheet activity by identifying the correct components on the logical computer system model. Logical Computer System Presentation Unit 2

More Related