Introduction to components of computer system

This presentation is about the Introduction of components of computer system.

1. Introduction to Components of Computer System Subject: Programming for Problem Solving Subject code: KCS-201

2. Computers are everywhere At work e-mail messages Memos letters manage calendars calculate payroll track inventory generate invoices. At school teachers use computers to assist with classroom instruction. research genealogy At Home play games to communicate purchase goods online listen to music or radio broadcasts watch or create videos and movies read books and magazines share stories ,

3. Definiton The word “computer “ comes from the word “compute”, which means to calculate. A computer is an electronic device, operating under the control of instructions stored in its own memory. It can accept data (input), process the data according to specified rules (process), produce results (output), and store the results (storage) for future use. Generally , the term is used to describe a collection of electric, electronic, and mechanical components known as hardware .

4. Very fast speed of calculation Store large amount of information for future purpose in short time Great ability to enhance the communication system Accuracy of calculation is very high Characteristics of a Computer

5. Computer and communication system Manufacturing, construction engineering and project management Military, space applications Logistic, distribution and supply chain management Business process, healthcare management, research in different sector Areas of Application

6. Computer Classification Personal Computer : A small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data . Workstation: A powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor.

7. Mini-computer: A multi-user computer capable of supporting from 10 to hundreds of users simultaneously . Mainframe Computer: A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously . Super Computer: An extremely fast computer that can perform hundreds of millions of instructions per second.

8. Anatomy of Computer

9. Input devices are the part of hardware to provide human understanding information to a computing system in digital form. Input is any data or instructions entered into the memory of a computer Any hardware component allows user to enter data and instructions in to a computer. Input Device

10. Keyboard Used to enter information into the computer and for giving commands. A standard computer keyboard is called a QWERTY keyboard

11. Ball Mouse An input device operated by rolling its ball across a flat surface. The mouse is used to control the onscreen pointer by pointing and clicking, doubleclicking , or dragging objects on the screen.

12. Optical Mouse It is an advanced computer pointing device. It uses Light-Emitting Diode(LED) in place of the traditional mouse ball. Movement is detected by sensing changes in reflected light.

13. Examples of input devices Keyboard : Alphanumeric Keyboard, MIDI keyboard Pointing Devices : Mouse, touchpad, trackball Speech Recognization : Microphone( using voice speech recognition or biometric verification) Biometric system : Fingerprint scanner Smart Card Reader : ATM, employee, business card, Punch card reader Digital camera and digital camcorder . Medical instruments : ECG, EEG, X-ray, CT scan, and ultrasound images Finger (with touch screen or Windows Touch ). Gamepad , joystick Light gun, Light pen, Magnetic ink (like the ink found on checks), Pen or stylus

14. Central Processing Unit (CPU) This is the central part of computer which is responsible to produce output for a particular input or sometime automatic system production. A CPU is brain of a computer. It is responsible for all functions and processes. Regarding computing power, the CPU is the most important element of a computer system.

15. CPU comprises of : Control Unit (CU) Arithmetic Logic Unit(ALU) Memory

16. Control Unit controls and co-ordinates computer components. Read the code for the next instruction to be executed. Increment the program counter so it points to the next instruction. Read whatever data the instruction requires from cells in memory. Provide the necessary data to an ALU or register. If the instruction requires an ALU or specialized hardware to complete, instruct the hardware to perform the requested operation.

17. Arithmetic & Logic Unit (ALU) It executes arithmetic operation as addition, subtraction , multiplication, division. It performs logical operations as comparison, combinational logic (AND, OR, NOT, XOR, XNOR). Registers :Stores the data that is to be executed next, "very fast storage area".

18. Memory Executable data are stored in primary memory. Access of primary memory is very fast and volatile in nature (except ROM ). Data is stored temporally while program is running – Main Memory . To store data for long-term, to preserve programs and data while not in use – Backing Storage . Primary and secondary memory

19. Primary Memory Temporary area for holding data. To store the program currently being executed To hold data produced while the programme is running. Primary Memory are of two types 1 . RAM 2 . ROM

20. RAM(Random Access Memory) Major portion of the Primary Memory Memory that is used by the program in execution If the computer gets turned off, RAM will lose all the data. Static RAM & Dynamic RAM

21. STATIC RAM The memory retains as long as power remains applied . Uses Flip Flop circuitory . Is more faster. DYNAMIC RAM Need continues Refreshing in order to maintain the data. It uses transistors and capacitors in circuits Slow and consumes more power

22. ROM (Read Only Memory) Memory which we can only read but cannot write on. Non-volatile . Used to store some firmware programs. PROM – Programmable Read Only Memory EPROM – Erasable and Programmable read Only Memory. EEPROM – Electrically Erasable and Programmable read Only Memory

23. Secondary Memory Permanent memory of the system. More storage capacity. It is the Backing Store . Magnetic Disk & Optical Disk

24. Magnetic Disc Stored data in the form of Magnetic directions. Hard Disk & Floppy Disk

25. Hard Disk Access to data is far faster than access to data in floppy disks. Read/Write Head is positioned close to the disk. Disk is attached to a spindle. Spindle is rotated by a motor. Speed of disk depends on the speed of motor.

26. Floppy Disk Consists of a plastic disk coated with iron oxide. Disk access mechanism is arranged as a hardware unit called disk drive. Drive contains motor, Read/Write Head etc. Head comes in contact with the disk through the data access area. Disk is rotated to pass the sectors through the head

27. Optical disk It is an electronic storage medium. Read operation is done using low powered laser beam. A laser read the dots and then the data is converted to an electrical signal . The output form of this devise is in audio and visual format CD-ROM – Compact Disk-Read Only Memory. CD – R – Compact Disk – Recordable. CD-RW – Compact Disk – Rewritable DVD – ROM – Digital Versatile Disk – Read Only Memory DVD – RAM - Digital Versatile Disk – Random Access Memory