1. Computers Are Your Future © 2005 Prentice-Hall, Inc. CXC IT Unit 1 Objective 1 FUNDAMENTALS OF HARDWARE AND SOFTWARE The computer - basics

2. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 2 Don’t Be Intimidated by Hardware People feel threatened by computers because they fear computers are too complicated. Computers should be treated in the same way as any other electrical device.

3. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 3 What You Will Learn The four basic operations a computer performs The two main components of a computer system  Hardware  Software Explain how the CPU works. Explain the concepts of the Information Processing Cycle Understand how computers represent, transfer, and store data. Describe and explain the exterior and interior components of the system unit. Examples of hardware devices The information processing cycle

4. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 4 Understanding the Computer: Basic Definitions Computer – A machine that performs four basic operations: input, processing, output, and storage.

5. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 5 Understanding the Computer: Basic Definitions Computer system – A collection of related components that are designed to work together.  A system includes hardware and software. Hardware Software

6. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 6 Understanding the Computer: Basic Definitions Software – All the programs that give the computer its instructions.  Two categories of software: System software Application software

7. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 7 Input: Getting Data into the Computer Data – Unorganized raw materials made up of words, numbers, images, or sounds The first operation  Input devices enable the user to enter data into the computer. Input devices  The computer accepts data.

8. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 8 Keyboard Mouse – pointing device Microphone – speech - recognition Digital Cameras Input Devices

9. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 9 Processing: Transforming Data into Information The second operation  Computers transform data into information.  Processing circuitry: Processing circuitry  Central processing unit (CPU)  Random access memory (RAM) – plays an important role to hold instructions and data being used by the CPU DATA ININFORMATION OUT

10. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 10 Motherboard Central Processing Unit – CPU Random Access Memory– RAM Expansion Card Processing Devices

11. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 11 Output: Displaying Information The third operation  The computer shows the results of the processing operation in a way people can understand.  Output devices show the results of processing operations. Output devices

12. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 12 Monitor Printer Speakers Output Devices

13. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 13 Storage: Holding Programs and Data for Future Use The fourth operation  The computer saves the data or output so that it can be used again later.  Storage devices hold all programs and data that the computer uses. Storage devices

14. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 14 Hard Drive Floppy Disk Drive Zip Drive CD/DVD Drive Jaz Drive Tape Drive Micro Drive Storage Devices

15. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 15 Communications: Moving Data between Computers A fifth operation  Moving data within the computer or between computers  Communications devices – Enable computers to connect to a computer network. Communications devices  Network – Two or more computer systems that are connected.  Modem – A device that enables the computer to access other computers.

16. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 16 Modem Network Interface Card – NIC Communications Devices

17. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 17 The Information Processing Cycle In Action Input – You enter text in a word processing program.  You run the program’s spell checker program. Processing – The computer checks and compares all words entered with a list of correctly spelled words. Output – The computer provides a list of apparent misspellings.  You correct the spelling in your document. Storage – You save the revised document to a disk. Compoters A computer is a machine that perfirms four basic operations: input, processing, output, and storage. Together, these four operations are called the information proceesing cycle.

18. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 18 Advantages and Disadvantages of Using Computers AdvantagesDisadvantages SpeedInformation overload MemoryExpensive StorageSlower than RAM Reliability and accuracy Only applies to hardware, not software

19. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 19 Understanding the Computer: Basic Definitions Program – A list of instructions that tell the computer how to perform the four basic operations to accomplish a task.

20. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 20 Describing Hardware Performance üHardware performance refers to the amount of data a computer can store and how fast it can process the data. Mach Speed Socket 478 ATX Motherboard Intel Pentium 4 2.4Ghz Processor 80 GB 7200 RPM Hard Drive 512 MB DDR SDRAM Memory Module System Case

21. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 21 The System Unit üThe system unit is a boxlike case that houses the computer’s main hardware components (internal parts).

22. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 22 Desktop Notebook Personal Digital Assistant Types of System Units

23. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 23 Drive bays On/off switch Reset button Indicator lights FRONT BACK Outside the System Unit üThe front panel contains drive bays, various buttons, and indicator lights. üConnectors and ports are physical receptacles located on the back to connect peripheral devices to the computer.

24. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 24 Types of Connectors PS/2 port (mouse port) – Special serial port to connect mouse.PS/2 port (keyboard port) – Special serial port to connect keyboard.Universal Serial Bus (USB) – Allows up to 127 devices to be connected at a time. Serial port – Data flows in a series of pulses, one after another one bit at a time; slow data transfer rate. Parallel port – Data flows through eight wires allowing the transfer of eight bits of data simultaneously; faster than serial ports. VGA connector – A 15 pin connector used for monitorsGame port – A connector for high speed access for graphics-intensive interaction. Sound card connectors – Also called jacks, sound card connectors accept stereo mini-plugs. Microphone, line-in, line-out, and speaker connectors are plugged into the card. Point and click on a connector below to view information about it. Click again to remove the text.

25. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 25 Small computer system interface (SCSI) port – A parallel interface that enables up to eight devices to be connected to it. 1394 (FireWire) port – A high-speed connection for up to 63 devices. Infrared Data Association (IrDa) port – Infrared signals are used to communicate between peripheral devices and the system unit. Other Types of Connectors

26. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 26 Inside the System Unit üMotherboard (mainboard) – Large printed circuit board with thousands of electrical circuits üPower supply – Transforms alternating current (AC) from wall outlets to direct current (DC) needed by the computer üCooling fan – Keeps the system unit cool üInternal Speaker – Used for beeps when errors are encountered üDrive bays – Housing for the computer’s hard drive, floppy drive, and CD-ROM / DVD-ROM drives

27. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 27 The Motherboard The motherboard provides the centralized connection point for the computer’s components.  Most components are integrated circuits (chips).  Chips carry electrical current and contain electronic switches or transistors.

28. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 28 Components of the CPU üControl unit – Coordinates and controls all parts of the computer system.Control unit üArithmetic-logic unit – Performs arithmetic or logical operations.Arithmetic-logic unit üRegisters – Temporarily store the most frequently used instructions and data.

29. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 29 The Central Processing Unit: The Microprocessor CPU CPU socket Central processing unit (CPU) – A microprocessor that interprets and carries out instructions given by software. It controls the computer’s components.

30. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 30 The Chipset A chipset is a collection of chips that provide the switching circuitry needed to move data throughout the computer.

31. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 31 Parallel Processing üParallel processing involves using more than one CPU to improve performance. üComplex instruction set computer (CISC) – A chip that includes special-purpose circuits that carry out instructions at high speeds. üReduced instruction set computer (RISC) – A chip with a bare-bones instruction set that results in a faster processing speed than CISC chips.

32. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 32 KEYBOARD CPU RAM MONITOR CLICK ONCE TO BEGIN ANIMATION Processing a Word W E B W W EW E E B B B

33. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 33 Intel Advanced Micro Devices (AMD) Cyrix Motorola (Apple) Pentium IV Pentium MMX Pentium III Popular CPUs

34. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 34 The Control Unit üThe Control Unit manages four basic operations (fetch, decode, execute, and write-back). Information processing cycle – The term used to describe the four basic operations – Input, Processing, Storage and Output. Also called IPOS Cycle.  The four-step process is known as the Machine Cycle or Processing Cycle  The processing cycle consists of two phases:  Instruction Cycle –Fetch – Gets the next program instruction from the computer’s memory. –Decode – Figures out what the program is telling the computer to do.  Execution Cycle –Execute – Performs the requested action. –Write-back (Store) – Writes (stores) the results to a register or to memory.

35. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 35 The Arithmetic Logic Unit The Arithmetic Logic Unit (ALU) performs basic arithmetic and logic operations.  Adds, subtracts, multiplies, and divides  Compares alphanumeric data

36. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 36 Microprocessor Performance üData bus width – The number of pathways within the CPU that transfer data; they are measured in bits (8, 16, 32, or 64) üWord size – The maximum number of bits of data that the CPU can process at one time (8 bits, 16 bits, 32 bits, or 64 bits) üOperations per cycle (clock speed) – The number of clock cycles per second measured in megahertz (MHz) or gigahertz (GHz).  Superscalar operations – Carrying out more than one instruction per clock cycle.  Pipelining operations – Feeding a new instruction into the CPU at every step of the processing cycle.

37. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 37 Input/Output Bus The input/output bus provides a pathway so that the microprocessor can communicate with input/output devices. An input/output bus contains expansion slots which hold expansion cards.  PCI (Personal Computer Interface) slots are receptacles in which expansion cards are inserted. They support Plug and Play (PnP) devices. PCI slots Expansion Card

38. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 38 Summary – Fundamentals of Hardware and Software A computer is a machine that performs the operations of input, processing, output, and storage. A computer system is a collection of related components. Peripheral devices connect to the computer on the outside of the case. Computers have ports such as serial ports, parallel ports, SCSI ports, USB ports, FireWire ports, and IrDA ports to connect input/output devices. The motherboard is a circuit board that provides receptacles for chips and input/output buses. The central processing unit (CPU) contains the control unit (CU) and the arithmetic-logic unit (ALU). It manages the four basic operations (fetch, decode, execute, and write-back). The CPU’s performance is measured by the data bus width, operations per second, speed, and cache memory. The information processing cycle consists of the input, processing, output, and storage operations

39. Computers Are Your Future Chapter 4 © 2005 Prentice-Hall, IncSlide 39 The End