1. The System Unit The system unit is a case that contains electronic components of the computer used to process data 1 Page 210 Figure 4-1

2. The System Unit The inside of the system unit on a desktop personal computer includes: 2 Page 211 Figure 4-2

3. The System Unit The motherboard is the main circuit board of the system unit – A computer chip contains integrated circuits 3 Page 212 Figure 4-3

4. Processor The processor, also called the central processing unit (CPU), interprets and carries out the basic instructions that operate a computer – Contain a control unit and an arithmetic logic unit (ALU) 4 Page 213

5. 5 Figure 4-4

6. Processor The control unit is the component of the processor that directs and coordinates most of the operations in the computer The arithmetic logic unit (ALU) performs arithmetic, comparison, and other operations 6 Page 214

7. Processor For every instruction, a processor repeats a set of four basic operations, which comprise a machine cycle 7 Page 215 Figure 4-5

8. Processor Most current personal computers support pipelining – Processor begins fetching a second instruction before it completes the machine cycle for the first instruction 8 Pages 215 – 216 Figure 4-6

9. Processor 9 Page 216

10. Processor The leading manufacturers of personal computer processor chips are Intel and AMD 10 Pages 216 – 217 Figure 4-7

11. Processor Determine how you plan to use a new computer before selecting a processor 11 Page 218 Figure 4-8

12. Processor A processor chip generates heat that could cause the chip to burn up Require additional cooling – Heat sinks – Liquid cooling technology 12 Pages 219 - 220 Figures 4-9 – 4-10

13. Processor Parallel processing uses multiple processors simultaneously to execute a single program or task – Massively parallel processing involves hundreds or thousands of processors 13 Page 220 Figure 4-11

14. Data Representation 14 Page 221

15. Data Representation A computer circuit represents the 0 or the 1 electronically by the presence or absence of an electrical charge Eight bits grouped together as a unit are called a byte. A byte represents a single character in the computer 15 Page 221 Figures 4-12 – 4-13 ASCII character

16. Data Representation ASCII (American Standard Code for Information Interchange) is the most widely used coding scheme to represent data 16 Page 221 Figure 4-14

17. 17 Page 222 Figure 4-15

18. Memory Memory consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data Stores three basic categories of items: 18 Page 223

19. Memory Each location in memory has an address Memory size is measured in kilobytes (KB or K), megabytes (MB), gigabytes (GB), or terabytes (TB) 19 Page 223 Figure 4-17

20. Memory The system unit contains two types of memory: 20 Pages 223 - 224

21. Memory What is CMOS? p. 146 Next Uses battery power to retain information when other power is turned off Stores date, time, and computer’s startup information Complementary metal-oxide semiconductor memory Used in some RAM chips, flash memory chips, and other types of memory chips

22. 22 Page 224 Figure 4-18

23. Memory Three basic types of RAM chips exist: 23 Page 225 Figure 4-19

24. Memory RAM chips usually reside on a memory module and are inserted into memory slots 24 Page 225 Figure 4-20

25. Memory The amount of RAM necessary in a computer often depends on the types of software you plan to use 25 Page 226 Figure 4-21

26. Memory Memory cache speeds the processes of the computer because it stores frequently used instructions and data 26 Page 227 Figure 4-22

27. Memory 27 Page 228

28. Memory Access time is the amount of time it takes the processor to read from memory – Measured in nanoseconds 28 Page 229 Figures 4-24 – 4-25

29. Ports and Connectors 29 Page 232

30. The point at which a peripheral attaches to. Communicates with a system unit so that the peripheral can send data to or receive information from the computer. PORT

31. External devices often attaches by a cable to a port on the system unit. The term JACK is sometimes is used to identify audio and video ports. The front and back of system unit on desktop personal computer contain many ports. The ports of notebook computers including netbook and Tablet PCs are on the back, front and sides.

32. Joins a cable and a port. A connector at one end of the a cable attaches to a port on the system unit. A connector at the other end of the cable attaches to a port on the peripheral. CONNECTOR

33. Ports and Connectors What is a serial port? p. 149 Fig. 4-22 Next  Transmits one bit of data at a time  Connects slow-speed devices, such as a mouse, keyboard, or modem

34. Ports and Connectors What is a parallel port? p. 149 Fig. 4-23 Next  Connects devices that can transfer more than one bit at a time, such as a printer

35. Serial and parallel ports Extending The Processors Power Connect to printers or modems Parallel ports move bits simultaneously – Made of 8 – 32 wires – Internal busses are parallel Serial ports move one bit – Lower data flow than parallel – Requires control wires – UART converts from serial to parallel 35

36. Serial Communications Universal Asynchronous Receiver/Transmitter (UART) is a type of "asynchronous receiver/transmitter", a piece of computer hardware that translates data between parallel and serial forms. 36

37. Parallel Communications a parallel interface can handle a higher volume of data than a serial interface more than one bit can be transmitted through a parallel interface simultaneously 37

38. Ports and Connectors Other types of ports include: 38 Pages 234 - 236

39. Universal serial bus port Connect to up 127 different peripherals together with a single connector. USB 2.0 (Hi-Speed USB) more advanced and faster than USB. USB 3.0. USB 2.0 & USB 3.0 are backward compatible (they support older USB devices as well as USB 2.0 & USB 3.0) To attach multiple peripherals using a single USB port, can use USB Hub. USB Ports

40. A device that plugs in a USB port on the system unit. Contains multiple USB ports in which can plug cables from USB devices. Self-powered or bus-powered Self-powered USB hub draws power from an electrical outlets whereas bus-powered USB hub draws power from USB bus in the computer. Wireless USB hub is a receiver plugs into a USB port on the computer and it communicates wirelessly with the receiver. USB supports hot plugging and Plug and Play (attach peripherals while the computer is running) USB Hub

41. Universal Serial Bus (USB) an industry standard that defines the cables, connectors and communications protocols used in a bus for connection, communication and power supply between computers and electronic devices USB 1.0 and 1.1 – Specified data rates of 1.5 Mbit/s (Low-Bandwidth) and 12 Mbit/s (Full-Bandwidth). – Does not allow for extension cables or pass-through monitors (due to timing and power limitations) USB 2.0: – Added higher maximum bandwidth of 480 Mbit/s (60 MB/s) (now called "Hi-Speed") USB 3.0 – Maximum transmission speed of up to 5 Gbit/s (625 MB/s), which is more than 10 times as fast as USB 2.0 (480 Mbit/s, or 60 MB/s) 41

42. USB Universal Serial Bus Most popular external bus Supports up to 127 devices Hot swappable 42

43. USB A USB port can connect up to 127 different peripherals together with a single connector – You can attach multiple peripherals using a single USB port with a USB hub 43

44. System Devices USB port - intended to replace Serial, Parallel and PS/2 ports with a single standard. 127 devices can be connected to a single USB port. Hot swappable - devices can be connected and disconnected while the computer is on There are different USB standards in use: USB 1 - original standard - transfer data of 1.5MBps. USB 2 - current standard - transfer rate of 60MBps. USB3 - future standard (2009) transfer rate of 600MBps.

45. IEEE 1394 port Connect multiple types of devices that require faster data transmission speeds. The three latest version (FireWire 800, FireWire 1600 and FireWire 3200 ) have speeds faster than the original FireWire 400. Use FireWire hub to attach multiple devices to a single FireWire port. Supports Plug and Play. FireWire Ports

46. Firewire (IEEE 1394) FireWire, is a serial bus interface standard for high-speed communications and isochronous real-time data transfer. The 1394 interface is comparable with USB and often those two technologies are considered together, though USB has more market share IEEE 1394 replaced parallel SCSI in many applications, because of lower implementation costs and a simplified, more adaptable cabling system 46

47. Firewire (IEEE 1394) Cameras and video equipment Hot swappable Port is very expensive so is not very popular 47

48. System Devices FireWire port - (IEEE 1394) is an Apple technology There are two versions available and a third is planned: FW 400 - transfer rate of 50MBps. FW 800 - transfer rate of 100MBps. FW S3200 - transfer rate of 400MBps. USB devices must be connected to a host computer while FireWire devices can be connected to each other without using a computer.

49. Ports and Connectors A Bluetooth wireless port adapter converts a USB port into a Bluetooth port A smart phone might communicate with a notebook computer using an IrDA port 49 Page 235 Figures 4-33 – 4-34

50. Bluetooth technology uses radio waves to transmit data between two devices. Have to be within about 33 feet to each other. Contain a small chip that allows them to communicate with other Bluetooth-enabled computers or devices. Bluetooth headsets allow smart phone users to connect their telephone to a headset wirelessly. Bluetooth wireless port adapter that will convert an existing USB port into a Bluetooth port. Bluetooth PC cards and ExpressCard modules (traditional notebook computers and Tablets PCs). Bluetooth cards (smart phones and PDAs). Bluetooth Port

52. SCSI Small Computer System Interface Supports dozens of devices External devices daisy chain Fast hard drives and CD-ROMs 52

53. SCSI Instead of forcing the user to plug multiple cards into the computer’s expansion slots, a single SCSI adapter ex tends the bus outside the computer by way of a cable. SCSI is like an extension cord for the data bus. Up to 8 or 16 devices can be attached to a single bus

54. A special high-speed parallel port. Allows to attach SCSI peripherals (disk drivers and printers). SAS (serial-attached SCSI) transmits at mush faster speeds than parallel SCSI. For small computer system interference can daisy chain up to either 7 to 15 devices together. SCSI Port

55. External Series Advanced Technology Attachment. Allows to connect an external SATA hard disk to a computer. SATA hard disks are popular because of their fast data transmission speeds. Connections provide up to 6times faster data transmission speeds than external hard disks attached to a computer’s USB or FireWire port. eSATA Port

56. Infrared Data Association. Transmit data via infrared light waves. For these wireless device, to transmit signals to a computer, both the computer and the device must have an IrDA port. Align the IrDA port on the device with the IrDA port on the computer. Example : smart phone, PDA, keyboard, mouse and printer. Several of these devices use a high-speed IrDA port, sometimes called a fast infrared port. IrDA Port

57. Musical Instrument Digital Interface. The electronic music industry’s standard that defines how devices (sound cards and synthesizers) represent sound electronically. A special type of serial port that connects the system unit to a musical instrument. (electronic keyboard). A synthesizers can be a peripheral or a chip, creates sound from digital instructions. Has the capability of recording sounds that have been created by a synthesizer and then processing the sounds (the data) to create new sounds. MIDI Port

58. Buses What is a bus? p. 151 Fig. 4-24 Next  Channel that allows devices inside and attached to the computer to communicate with each other  System bus connects processor and main memory  Bus width determines number of bits transmitted at one time

59. Buses Expansion slots connect to expansion buses Common types of expansion buses include: 59 Page 238

60. Industry Standard Architecture bus standard for IBM PC compatible computers introduced with the IBM Personal Computer to support its Intel 8088 microprocessor's 8-bit external data bus and extended to 16 bits for the IBM Personal Computer/AT's Intel 80286 processor. further extended for use with 32-bit processors as Extended Industry Standard Architecture (EISA) the ISA bus was synchronous with the CPU clock, until sophisticated buffering methods were developed and implemented by chipsets to interface ISA to much faster CPUs 60

61. Industry standard Architecture (ISA)

62. Peripheral Control Interface (PCI) Connects modems and sound cards Found in most modern computers higher maximum system bus throughput

63. Peripheral Control Interface (PCI) 63

64. Accelerated Graphics Port (AGP) Connects video card to motherboard Extremely fast bus Found in all modern computers high-speed point-to-point channel for attaching a video card to a computer's motherboard, primarily to assist in the acceleration of 3D computer graphics. Since 2004 AGP has been progressively phased out in favor of PCI Express (PCIe). 64

65. Mobile Computers and Devices What is a mobile computer? p. 152 Fig. 4-26 Next  Notebook, weighing between 2.5 and 9 pounds, or mobile device such as a PDA

66. Mobile Computers and Devices What ports are on a notebook computer? p. 153 Fig. 4-27 Next

67. Mobile Computers and Devices What ports and slots are on a tablet PC? p. 153 Fig. 4-28 Next

68. Expansion Slots and Boards Allows users to configure the machine Slots allow the addition of new devices Devices are stored on cards Computer must be off before inserting 68

69. Expansion Slots and Adapter Cards An expansion slot is a socket on the motherboard that can hold an adapter card An adapter card enhances functions of a component of the system unit and/or provides connections to peripherals – Sound card and video card 69

70. Expansion Slots and Adapter Cards Removable flash memory includes: – Memory cards, USB flash drives, and PC Cards/Express Card modules 70