Supporting I/O Devices

1. Supporting I/O Devices

2. Peripheral Installations • Both hardware and software must be installed • Device driver must be written specifically for the OS • More than one peripheral device might attempt to use same resources • Update drivers, the firmware, or both

3. Installation Overview • Install the device (internal or external) • Install the device driver • Install the application software

4. Ports

5. Using Ports and Expansion Slots for Add-on Device • Ports • Serial • Parallel • USB • IEEE 1394 • SCSI • Expansion slots

6. Port Speeds

7. Using Serial Ports • Transmit data in single bits (serially) • Nine or 25 pins • Almost always male • Originally intended for input and output devices • Configured as COM1, COM2, COM3, or COM4

8. Using Serial Ports (continued) • Port assignments are made in CMOS setup • Conform to standard interface called RS-232c • Data Terminal Equipment (DTE) and Data Communications Equipment (DCE) designations

9. Port Comparison

10. Default Port Assignments

11. Serial Port Specifications

12. Null Modem Connection • Enables data transmission between two DTE devices without the need for modems • Special cable (null modem cable) has several wires cross-connected to simulate modem connection

13. Pin Connections for a 25-Pin Null Modem Cable

14. Wire Connections on a 25-Pin Null Modem Cable

15. Using Parallel Ports • Transmit data in parallel, eight bits at a time • Almost always female • Originally intended for printers • Can be configured as LPT1, LPT2, or LPT3 • Port assignments are made in CMOS setup • Avoid using a cable longer than 15 feet to ensure data integrity

16. Types of Parallel Ports • Standard parallel port (SPP) • Allows data to flow in only one direction • Slowest of the three types • Enhanced Parallel Port (EPP) • Bi-directional • Extended Capabilities Port (ECP) • Bi-directional • Uses the DMA channel

17. A Standard Parallel Port

18. Using USB Ports • Effortless installation of slow peripheral devices • Much faster than regular serial ports; use higher-quality cabling • Easier to manage; eliminate need to manually resolve resource conflicts • Likely to replace serial and parallel ports

19. Using USB Ports (continued) • Allow for hot-swapping; are hot-pluggable • Most current motherboards have one to four USB ports • Managed by a USB host controller • As many as 127 USB devices can be daisy-chained together using USB devices

20. USB Ports

21. USB Host Controller

22. USB Device Installation • Motherboard or expansion card that provides a USB port • OS that supports USB • USB device • USB device driver

23. Installing a USB Device • Some devices (eg, printers) must be plugged in before installation • Some devices (eg, scanners) require the driver to be installed first • Using Device Manager, verify that the USB controller is installed and working properly

24. Using IEEE 1394 Ports • Transmit data serially; faster than USB • Likely to replace SCSI for high-volume, multimedia external devices • Provide either a 4-pin or 6-pin connector • Hot-pluggable • Up to 63 devices can be daisy-chained together and managed by a host controller using one set of system resources • Use isochronous data transfer

25. IEEE 1394 Port Standards • IEEE 1394A • Supports data speeds up to 1.2 Gbps • Allows for cable lengths up to 15 feet • IEEE 1394B • Supports speeds up to 3.2 Gbps • Allows for cable length up to 328 feet

26. IEEE 1394 Cable Connections

27. Using IEEE 1394 Ports

28. Using PCI Expansion Slots • PCI bus • Currently the standard I/O bus • PCI bus controller • Manages the PCI bus and expansion slots • Assigns IRQ and I/O addresses to PCI expansion cards • Use Device Manager to see which IRQ has been assigned to a PCI device

29. Using ISA Expansion Slots • Configuration is not automated • ISA bus does not manage system resources, as do USB and PCI bus controllers • ISA device must request system resources at startup

30. Solving Problems with Legacy ISA Expansion Cards • Resource conflicts between two legacy devices • Use Windows Device Manager • Problems using legacy device drivers • Try to locate a 32-bit driver for the device

31. Solving Problems with Legacy ISA Expansion Cards (continued) • Create empty copy of Autoexec.bat and Config.sys on hard drive then • boot up into MS-DOS mode • run setup program from command prompt • copy appropriate command lines into original versions of Autoexec.bat and Config.sys

32. Solving Problems with Legacy ISA Cards

33. Solving Problems with Legacy ISA Cards (continued)

34. Keyboards • Traditional straight design or ergonomic design • Two technologies for keys making contact • Foil contact • Metal contact • Installing keyboards

35. Keyboard Connectors • PS/2 connector (or mini-DIN) • Small, round, with six pins • DIN connector • Round with five pins • USB port • Wireless connection • Requires a driver

36. Keyboard Connectors (continued)

37. Pinouts for Keyboard Connectors

38. A Keyboard Adapter

39. Pointing Devices

40. How a Wheel Mouse Works

41. How a Mouse Connectsto the Computer • Dedicated round mouse port (motherboard mouse or PS/2-compatible mouse) • Mouse bus card (bus mouse) • Serial port (serial mouse) • USB port • Y-connection with the keyboard • Cordless technology

42. Pointing Devices • Touch screens • Other pointing devices • Trackballs • Touch pads

43. Computer Video • Necessary components for video output • Monitors • Video cards

44. Monitors • Rated by screen size, resolution, refresh rate, and interlace features • Most meet standards for Super VGA • Use CRT (cathode-ray tube) or LCD (liquid crystal display) technology

45. How a CRT Monitor Works

46. Choosing the Right Monitor

47. Flat Panel Monitors

48. Video Cards • Methods of data transfer • RGB video port • DVI port • Composite video • S-Video

49. Methods of Data Transfer

50. Transferring Data with anS-Video Cable