A+ Guide to Software Managing, Maintaining and Troubleshooting THIRD EDITION Chapter 2 How an OS Works with Hardware and Other Software

2A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions You Will Learn… About the hardware components of a PC How an OS relates to hardware and software About the system resources that hardware and software use for communication

3A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Introducing Hardware Ports Used by External Devices The CPU Memory or RAM Buses on the Motherboard BIOS on the Motherboard and Other Circuit Boards CMOS Setup Chip Hard Drives and Other Secondary Storage Devices

4A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Internal Devices

5A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Ports Used by External Devices

6A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions The Motherboard Largest and most complex circuit board All devices connect to the CPU by way of the motherboard Provides ports for external devices and slots for expansion cards

7A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions The Motherboard (continued)

8A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Motherboard Components Central processing unit (CPU) Random access memory (RAM) Traces or wires Expansion slots

9A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Motherboard Components (continued) Connectors for drives (e.g., hard drive, floppy drive, CD-ROM drive) ROM BIOS memory chip  Permanently stores instructions that control basic hardware functions CMOS configuration chip Power supply connections

10A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions The CPU Controls all hardware components in the computer Installed in a slot or socket in the motherboard Operate in one of two modes  Real mode (16 bits)  Protected mode (32 bits) Has lines coming to it that are embedded on motherboard collectively called a bus

11A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions The CPU (continued)

12A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Memory or RAM Temporarily holds data and instructions Stored on memory modules  SIMMs  DIMMs (most common)  RIMMs Memory addresses  Numbers assigned to each usable cell of memory

13A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions System Properties

14A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Buses on the Motherboard 8-bit and 16-bit ISA (Industry Standard Architecture) buses System bus (memory bus, front-side bus, local bus) PCI (Peripheral Component Interconnect) bus AGP (Accelerated Graphics Port) bus used for a single video card

15A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Buses on the Motherboard (continued) USB bus that provides USB ports for slower I/O buses IEEE 1394 (FireWire) used for faster I/O devices

16A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions AGP slot and PCI slots

17A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions BIOS on the Motherboard and Other Circuit Boards Motherboard contains vital ROM chip that contains basic input/output system (BIOS)  Startup BIOS (used to start the computer)  System BIOS (used by the OS to manage simple devices)

18A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Advanced Configuration and Power Interface (ACPI) Power-saving feature Allows system to be powered up by external device such as a keyboard Supported by Windows 9x and 2000/XP Supported by most recent motherboard BIOS

19A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Plug and Play Makes hardware device installations easier Plug and Play BIOS begins process of configuring hardware devices Plug and Play OS uses information from the BIOS to complete hardware configuration Windows 9x and Windows 2000/XP support Plug and Play  Windows NT does not

20A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Plug and Play BIOS

21A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions CMOS Setup Chip Contains very small amount of memory adequate to hold computer configuration information Responsible for remembering  Current date and time  Which hard and floppy drives are present  How serial and parallel ports are configured, etc.

22A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions CMOS Setup Chip (continued) Retains its data even when computer is turned off Program to change CMOS is stored in ROM BIOS

23A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Primary Storage and Secondary Storage Secondary storage devices  Store data and instructions permanently  To be processed, data and instructions must be copied from secondary storage to memory  Common devices: hard drives, floppy disk drives, CD-ROM drives, DVD drives, and Zip drives Primary storage (memory)  Holds data and instructions temporarily

24A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions A Hard Drive Subsystem

25A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Hard Drives and Other Secondary Storage Devices Integrated Drive Electronics (IDE) standards govern how hard drives work Enhanced Integrated Drive Electronics (EIDE) standards govern how secondary devices interface with a system

26A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Hard Drives and Other Secondary Storage Devices (continued) Most motherboards have EIDE connections for two cables (primary and secondary) Each cable can connect two devices for a total of four devices in one system

27A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions How an Operating System Works An OS Manages Files and Folders An OS Manages Applications An OS Manages Hardware BIOS and Device Drivers Use System Resources

28A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions An OS Manages Files and Folders OS uses a file system to organize files and folders on secondary storage Windows uses:  FAT or FAT16 (File Allocation Table)  FAT32 (Most recent version of FAT16)  NTFS (New Technology File System)

29A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Tracks, Sectors, and Clusters Tracks are concentric circles on the surface of a disk A Sectors is a segment of a track A Cluster:  is made up of one or more sectors  is the smallest unit of space on a disk for data storage

30A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Tracks, Sectors, and Clusters (continued)

31A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Files and Directories Every OS manages a hard drive by using directories, subdirectories, and files A directory table is a list of files and subdirectories The root directory is created when a hard drive is first installed and formatted For drive C, the root directory is written as C:\

32A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Hard Drive File Organization

33A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Partitions and Logical Drives on a Hard Drive A hard drive is divided into one or more partitions Primary partition, usually C: Only one extended partition permitted

34A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Extended Partition Can have one or more logical drives (or volumes) Each logical drive formatted with its own file system Each logical drive has its own root directory and subdirectories

35A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Organization of a Hard Drive

36A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions An OS Manages Applications The OS installs and runs application software An application depends on an OS to:  Provide access to hardware resources  Manage its data in memory  Manage its data in secondary storage  Perform other background tasks

37A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Loading Application Software Using the Windows Desktop

38A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Loading Application Software Using the Windows Desktop (continued) Use a shortcut Use the Start menu Use the Run command Use Windows Explorer or My Computer

39A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Loading Application Software Using the Windows Desktop (continued)

40A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Real (16-Bit) and Protected (32-Bit) Operating Modes Real Mode  Applications have complete access to hardware

41A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Real (16-Bit) and Protected (32-Bit) Operating Modes (continued) Protected Mode  OS controls how application can access hardware  More than one program can run at a time and each is “protected” from other programs accessing hardware  Enables preemptive multitasking, in which the OS allots CPU time to application for specified time period and then preempts the processing

42A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions 16-Bit and 32-Bit Software 16-bit Windows software  Written for Windows 3.x  Accesses data 16 bits at a time  Each program written so that it should not infringe on resources of other applications running 32-bit software  Written for Windows 95 and later

43A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions An OS Manages Hardware Device drivers or BIOS Operating system Application software

44A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions An OS Manages Hardware (continued)

45A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions How an OS Uses Device Drivers Device drivers are designed to interface with specific hardware devices Usually written for a particular OS and need to be rewritten for use with another OS provides some device drivers  Device manufacturer provides others

46A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions How an OS Uses Device Drivers (continued) Windows 95 and Windows 98  16-bit real mode device drivers  32-bit protected mode device drivers Windows Me, Windows NT/2000/XP  Only 32-bit protected mode device drivers

47A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions How an OS Uses Device Drivers (continued)

48A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Drivers Under Windows 2000/XP Always check hardware compatibility list (HCL) Check manufacturer’s Web site for updated device drivers It’s best to use the latest driver available

49A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Drivers Under Windows 2000/XP (continued)

50A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Drivers Under Windows 9x OS comes with 32-bit device drivers for hundreds of hardware devices Some older hardware may need to use 16-bit real mode device drivers  Loaded by entries in Config.sys, Autoexec.bat, and System.ini

51A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions How an OS Uses System BIOS to Manage Devices OS uses the system BIOS to communicate with simple devices  Floppy drive  Keyboard  Hard drive OS can use either system BIOS or a device driver for the hard drive  Device driver is faster

52A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions BIOS Setup

53A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions BIOS Setup (continued)

54A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions BIOS and Device Drivers Use System Resources Interrupt request (IRQ) numbers I/O Addresses Memory addresses Direct memory address (DMA) channels

55A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions BIOS and Device Drivers Use System Resources (continued)

56A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions OS Tools to Examine a System Device Manager System Information Microsoft Diagnostic (MSD)

57A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Manager Does not exist in Windows NT Windows XP: Start, right-click My Computer, Properties Windows 2000: Right-click My Computer, Properties, Hardware tab, Device Manager Windows 9x: Right-click My Computer, Properties, Device Manager

58A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Manager (continued)

59A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Manager (continued) For more information about a device, right-click the device and check it Properties Can be used to:  Update a device driver  Enable or disable a device  Change system resources assigned to a device  Uninstall a device

60A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Device Manager (continued)

61A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions System Information Similar to Device Manager plus more information, e.g.,  BIOS version  Directory where the OS is installed  How system resources are used  Information about device drivers and status To run System Information, click Start, Run, enter MSinfo32.exe, OK

62A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions System Information (continued)

63A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Microsoft Diagnostic (MSD) Available only in DOS and Windows 9x Provides information about the system  Memory  Video  Ports  Device drivers Click Start, Run, enter MSD.exe, Click OK

64A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Microsoft Diagnostic (MSD) ( continued)

65A+ Guide to Software: Managing, Maintaining and Troubleshooting, Third Editions Summary The hardware components of a PC How an OS relates to hardware and software The system resources that hardware and software use for communication