Transcript Chapter 2 Slides

A+ Guide to Managing
and Maintaining Your PC
Fifth Edition
Chapter 2
How Hardware and Software
Work Together
Software


A set of instructions that controls hardware to
work
The “intelligence” of a computer
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
2
Operating Systems

Software that controls the fundamental
functions of a computer

Memory management

Data input/out

Applications execution

User interfaces

Networking

Data searching
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
3
OS as a Middleman
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
4
Popular Operating Systems






Windows 9x (95, 98, and me)
Windows NT, Windows 2000, and
Windows XP
Linux
DOS
Unix
Mac OS
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
5
File Systems


A crucial part of an operating system
Manage files on permanent storage devices
(e.g., hard disks)




Organize files hierarchically into directories
Access files through path
Operate files/directories: create, open, rename,
move, delete……
Read/write data from/to files
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
6
Windows File Systems

FAT (File Allocation Table)


Windows 95/98
NTFS

Windows NT/2000/XP
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
7
Experience the File System
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
8
Device Drivers

Software that controls devices

Obtain device drivers




Included in the operating system
Bundled with the device
Available on manufacturer’s web site
Device drivers vs. system BIOS
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
9
Practice: Device Drivers
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
10
System Resource

A tool used by hardware or software to
communication with each other




IRQ
Memory addresses
I/O addresses
DMA channel
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
11
Interrupt Request (IRQ)





A bus line that a hardware device uses to
signal the CPU that the device needs attention
Some lines have a higher priority than others
Each IRQ line is assigned a number (0 to 15
except 2) to identify it
IRQ 0 has the highest priority
IRQ0 – system clock
IRQ1 - keyboard
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
12
Practice: Viewing IRQ Assignments
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
13
Memory Addresses

Numbers assigned to physical memory (RAM
memory and ROM)

Software can use these addresses to access
memory

Memory addresses are communicated on the
address bus
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
14
I/O Addresses



Numbers assigned to hardware devices that
CPU can access a device
Each device “listens” for these numbers and
responds to the ones assigned to it
I/O addresses are communicated on the
address bus
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
15
I/O Addresses (continued)
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
16
Practice: Viewing I/O Addresses
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
17
Direct Memory Access (DMA)
Channels



A faster communication method than IRQ
Is used by hardware to transfer data directly
from/to memory, bypassing the CPU
Each DMA channel is assigned a number (0 to
7 except 4)
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
18
Practice: Examining DMA Channels
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
19
OS Tools to Examine a System

Device Manager



Windows 2000/XP and Windows 9x
Primary tool used to manage hardware devices
Third-party software
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
20
Summary




What’s operating system? What are the
commonly used operating systems?
What’s file system? What are the file systems
used in Windows?
What’s device driver, and how a hardware
device is managed by a device driver or system
BIOS?
What are system resources, and how do you
examine system resources?
A+ Guide to Managing and Maintaining Your PC, Fifth Edition
21