Computer Maintenance Technology Tutorial

Author: Gong Bing
Publisher:
Publish Date: 2002-01-01
Features: This book introduces the basic knowledge and techniques of computer system maintenance and hardware repair. The book is divided into 3 chapters. Chapter 1 explains the maintenance of the Windows 9x operating system and the handling of operating system faults. Chapter 2 covers the system data structure, organization, and directory structure of disks, as well as the maintenance of files and data files. It provides detailed discussions on the maintenance and repair methods of the Master Boot Record (MBR) sector, partition table, extended partition table, system boot (BOOT) area, FAT table, and root directory, along with programming demonstrations. Chapter 3 is a guide for comprehensive experiments. This book is a required textbook for students of major vocational colleges and technical schools, and can also serve as a self-study manual for individuals with secondary or higher education.
Chapter 1: Windows 9x System Maintenance
1.1 Computer System
1.1.1 Composition of a Computer System
When you turn on the power to start a computer, you may see a series of startup screens on the screen, but have you ever wondered what the computer is actually doing while displaying these screens? This is the basic knowledge for understanding and maintaining a computer system. Below, we will introduce what the computer does from the moment the power is turned on to the appearance of the blue sky and white clouds of Windows 9x. First, let's understand some basic concepts.
One is the BIOS (Basic Input/Output System), which is the low-level code that directly interacts with the hardware and provides the operating system with basic functions to control hardware devices. The BIOS includes system BIOS (commonly referred to as motherboard ROM-BIOS), graphics card BIOS, and BIOS of other devices (such as IDE controllers, SCSI cards, or network cards). Among them, the system BIOS is the main focus of this discussion because the startup process of the computer is carried out under its control. The BIOS is generally stored in ROM (Read-Only Memory), and these codes do not disappear even after the power is turned off or the system is shut down.
The second basic concept is the address of memory. In our computers, we usually install 32MB, 64MB, or 128MB of memory, and each byte of this memory is assigned an address for easy access by the CPU. The address range of 32MB is represented in hexadecimal as 0 to 1FFFFFFH. Among them, the lower-end 1MB of memory (0 to FFFFH) is very special because the initial 8088 CPU (Central Processing Unit) could only access a maximum of 1MB. This 1MB of memory is called the basic memory, while A0000H to BFFFFH is reserved for the video memory of the graphics card, and C0000H to FFFFH is reserved for the BIOS. The system BIOS generally occupies the last 64KB or slightly more space, while the graphics card BIOS is usually placed at CO000H to C7FFFH, the IDE controller BIOS at C8000H to CBFFFH.
Let's take a closer look at the startup process of the computer.