d4bk2bas
Understanding Your Personal Computer
PC 300GL
IBM
Understanding Your Personal Computer
PC 300GL
First Edition (November 1998)
Note:
Before using this information and the product it supports, be sure to read the general
information under Appendix, “Notices and Trademarks” on page 48.
The following paragraph does not apply to the United Kingdom or any country where such
provisions are inconsistent with local law: INTERNATIONAL BUSINESS MACHINES
CORPORATION PROVIDES THIS PUBLICATION “AS IS” WITHOUT WARRANTY OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Some states
do not allow disclaimer of express or implied warranties in certain transactions, therefore, this
statement may not apply to you.
This publication could include technical inaccuracies or typographical errors. Changes are periodically
made to the information herein; these changes will be incorporated in new editions of the publication.
IBM may make improvements and/or changes in the product(s) and/or the program(s) described in
this publication at any time.
This publication was developed for products and services offered in the United States of America.
IBM may not offer the products, services, or features discussed in this document in other countries,
and the information is subject to change without notice. Consult your local IBM representative for
information on the products, services, and features available in your area.
Requests for technical information about IBM products should be made to your IBM reseller or IBM
marketing representative.
 Copyright International Business Machines Corporation 1998. All rights reserved.
Note to U.S. Government Users — Documentation related to restricted rights — Use, duplication or
disclosure is subject to restrictions set forth in GSA ADP Schedule Contract with IBM Corp.
Contents
Overview
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vi
Chapter 1. Microprocessors and Memory
Microprocessors . . . . . . . . . . . . . . .
Microprocessor Speed . . . . . . . . . .
Microprocessor Cache . . . . . . . . . .
Microprocessor Bus . . . . . . . . . . .
Microprocessor Instructions
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Memory . . . . . . . . . . . . . . . . . . . .
Main Memory . . . . . . . . . . . . . . .
CMOS Memory . . . . . . . . . . . . . .
Flash Memory . . . . . . . . . . . . . . .
Cache Memory . . . . . . . . . . . . . .
Memory Organization . . . . . . . . . .
Physical and Virtual Memory . . . . .
Control Logic . . . . . . . . . . . . . . . . .
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1
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Chapter 2. Expansion-Bus
PCI-Bus . . . . . . . . . . .
PCI Interface
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PCI Performance . . . .
ISA-Bus . . . . . . . . . . .
Expansion-Bus Slots . . . .
Adapter Configuration . .
Plug and Play Adapters
Legacy Adapters . . . .
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Chapter 3. Video . . . . . . . . .
Monitors . . . . . . . . . . . . . . .
Resolution and Dot Pitch . . .
Scanning Characteristics . . . .
DDC Protocol . . . . . . . . . .
Power Management . . . . . .
Selecting a Monitor
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Using Monitor Controls . . . .
Using Screen Savers . . . . . .
Video Control . . . . . . . . . . .
AGP Video Controller
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Video Drivers . . . . . . . . . .
SVGA Mode . . . . . . . . . . . .
Special Characters and Languages
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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17
Chapter 4. I/O Features
 Copyright IBM Corp. 1998
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iii
Audio Ports . . . . . . . .
Serial Port . . . . . . . . .
Universal Serial Bus Ports
Parallel Port
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Keyboard Port . . . . . .
Keyboard Layout . . .
Languages . . . . . . .
Mouse Port . . . . . . . .
Monitor Port . . . . . . .
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Chapter 5. Storage Devices . . . . .
Diskette Drives . . . . . . . . . . . . .
Diskettes
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Identifying Diskettes . . . . . . . .
Handling and Storing Diskettes .
Labeling Diskettes . . . . . . . . .
Inserting and Removing Diskettes
Write Protecting Diskettes . . . .
Formatting Diskettes . . . . . . . .
Copying Diskettes . . . . . . . . .
Hard Disk Drives . . . . . . . . . . .
IDE . . . . . . . . . . . . . . . . . .
SCSI . . . . . . . . . . . . . . . . . .
CD-ROM Drives . . . . . . . . . . . .
Zip Drives
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35
Chapter 6. Security
Information Backup
Erased Files . . . . .
Computer Viruses .
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36
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37
Chapter 7. Software . . . . . . . . . . . . . . . .
Software Layers . . . . . . . . . . . . . . . . . . .
POST . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuration/Setup Utility Program . . . . . .
Operating Systems
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Device Drivers . . . . . . . . . . . . . . . . . . . .
Latest Level Device Drivers
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Device-Driver Types . . . . . . . . . . . . . . .
Video Device Drivers . . . . . . . . . . . . . .
Advanced Power Management . . . . . . . . . .
Advanced Configuration Power Interface (ACPI)
Application Programs . . . . . . . . . . . . . . . .
Protecting Your Software . . . . . . . . . . . . . .
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Chapter 8. Networking and System Management Features
Desktop Management Interface (DMI) . . . . . . . . . . . . .
iv
Remote Administration
DHCP and RPL . . . .
Wake on LAN . . . . .
Wake on Modem
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Wake on Ring . . . . .
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Appendix. Notices and Trademarks
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Notices
Trademarks . . . . . . . . . . . . . . .
Glossary
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v
Overview
This book provides information about microprocessors, memory, bus architectures,
input/output features, video, power management, ports, storage devices, security features,
and software. Not all features and capabilities described in this book are available on all
models.
For specific information on features of the PC 300GL and instructions on how to set up,
operate, install options, program, or maintain your computer, refer to the PC 300GL User
Guide that comes with your computer.
vi
 Copyright IBM Corp. 1998
Chapter 1. Microprocessors and Memory
The microprocessor-and-memory subsystem consists of components on the system board
that perform logical operations and calculations, control memory, and manage data-transfer
operations.
The devices and features that make up the microprocessor-and-memory subsystem are:
Ÿ Microprocessors and buses
Ÿ Memory and control logic
Microprocessors
The microprocessor controls most of the activity in your computer. Almost all information
passes through it, whether it is a keyboard stroke, data from a disk drive, or information
from a communication network. The microprocessor reads, changes, processes, and reroutes
information as needed.
Your computer comes with an Intel microprocessor that has a 64-bit internal data path
and integrated L2 cache. In addition, the microprocessor incorporates Intel MMX
technology. MMX technology boosts the performance of the microprocessor in processing
graphic, video, and audio data, thereby enhancing the performance of multimedia and
communications software. For information about the type and speed of the microprocessor
in your computer, view the System Summary screen displayed by the Configuration/Setup
Utility Program.
Another key feature of the microprocessor is that it includes system management mode
(SMM), which enables the microprocessor to control power used by peripheral devices and
other components. This makes processing more energy efficient and allows the system to
run cooler.
Microprocessor Speed
The microprocessor operating speed is referred to as clock speed and is measured in
megahertz (MHz)1. The design of the microprocessor determines the maximum clock speed
at which it can operate. A quartz crystal on the system board generates a pulse to the
microprocessor, causing the microprocessor to operate at a specific speed. A clock cycle is
the time that the microprocessor takes to perform instructions at a given clock speed. Clock
cycles are measured in nanoseconds (ns).
1
MHz only denotes internal clock speed of the microprocessor, not application performance; many factors affect application
performance.
 Copyright IBM Corp. 1998
1
Microprocessors can operate at two clock speeds: an internal speed for operations within the
microprocessor and an external speed for transferring data in and out of the microprocessor.
Microprocessor Cache
Both level-1 (L1) cache and level-2 (L2) cache are integrated with the microprocessor on the
system board. Cache is high-speed memory that stores information most often used by the
microprocessor. Integrated cache provides a performance increase over the external
placement of cache on the system board. Refer to “Cache Memory” on page 4 for more
information about cache memory.
Microprocessor Bus
The microprocessor has an external bus that connects it with main memory and control
circuits. This pathway, which is also called the processor bus or local bus, has the same bus
width as the microprocessor and operates at the same external speed.
Another computer bus, called the I/O bus or expansion bus, carries data and instructions
between the microprocessor bus and the computer peripherals. The width of the I/O bus is
32 bits. With advanced bus technologies, the speed of the I/O bus might approach that of
the microprocessor bus. With standard bus technology, however, the speed of the I/O bus
is much slower than that of the microprocessor bus. Refer to Chapter 2, “Expansion-Bus”
on page 8 for additional information.
Microprocessor Instructions
Data and instructions are necessary for each processing operation that the microprocessor
performs. Data and instructions are copied from memory into registers within the
microprocessor. Registers are also used to store the data that results from each processing
operation until the data is returned to memory.
The set of instructions that the microprocessor can perform determines whether the
computer can run a particular program. For example, programs written for 32-bit
computers require a microprocessor capable of performing 32-bit instructions.
Memory
Your computer uses several types of memory to store information. This section explains
memory concepts, types of memory, and how the types of memory are used.
Although a computer is a complex machine, the method it uses to store information is quite
simple. All information (data and instructions) is stored in a coded format made up of 0’s
and 1’s. Memory is a series of switches, with an open switch representing a 0 and a closed
switch representing a 1. Each switch represents the smallest unit of computer storage, a bit;
eight consecutive bits of storage equals a byte. Memory is allocated in kilobytes (KB),
megabytes (MB), and gigabytes where 1 KB equals approximately 1 000 bytes, 1 MB equals
approximately 1 000 000 bytes, and 1 GB equals approximately 1 000 000 000 bytes. In 1 MB
2
Microprocessors and Memory
of memory, the computer can store over 1 000 000 characters of information. The computer
organizes its memory by assigning an address to each byte as a point of reference. The first
address is 0, and the addresses increase sequentially. When information is written to
memory, the encoded character is placed at a specific address.
Main Memory
Main memory (or system memory) is a temporary workspace that is active only while your
computer is on. Any information placed in main memory is lost when you turn off your
computer. Therefore, if you create or modify information, you must save the data to
permanent storage, such as a diskette or hard disk.
The main memory in your computer uses synchronous dynamic random access memory
(SDRAM) modules for temporary storage of data and instructions. These SDRAM modules
are also known as dual inline memory modules (DIMMs). SDRAM is volatile memory, which
means that it must be constantly refreshed by an electric current. While the computer is
turned off, no current is supplied to the DIMMs, so no data is retained in SDRAM.
The DIMM connectors are located on the system board. For information about the type and
amount of main memory (or System Memory) in your computer, view the System Summary
screen displayed by the Configuration/Setup Utility Program.
CMOS Memory
Your computer also uses some nonvolatile RAM (NVRAM), also called complementary
metal-oxide semiconductor (CMOS) memory, for storing configuration and setup information.
Powered by a small battery, CMOS retains its contents while your computer power is off.
CMOS maintains information about:
Ÿ
Ÿ
Ÿ
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Ÿ
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Date and time
Security features
Power-management settings
Storage devices
Keyboard and mouse
ISA legacy configuration information
Plug and Play configuration information
Port assignments
I/O addresses and interrupts
Other selectable features
Flash Memory
To store programs for startup procedures and other internal operations, some computers
use read-only memory (ROM). These programs are encoded in ROM modules on the system
board. ROM is nonvolatile memory, which means that it retains its contents when the
computer is turned off. Generally, the contents of a ROM module cannot be modified.
However, electrically erasable programmable ROM (EEPROM) modules (also referred to as flash
memory) can be reprogrammed while they are in the computer.
Microprocessors and Memory
3
Your computer stores various system programs and data in flash memory so that they can be
updated whenever enhancements are made. Stored in flash memory are:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Basic input/output system (BIOS)
Power-on self-test (POST)
Configuration/Setup Utility program
Vital product data (VPD)
Processor update code
Cache Memory
Microprocessors can be so fast that main memory cannot respond to read and write requests
as quickly as the microprocessor can send them. In some cases, main memory imposes one
or more wait states on the microprocessor when it reads data from or writes data to
memory.
A wait state is a period of time (one microprocessor clock cycle) during which the
microprocessor suspends processing and waits for memory to respond to a read or write
operation (a memory I/O operation). The speed of a memory I/O operation is measured in
microprocessor clock cycles, so the microprocessor clock speed determines the minimum
time required for a memory I/O operation. Wait states cause the computer to operate less
efficiently than if the microprocessor were able to continue processing data during memory
I/O operations.
A method of reducing the need for wait states is by using cache memory, which improves
system performance by temporarily storing frequently used data and instructions in a cache.
A cache is a buffer between the microprocessor and main memory.
For information about the cache memory in your computer, view the System Summary
screen displayed by the Configuration/Setup Utility Program.
Level-1 Cache
Level-1 (L1) cache is determined by the type of microprocessor installed in your computer.
The L1 cache for the Intel microprocessors contain high-speed memory, known as static
random access memory (SRAM), that can respond to memory I/O operations without
imposing wait states on the microprocessor.
L1 cache memory is used to store the information most often used by the microprocessor.
This allows a microprocessor to handle information faster than if it had to use the system
memory each time it needed new information. During processing, the cache controller
copies other data and instructions into the cache, replacing data and instructions that are no
longer needed.
Performance is improved each time the microprocessor finds what it needs in the cache (a
cache hit). If it does not find what it needs (a cache miss), the cache controller must locate the
data or instruction in memory and copy it into the cache, while one or more wait states are
4
Microprocessors and Memory
imposed on the microprocessor. The cache controller manages the use of the cache so that
the number of cache hits far exceeds the number of cache misses.
Level-2 Cache
Your computer has level-2 (L2) cache memory integrated into the microprocessor. L2 cache
complements L1 cache to increase the probability of cache hits. If the microprocessor cannot
find what it needs in L1 cache, it searches L2 cache. If the data or instruction is not in
either cache, the cache controller locates it in main memory and copies it into both caches.
Cache Mode
The microprocessor frequently updates cache memory with changed data. Caches, in turn,
pass these changes to main memory.
When updating cache memory, your computer uses the write-back mode. In write-back
mode, the microprocessor updates the cache, then goes on to perform other functions while
the cache controller updates main memory.
Write-back mode provides better performance than write-through mode, which is a type of
cache architecture used in some other computers. In write-through mode, a microprocessor
updates main memory directly. Write-through mode is slower because the microprocessor
interacts directly with main memory, which is slower than cache memory.
Memory Organization
Operating systems are responsible for allocating memory space, assigning addresses, and
performing many other tasks associated with memory management.
DOS Memory Management
DOS organizes memory into the following types:
Ÿ Conventional
Ÿ Extended
Ÿ Expanded
Conventional memory is the first 1 MB of memory-address space. Of this, the first 640 KB is
available for use by DOS and application programs. Memory from 640 KB through 1 MB is
reserved as a work space for hardware devices and the BIOS.
Extended memory starts above the first 1 MB, appended to conventional memory. Use of
this space is dependent on the operating system and application programs. Not all
programs can use extended memory.
Expanded memory is controlled through an expanded memory specification (EMS) device
driver, such as the one provided with DOS. The EMS device driver is commonly known as
a memory manager. The EMS device driver uses part of the reserved area of conventional
memory as a work space, and the memory above the first 1 MB as a storage area. The
Microprocessors and Memory
5
memory above the first 1 MB is not written to or read from directly. It is broken into 16 KB
pieces called pages, or 64 KB pieces called frames, and is moved in and out of the reserved
area as needed. When a page or frame is moved into the reserved area, it can be read from
and written to as any other address in conventional memory.
Other Types of Memory Management
Operating systems such as Microsoft Windows 95, Windows 98, and Windows NT have
very sophisticated memory-management systems. These operating systems use a technique
called disk swapping or disk paging. If your computer does not have enough memory to meet
the needs of your active programs, these operating systems transfer the least-used
information from memory to the hard disk to make more memory available. When the
information on the hard disk is needed, it is exchanged with other information in memory.
Microsoft Windows 95, Windows 98, and Windows NT also use memory in another way.
These operating systems assign blocks of memory as virtual DOS machines (VDM). Each
VDM runs independently of the others, providing the same function as a separate computer
running DOS. With very few exceptions, these operating systems are fully compatible with
application programs written for DOS.
If you are using any of these operating systems, adding memory can increase the overall
performance.
Physical and Virtual Memory
Physical memory consists of all the addressable memory locations in the computer. Physical
memory is used to store such items as the operating system, video data, and instructions
and data the computer uses to run programs.
Virtual memory is memory that appears to be allocated to application programs. The
operating system uses a portion of the hard disk as virtual memory, swapping data and
instructions between the hard disk and physical memory.
Virtual memory makes multitasking possible. In a multitasking session, the memory
requirements of all the programs that might be running in the system at the same time can
far exceed the amount of physical memory that is available. The operating system allocates
virtual memory to meet the total memory requirements of each program and then manages
the available physical memory to meet the actual requirements. Thus, the amount of virtual
memory that is allocated can be much greater than the amount of physical memory installed
in the computer.
6
Microprocessors and Memory
Control Logic
The control logic consists of the modules on the system board that control access to main
and cache memory by the microprocessor and I/O devices. Control logic includes the
following devices and functions:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Audio-port controller and interface (some models only)
Bus-mastering IDE interface
Counters and timers
Direct memory access (DMA) controller
Diskette-port controller and interface
Interrupt controller
Keyboard and mouse port controller and interface
Memory (DRAM) controller
Microprocessor-interface control
Parallel-port controller and interface
PCI-bus interface
PCI-to-ISA interface
Power-management controller
Serial-port controller and interface
USB-port controller and interface
Microprocessors and Memory
7
Chapter 2. Expansion-Bus
This section gives an overview of the expansion-bus and explains how advanced buses can
improve performance.
A computer bus is a pathway of wires and signals that carries (or transfers) information
inside the computer; information includes data, addresses, instructions, and controls. The
microprocessor has an external bus, called the processor bus or local bus, that carries
information between the microprocessor and main memory. The processor bus has the
same bus width (64 bits) as the microprocessor and operates at the same external speed.
Another computer bus, the expansion-bus, carries information between the microprocessor or
memory and peripheral I/O devices. While processor-bus performance has improved
rapidly, improvements in expansion-bus performance have not equalled those of
microprocessors and some peripheral devices, such as video and disk controllers.
Regardless of how fast the microprocessor and other components are, data transfers
between them must pass through the expansion-bus.
Your computer has two expansion-buses: the ISA-bus and the PCI-bus. PCI is an advanced
expansion-bus standard developed by the computer industry to keep up with performance
improvements of processor buses and advanced peripheral devices. Although advanced
designs can match the performance of the microprocessor bus only up to a point, they do
achieve higher throughput by speeding up the expansion-bus and widening its data path.
PCI is intended to add to the capability provided by the ISA-bus.
PCI-Bus
An answer to the need for a higher-performance expansion-bus is the peripheral component
interconnect (PCI) bus. PCI architecture offers many features that improve expansion-bus
performance such as:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
8
Microprocessor independence
Industry-standard compatibility
Wider data path (32 bits)
Faster data-transfer rates
More efficient data-transfer methods
Enhanced peripheral-device performance
Automatic configuration
 Copyright IBM Corp. 1998
PCI Interface
The PCI-bus connects to the microprocessor bus through a buffered bridge controller. A
bridge translates signals from one bus architecture to another. PCI and ISA devices get all
their data and control information through the PCI controller. The PCI controller looks at
all signals from the microprocessor bus and then passes them to the ISA controller or to
peripheral devices connected to the PCI-bus. However, the PCI-bus is not governed by the
speed of the microprocessor bus. PCI can operate at speeds as fast as 33 MHz1, slow down,
or even stop if there is no activity on the bus, all independent of the microprocessor’s
operations. Microprocessor independence also makes PCI adaptable to various
microprocessor speeds and families and allows consistency in the design and use of PCI
peripheral devices across multiple computer families.
PCI Performance
One of the most significant features of PCI is its 32-bit data path, which is twice the width
of the ISA data path. With a 32-bit data path, the PCI-bus can transfer more information
per second than the ISA-bus, with its 16-bit data path. Also, PCI operates at higher speeds
of up to 33 MHz. Depending on the mode of operation and computer components used,
the PCI-bus can transfer data at speeds up to 132 MB per second. While many factors can
reduce practical performance, achieving just half or a third of the PCI maximum theoretical
throughput far exceeds the practical performance of the ISA-bus, which operates at 4 MB to
8 MB per second.
ISA-Bus
One of the most widely used and successful expansion-buses is the industry standard
architecture (ISA) bus, also called the AT bus. The ISA-bus is a 16-bit bus that operates at a
speed of 8 MHz. It can transfer up to 8 MB of data per second between the microprocessor
and an I/O device. Practical performance ranges between 4 MB and 8 MB per second.
The ISA-bus continues to be popular because so many adapters, devices, and applications
have been designed and marketed for it. Peripheral devices that do not require faster
throughput, such as fax modems, can use ISA. Also, ISA is adequate for users of DOS
applications in a stand-alone environment, or for DOS network requesters with moderate
performance requirements.
Although the ISA-bus is widely used and is suitable for many applications, it cannot
transfer data fast enough for today's high-speed microprocessors and I/O devices. For
example, the ISA-bus might not provide the performance needed by video devices and
applications with high resolution and high-color content. Also, ISA might not be capable of
handling the throughput required by some fast hard disk drives, network controllers, or
full-motion graphics controllers.
Expansion-Bus
9
Expansion-Bus Slots
If you want to add new capabilities to your computer, you can do so by installing optional
adapters. Your computer provides an ISA-bus expansion slot so you can take advantage of
the wide availability of ISA peripheral devices and applications. Also, PCI-bus expansion
slots allow you to connect high-performance devices to your computer, such as graphics,
SCSI, or LAN adapters.
There are four expansion slots in your computer. Three are dedicated PCI slots and one is a
dedicated ISA slot. These slots are grouped together on the system board.
The width of the expansion-bus determines the type of adapters the computer supports.
The dedicated ISA slots accept only 8-bit or 16-bit ISA adapters, and the dedicated PCI slots
accept only 32-bit PCI adapters. The width of the bus does not affect software
compatibility.
Adapter Configuration
When adding adapters, you might need to manually set a variety of switches on the
adapters. These switches control the assignment of computer resources such as interrupt
request (IRQ) lines, direct memory access (DMA) channels, and memory address ranges.
Determining how to set switches for (or configuring) these resources can be complex. A
better method of configuring adapters and devices called Plug and Play is used on your
computer to make expansion an easier task.
Plug and Play Adapters
Plug and Play is a configuration method that makes expanding your computer easier. Plug
and Play adapters are easier to set up because they are auto-configuring. A Plug and Play
adapter comes with built-in identification and configuration specifications set in memory on
the adapter to provide installation information to the computer during startup. This
information is interpreted by the computer's basic input/output system (BIOS), which supports
Plug and Play. The BIOS routines automatically configure the adapter as long as the
required resources are not already in use.
Adapters designed for PCI slots are Plug and Play devices. Many adapters designed for
ISA slots are not Plug and Play devices. If the adapter you are installing is not Plug and
Play, you must configure it manually.
10
Expansion-Bus
Legacy Adapters
Adapters that are not Plug and Play devices are referred to as legacy devices. The
Configuration/Setup Utility Program can help you manually configure legacy adapters.
The screens of the Configuration/Setup Utility Program show the resources typically
required by adapters:
Ÿ
Ÿ
Ÿ
Ÿ
Memory resources
I/O port resources
Direct memory access (DMA) resources
Interrupt resources
From these screens you can select available resources for the adapter you are installing.
Resources not currently being used by adapters already installed in your computer are set
to Available. When you install an additional legacy adapter, set the resources used to ISA
Resource. This enables the Plug and Play software to configure around legacy adapters,
then you can make the appropriate jumper or switch settings on the adapter. Also, if you
remove an ISA legacy adapter, set the resources it used back to Available. This frees up
those resources for future configurations. Refer to the adapter documentation for
information about required resources. Also, the refer to PC 300GL User Guide for more
information about using the Configuration/Setup Utility Program.
Expansion-Bus
11
Chapter 3. Video
This section describes the video features of your computer, including monitors, the graphics
controller, video modes, and other video features.
Monitors
Although there are various types of monitors, the most common distinguishing
characteristics are resolution, dot pitch, scanning rates, screen size, and color.
Resolution and Dot Pitch
The entire image on a monitor screen is made up of many tiny dots. These dots are called
picture elements or pels. The monitor resolution is described by the number of pels that fill
the screen in an array of horizontal rows and vertical columns. For example, the pels might
be arranged in a horizontal-by-vertical array of 640 x 480 pels to make up a typical screen
image. Higher resolutions, such as 800 x 600 or 1024 x 768 pels, mean more dots on the
screen. The benefit of higher resolutions is either displaying more information at one time
or displaying the same information with a sharper image.
Dot pitch refers to the space between the individual dots or pels. The inside of the monitor
screen is coated with light-emitting materials called phosphors. Color monitors use three
phosphors: red, green, and blue. The phosphor coating consists of dots arranged in a
red-green-blue pattern. The distance from the center of one phosphor dot to the center of
the next phosphor dot of the same color is the dot pitch. Dot pitch is measured in
millimeters, such as 0.28, 0.31, 0.39, and 0.41. In general, the monitor with the highest
resolution and finest dot pitch produces the sharpest image. A monitor with a fine dot
pitch, such as 0.28, produces sharper, better defined characters than a similar monitor that
uses a coarser dot pitch, such as 0.41.
Monitor characteristics can be very important. A computer used extensively for detailed
graphics might need a monitor that shows more colors, at a higher resolution and finer dot
pitch, than one used exclusively for word processing. For some applications, a
black-and-white (monochrome) monitor might work as well or better than a color monitor.
Scanning Characteristics
The phosphors on the inside of the monitor screen hold their brightness and color for a very
short time. Therefore, the image has to be scanned (redrawn) many times each second to
refresh the phosphors. The vertical refresh rate is the speed at which the image on the screen
is redrawn (or scanned). Refresh rates are specified in hertz (Hz).
The image is redrawn from top to bottom (or vertically). By the time the bottom pel rows
are drawn, the top rows are starting to fade. There are two ways of redrawing the image:
interlaced scanning and noninterlaced scanning. The interlaced method draws every other
12
 Copyright IBM Corp. 1998
row from top to bottom, then starts at the top to fill in the rows that were skipped on the
first pass. The noninterlaced method draws the complete image on each pass.
The vertical refresh rate affects the stability of the image on the screen. Monitors that have
a fast, noninterlaced refresh rate provide a very stable image with little or no detectable
flicker. Monitors with slower refresh rates tend to have more noticeable flicker. Flicker can
be particularly noticeable with white and other light-colored backgrounds. You can
minimize flicker by changing the colors you work with. Many programs allow you to select
colors.
Sensitivity to flicker varies from person to person. Noninterlaced flicker occurs when the
screen is redrawn at a rate that is slow enough to be detected by the human eye. Interlaced
flicker, or jitter, occurs when the pattern of pels in adjoining lines is very different, or when
an object on the screen is made up of alternating bright and dim lines.
Some application programs cannot reproduce all colors and use a technique called dithering
to combine two colors. For example, light red might be produced by alternating lines of
white and red. As the image is continually refreshed using the interlaced method, the red
lines are drawn on one pass and the white lines on the next pass. As a result, the light-red
object might appear to flicker while the rest of the image on the screen remains stable.
DDC Protocol
Potential problems with monitor flicker are reduced by operating a monitor at its highest
refresh rate. To simplify the job of setting the refresh rate, some monitors offer Plug and
Play capability using the VESA Display Data Channel (DDC) protocol. DDC is an industry
standard for passing configuration information between a monitor and a computer. Both
the monitor and the computer must have DDC capability.
Your computer supports the DDC2B protocol. With DDC, the computer can receive
configuration information sent from a DDC monitor. When you turn on the computer with
a DDC monitor connected, the monitor immediately starts sending its identification
information to the computer. This information, called Extended Display Identification Data
(EDID), includes a description of the monitor and its operational limits and timings. The
POST programs use the information from the monitor to automatically configure the video
controls to operate the attached monitor in its optimum mode. Thus, when the monitor
comes on, it is already set to the highest refresh rate that the monitor and graphics
controller can support.
Power Management
Power management reduces the power consumption of your computer when you are not
using it. A monitor with VESA Display Power Management Signaling (DPMS) support can
save a significant amount of energy and have a longer useful life. DPMS-compliant
monitors can be powered down in three modes: Standby, Suspend, and Off. The stages that
can actually be used, however, depend on the power-management capabilities of your
computer.
Video
13
In Standby mode, the monitor (and other devices) are switched to a reduced-power state if
you do not use your mouse or keyboard for a specified period. The devices remain in a
state of readiness and return to full power if you press a key or move the mouse. Suspend
further decreases monitor power, and Off reduces monitor power to its lowest level. Refer
to “Advanced Power Management” on page 42 for more information on power
management.
Check the documentation that comes with your monitor to see if your monitor is enabled
for power management. If you find no information about power management, your
monitor probably does not support this feature. If your monitor does not have DPMS
support, deactivate it in the power-management features of your software or use the
Configuration/Setup Utility Program to disable Display in all three levels of power
management. Even if you deactivate the display for power-management purposes, you can
still take advantage of screen savers. Refer to “Using Screen Savers” on page 15 for more
information.
Selecting a Monitor
The graphics controller installed in your computer is a high-performance, high-resolution
graphics accelerator and includes many performance-enhancing features for your operating
system environment. It has a built-in monitor connector. See “Video Control” on page 15
for more information. The graphics controller supports various SVGA monitor resolutions.
If you connect an SVGA monitor to your computer, you can take advantage of SVGA
resolutions such as 1024 x 768. However, the default resolution might be different for
certain software packages, especially if they are not SVGA-ready. Also, you might have to
install device drivers for certain software packages. Refer to the device-driver installation
instructions that come with the software on the IBM Software Selections CD for a list of
programs and the device drivers that they require.
To take full advantage of the video capabilities provided by your computer, use a
noninterlaced monitor capable of supporting high resolution and a fast refresh rate. Also,
the type of monitor you select depends on the software you use. Some applications are less
demanding than others.
Using Monitor Controls
A monitor has brightness and contrast controls for adjusting the image on the monitor
screen for maximum viewing comfort. On a new monitor, set the controls near their center
positions. Setting these controls to their maximum positions can decrease the useful life of
the monitor. As the monitor is used more, the image tends to become dimmer. You can
adjust the brightness and contrast controls to compensate for this condition. Monitors also
have additional controls for fine-tuning the screen image. Check the documentation that
comes with your monitor for more information on controls.
14
Video
Using Screen Savers
Leaving the monitor turned on for prolonged periods without changing the image can harm
the monitor. Depending on what is on the screen, the image might be permanently burned
into the phosphor coating or cause darkening of some areas of the screen.
With DPMS-enabled monitors, you can avoid this problem by using the power-management
features of your computer. Also, you can use a screen-saver program, which turns off the
video signal when the keyboard or mouse has not been used for a defined period. This
action results in a dark, blank, or animated screen. When you are ready to work with the
computer again, pressing a predefined key or a password restores the image to the screen.
Several companies produce screen-saver programs. For more information, contact your IBM
reseller or IBM marketing representative.
Video Control
Video control is the process of manipulating information into the desired format and sending
it to the monitor screen. Video control can be handled by the microprocessor or a separate
video or graphics controller. For graphics and window environments, video control
involves operations that handle a high volume of data and computations. These typically
require a high degree of speed. Moving a window from one location to another, dragging
an icon across the screen, and scrolling through a document are examples of such
operations.
AGP Video Controller
Your computer comes with an accelerated graphics port (AGP) video controller integrated
on the system board. It has a PCI-like interface dedicated to high-performance and 3D
graphical display applications. AGP provides a high bandwidth, direct connection to
system memory allowing the graphics controller to work independently of the
microprocessor and PCI adapters, resulting is in an increase in overall system performance.
Video Drivers
The graphics controller in your computer is supported by device drivers that are provided
on the IBM Software Selections CD that comes with your computer. Instructions for installing
the device drivers are also provided in README files on the IBM Software Selections CD. If
your computer has IBM-preinstalled software, the video device drivers have already been
installed on the hard disk. However, the information included in the device-driver
installation instructions will be helpful if you ever need to reinstall or update the device
drivers, or if you want to change the video resolution or color depth.
Video
15
SVGA Mode
Super video graphics array (SVGA) is a video standard for displaying text and graphic
images. Like other video standards, SVGA supports a variety of video modes. Video modes
are different combinations of resolutions, refresh rates, and colors defined by a video
standard for displaying text or graphics. SVGA provides higher-resolution graphics, faster
refresh rates, and more colors than previous video standards, such as video graphics array
(VGA). At the same time, SVGA video supports all standard VGA modes.
Your computer supports SVGA modes on a variety of monitors. Also, the SVGA modes on
your computer are in accordance with the specifications of the International Organization for
Standardization (ISO) 9241 Part 3, Visual Display Requirements. SVGA supports
reduced-flicker operation when used with noninterlaced monitors that meet ISO standards.
Some application programs require video device drivers to use SVGA modes. The device
drivers for your computer and instructions for installing them (README files) are provided
on the IBM Software Selections CD that comes with your computer. If your computer has
IBM-preinstalled software, the device drivers have already been installed on the hard disk
of your computer.
Some application programs provide their own video device drivers to take advantage of
SVGA modes. These device drivers are installed through a setup program built into the
application program. Setting up these applications to operate in SVGA modes might be
confusing because terminology for these modes is not consistent throughout the industry. If
you are uncertain about the terminology used by your application program, refer to the
documentation that comes with the application for additional information.
Special Characters and Languages
The video controller can display a variety of characters and languages. The language that is
supported depends on the code page loaded by your operating system.
You can find additional information about code pages in the documentation that comes
with your operating system.
16
Video
Chapter 4. I/O Features
Input/output (I/O) devices provide you with many ways of getting information into and
out of your computer. You can connect a variety of standard and optional devices to your
computer, including a monitor, keyboard, mouse, and printer.
This section includes information about I/O device connectors and also explains the
characteristics of some of the I/O devices.
Your computers system board includes connectors (or ports) for attaching I/O devices. An
I/O connector refers to the physical connector on the computer that allows you to connect an
external I/O device. These connectors are also called ports because they provide a
communication pathway into the computer for an I/O device. Each port is identified by a
number and an address that distinguishes it from other ports. No two ports can have the
same address. The terms I/O connector and I/O port are often used to mean the same thing.
Note: Your computer model might not include all of the I/O devices or connectors
described in this section. Refer to the PC 300GL User Guide for more specific
information.
Following are the system board I/O connectors that are available on the PC 300GL:
Ÿ Audio: (some models only)
Microphone in, Line out, Headphone out, and joystick/MIDI
Ÿ Serial
Ÿ Universal Serial Bus (USB)
Ÿ Parallel
Ÿ Keyboard
Ÿ Mouse
Ÿ Monitor
Audio Ports
The audio controller, integrated on the system board of some models, is SoundBlaster,
SoundBlaster Pro, and Windows Sound System compatible. It has three audio ports and a
joystick/Musical Instrument Digital Interface (MIDI) with 15-pin D-shell connector. Audio
support can be enabled or disabled using the Configuration/Setup Utility Program. Audio
ports provide you with the ability to play back and capture sound and music as well as the
ability to enjoy sound with multimedia applications. The joystick/MIDI connectors allow
attachment of a joystick or other Midi devices.
The ports are labelled:
Mic In
Connection for a microphone
Line Out
Connection for headphones or powered external speakers
 Copyright IBM Corp. 1998
17
Headphone
Connection for headphones or powered external speakers
joystick/MIDI
Connection for a joystick or a MIDI device
Note: When either headphones or speakers are connected to the headphone jack, the
internal computer speaker is disabled.
There might also be an internal speaker and connections on the system board for attaching
it to the CD-ROM.
To take advantage of the audio feature, some computers come with ViaVoice. ViaVoice is
continuous speech dictation and desktop navigation software available on CD-ROM. For
more information, see the READ1ST.TXT file in the appropriate language folder on the
ViaVoice CD-ROM.
Serial Port
Your computer comes with a serial port. The serial port is used to communicate with
devices such as printers, plotters, and modems designed for the serial interface. Some
modems are installed inside the computer; others are attached externally using the
serial-port connector. For example, you can connect an external modem to a serial port in
order to communicate with other computers over telephone lines.
The serial port transfers data one bit at a time at speeds ranging from 300 to 115 000 bits per
second (bps). The serial ports are 16550-UART (universal asynchronous
receiver/transmitter) compatible so they can support high-speed modems.
You can increase the number of serial ports by installing a serial adapter in one of the
expansion slots.
Operating systems and application programs often designate serial ports with the name
COM (communication). Many programs use COM1, COM2, COM3, and COM4 in their setup
commands or menus to identify serial ports. When setting up your applications, you might
have to identify the COM port to which a particular device is connected. Also, if you are
adding a serial adapter or modem, you might have to configure the adapter or modem for a
specific COM port. This might involve setting switches on the adapter or modem as well as
changing settings in the Configuration/Setup Utility Program.
The serial connector in your computer can use any of four available port settings, provided
that a different setting is used for each. The settings include the port address (in
hexadecimal) and the IRQ (interrupt request line), which determines how the microprocessor
responds to an interrupt from the serial port.
The four available port addresses are (in hex):
3F8
2F8
3E8
18
I/O Features
2E8
The available IRQs are:
IRQ
IRQ
IRQ
IRQ
IRQ
IRQ
IRQ
4
3
9
10
11
14
15
There is no direct relationship among the port connectors, the available port settings, and
the COM numbers. When you start the computer, the power-on self-test (POST) assigns
COM numbers to the port addresses that are actually in use at the time. POST goes down
the list of addresses sequentially to assign COM numbers to each address in use by a serial
device. If an address is not in use, a COM number is not assigned to it. POST assigns the
next available COM number to the next address in use, if any.
You can view the port address and IRQ settings for serial ports using the
Configuration/Setup Utility Program. You will not see the COM numbers on the setup
screens. To see port settings and COM assignments for all serial ports, you can use one of
the diagnostic programs available with the IBM-preinstalled software package.
Generally, you do not have to change serial-port settings. However, if you add a serial
adapter or use special hardware or software that causes a configuration conflict, you might
have to change port settings. If so, you can change the settings for the serial port using the
Configuration/Setup Utility Program. Refer to the PC 300GL User Guide for more
information about using the Configuration/Setup Utility Program.
To connect a device to your serial port, use a serial cable (purchased separately) to connect
the device to the serial connector at the back of the computer. Refer to the documentation
that comes with your I/O device for specific installation instructions.
Universal Serial Bus Ports
Universal serial bus (USB) is an emerging serial interface standard. The USB port is a
connector for devices that previously used serial, parallel, keyboard, mouse, and game
ports. USB technology uses Plug and Play features to determine what device has been
connected to the port. Each USB device is accessed by a unique USB address. A device
called a hub is used to convert a single USB connector into multiple attachment points. A
hub has multiple ports where devices can be attached. USB operates up to 12
megabits-per-second (Mbps) and supports a maximum of 127 devices.
I/O Features
19
Parallel Port
Your computer has a parallel-port connector as a standard, built-in feature. The parallel
port is most often used to communicate with a parallel printer, but it can also be used with
a variety of other parallel devices.
The parallel port transfers data 8 bits at a time, compared to the serial port, which transfers
data 1 bit at a time. The parallel port on the computer supports extended, high-speed
modes, which means that it can transfer data up to 10 times as fast as a standard parallel
port.
You can increase the number of parallel connectors by installing a parallel adapter in one of
the expansion slots.
Operating systems and application programs often designate parallel ports with the name
LPT (line printer). Many programs use LPT1, LPT2, and LPT3 in their setup commands or
menus to identify parallel ports. When setting up your applications, you might have to
identify the LPT port to which a particular device is connected. Also, if you are adding a
parallel adapter, you might have to configure the adapter for a specific LPT port. This
might involve setting switches on the adapter as well as changing settings in the
Configuration/Setup Utility Program.
Each parallel connector or adapter on your computer can use any of three available port
settings, provided that a different setting is used for each. The settings include the port
address (in hexadecimal) and the IRQ (interrupt request line), which determines how the
microprocessor responds to an interrupt from the parallel port.
The three available port addresses are (in hex)
378
278
3BC
The two available IRQs are:
IRQ 7
IRQ 5
There is no direct relationship among the three available port settings and the three LPT
numbers. When you start the computer, the POST assigns LPT numbers to the port
addresses that are actually in use at the time. POST goes down the list of addresses
sequentially to assign LPT numbers to each address in use by a parallel device. If an
address is not in use, an LPT number is not assigned to it. POST assigns the next available
LPT number to the next address in use, if any.
You can view the port address and IRQ setting for the built-in parallel port using the
Configuration/Setup Utility Program. However, you will not see the LPT number on the
configuration screen. To see port settings and LPT assignments for all parallel ports, you
20
I/O Features
can use one of the diagnostic programs available with the IBM-preinstalled software
package.
Generally, you do not have to change the parallel-port setting. However, if you add a
parallel adapter or use special hardware or software that causes a configuration conflict, you
might have to change the parallel-port setting. You can change the setting using the
Configuration/Setup Utility Program. Refer to the PC 300GL User Guide for more
information about using this program.
The parallel port can operate in five modes. One is a standard, unidirectional mode; the
other four are extended, bidirectional modes that provide additional function and higher
performance. Refer to the documentation that comes with printers and other parallel
devices to determine the appropriate parallel mode to use and the required device drivers.
Standard
This AT-compatible mode is the default mode. In this mode, the
parallel port is limited to writing information to the device attached to
it. You can use this mode with most IBM-compatible parallel printers.
Bidirectional
This PS/2-compatible mode is a bidirectional mode used for data
transfer to other computers and supported devices.
ECP
The extended capabilities port (ECP) mode is a high-performance,
bidirectional mode that uses direct memory access (DMA) for data
transfer to a high-speed printer or other devices.
EPP
The enhanced parallel port (EPP) mode is a high-performance,
bidirectional mode that has capabilities similar to ECP mode; the main
difference is that EPP data transfers are processor-initiated instead of
DMA. EPP supports the connection of up to eight external devices
such as hard disk drives, CD-ROM drives, tape drives, diskette drives,
and a printer to the parallel port. These devices can be connected to
each other in a daisy-chain arrangement, or they can be connected
through an external multiplexer. The attachment of multiple devices
requires device drivers supplied by the device manufacturers.
ECP/EPP
This mode combines the capabilities of the ECP and EPP modes.
Select this mode if you have both ECP and EPP devices connected to
the parallel port.
Note: ECP, EPP, and ECP/EPP modes are available only if the port address is hex 378 or
hex 278.
You can set these modes of operation for the parallel port using the Configuration/Setup
Utility Program. Refer to the PC 300GL User Guide for more information about using this
program.
To connect a parallel I/O device, such as a printer, use a parallel cable (purchased
separately) to connect the device to the parallel connector at the back of the computer.
Refer to the documentation that comes with your I/O device for specific installation
instructions.
I/O Features
21
Keyboard Port
The keyboard helps you communicate with your computer; the keyboard connects to the
keyboard-port connector on the back of the computer. Use your keyboard for the following:
Typing information
Performing application functions
Performing computer operations
Entering numbers with the numeric keypad
Ÿ
Ÿ
Ÿ
Ÿ
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Print
Screen
Scroll
Lock
SysRq
@
!
1
Tab
#
3
2
Q
$
4
W
%
5
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*
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7
6
R
T
(
9
8
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-
)
0
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O
+
=
Backspace
Insert
Num
Lock
Caps
Lock
Scroll
Lock
Break
Home
Page
Up
End
Page
Down
P
Delete
Paus e
Num
Lock
/
7
8
Home
*
-
9
Pg Up
+
C aps
Lock
Shift
A
S
Z
D
X
F
C
G
V
H
B
J
N
K
M
L
<
,
:
;
>
.
"
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4
5
1
2
6
Enter
Shift
End
3
Pg Dn
Enter
Ctrl
Ctrl
0
.
Ins
Del
104-Key Keyboard
Figure 1.
Keyboard Layout
The illustrations in this section show the 104-key keyboard. The keyboard includes the
following groups of keys:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Standard typing keys
Function keys
Special computer keys
Cursor keys
Numeric keypad
Function keys for Windows interface
Typing Keys
The layout of the typing keys is similar to that of a typewriter. The standard typing keys
are typematic; that is, they repeat typing the character as long as you hold them down. The
home row contains raised identifiers for the touch-typist. Unlike some typewriters, “1”
(one) and “l” (lowercase L) are not interchangeable on this keyboard.
The Shift key is used with the typing keys to produce uppercase characters and symbols.
When you press the Caps Lock key, a light turns on at the top right corner of your
keyboard. When the Caps Lock light is on, the alphabet keys you type appear on the screen
in capital letters. Caps Lock does not affect the number or punctuation keys.
22
I/O Features
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
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5
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4
3
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6
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7
(
8
)
9
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W
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T
Y
=
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Num
Lock
Caps
Lock
Scroll
Lock
Interr
Ins
Pag
ì
'
Paus a
Bloc
Num
/
7
8
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]
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I
O
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è
P
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+
|
\
Canc
Fine
Pag
9
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+
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ò
Z
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C
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B
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;
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M
4
5
1
2
6
à
_
-
:
.
3
Pag
Fine
Invio
Ctrl
0
Ctrl
'
Ins
Canc
Typing Keys
Figure 2.
The function of the Enter key is controlled by the program you are using. For example, a
word-processing program uses the Enter key to move the cursor to the beginning of the
next line. A spreadsheet program uses it to enter information into a specific cell or field.
Your operating system uses it to accept a command.
Some programs use the Ctrl and Alt keys in combination with the typing keys to perform a
specific operation. Refer to your application-program documentation for information about
the key assignments.
Function Keys
Function keys are arranged across the top of your keyboard. Use them to send instructions
to the software you are using. Think of them as shortcuts for doing routine tasks on your
computer.
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
%
5
$
4
3
#
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&
6
/
7
(
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)
9
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Num
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Caps
Lock
Scroll
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Interr
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Pag
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/
7
8
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9
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B
N
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;
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:
.
4
5
1
2
6
à
_
-
Fine
3
Pag
Invio
Ctrl
Ctrl
0
Ins
'
Canc
Function Keys
Figure 3.
Function-key tasks can vary from one application program to another. For example, you
press the F1 key in some application programs to display a help message; you might press
the same key in another program to display a list of files.
Some application programs use the Ctrl, Alt, and Shift keys in combination with the
function keys to define additional operations. Many programs provide a template that you
can place above the function keys. Refer to your operating-system and application-program
documentation for the definition of the function keys.
I/O Features
23
Special Computer Keys
The keyboard has several other keys that are not on a typewriter. These are Escape (Esc),
Control (Ctrl), Alternate (Alt), Insert (Ins), Delete (Del), Print Screen, Scroll Lock, and
Pause/Break.
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
3
#
Q
%
5
$
4
&
6
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7
(
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9
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=
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Num
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Caps
Lock
Scroll
Lock
Interr
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Pag
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Paus a
Bloc
Num
/
7
8
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]
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Pag
9
Pag
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;
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.
4
5
1
2
6
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Ctrl
Ctrl
0
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Special Computer Keys
Figure 4.
Your software controls these keys. It can disable them or modify their purpose. The
following list describes the most common uses of these keys.
Esc
Escapes from an operation, window, message, or program and returns
you to what you were doing previously.
Ctrl and Alt
Used with other keys to perform a specific operation defined by the
program in use. When two or more keys are used together to
perform a certain function, they are called combination keys. To use
combination keys, you simply hold them down at the same time. For
example, pressing Ctrl+Pause/Break stops the operation of most
programs.
Combination keys might work differently, depending on your
software.
24
Insert
Activates the insert mode, which allows you to insert information
between two existing characters. When you press insert again, you
return to the replace mode and write information over existing
characters.
Delete
Deletes a character or field.
Print Screen
Prints information on your screen to a printer. If the screen contains
graphic images, they might not be printed correctly.
Scroll Lock
Determines how you move through information. When you press the
Scroll Lock key, a light turns on at the top right corner of the
keyboard. With scroll locking on, the cursor can move through the
information on the screen. With scroll locking off, the cursor remains
stationary, and the information on the screen moves. Not many
programs use this function.
Pause/Break
Allows you to stop a program temporarily.
I/O Features
Cursor Keys
The Cursor keys are used to move the cursor (a flashing short line or small box) to various
positions on the screen.
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
3
#
Q
%
5
$
4
&
6
/
7
(
8
)
9
[
W
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=
0
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Num
Lock
Caps
Lock
Scroll
Lock
Interr
Ins
Pag
ì
'
Paus a
Bloc
Num
/
7
8
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]
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Canc
Fine
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9
Pag
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4
5
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2
6
à
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.
3
Pag
Fine
Invio
Ctrl
0
Ctrl
'
Ins
Canc
Cursor Keys
Figure 5.
Arrow keys
Moves the cursor up, down, right, or left on the screen, one space at a
time. Like the standard typing keys, the arrow keys are typematic;
that is, they keep repeating their function as long as you hold them
down.
Home
Moves the cursor to the beginning of a line or document.
End
Moves the cursor to the end of a line or document.
Page Up
Moves the cursor up one screen of information.
Page Down
Moves the cursor down one screen of information.
Numeric Keypad
The numeric keypad is arranged like a calculator. It is useful for entering numeric
information.
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
3
#
Q
%
5
$
4
&
6
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7
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8
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9
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Num
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Caps
Lock
Scroll
Lock
Interr
Ins
Pag
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7
8
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4
5
1
2
6
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3
Pag
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Ctrl
Ctrl
0
Ins
'
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Numeric Keys
Figure 6.
When the Num Lock light is on, the numbers marked on the keys are active. When the
light is off, the symbols marked below the numbers are active.
I/O Features
25
You can use the numeric keypad to:
Ÿ Activate the Num Lock key to enter numeric information.
Ÿ Deactivate the Num Lock key to control cursor movement.
Ÿ Enter special characters when used in conjunction with the Alt key. This is done by
holding down the Alt key while entering a numeric value on the keypad. The special
characters are determined by the code page used by your operating system. Code pages
vary by language.
Function Keys for Windows Interface
The 104-key keyboard provides three keys that are supported by Microsoft Windows NT,
Windows 95, and Windows 98. In order to use these keys with earlier versions of
Windows, you must use the appropriate device driver.
Esc
F1
F2
F3
F4
F5
F6
F 7
F8
F9
F10
F11
F12
Stamp
B lo c
S c o rr
RSist
!
1
\
"
2
%
5
$
4
3
#
Q
&
6
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8
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9
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Lock
Caps
Lock
Scroll
Lock
Interr
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Pag
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Num
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7
8
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Windows Interface Keys
Figure 7.
The two keys with the Windows logo are supported by the operating system and provide
system-level functionality. The third key, with an arrow pointing to a menu item, provides
a context menu when pressed, although other functions might be available for different
applications.
Languages
The operating system you use determines what characters can appear on your screen. Your
operating system provides programs that allow you to use characters from other languages.
Keyboard templates are also available to show you which keys on your keyboard
correspond to the characters of another language. Refer to your operating-system
documentation for additional information.
Mouse Port
Your computer has a mouse-port connector on the back panel for connecting a mouse. A
mouse is a pointing device that provides an easy method of moving the cursor or pointer
around the screen to make selections. Not all application programs support a mouse.
Graphics or object-oriented application programs and operating systems, such as Microsoft
Windows NT, Windows 95, and Windows 98 are much easier to use if you have a mouse.
26
I/O Features
Some mouse devices are designed for the round mouse connector on the back of your
computer, while others are designed for the D-shaped serial connector. Either type of
mouse will operate, provided you have the correct device driver installed.
Monitor Port
The monitor port allows you to connect a variety of video graphics array (VGA) or super video
graphics array (SVGA) monitors to your computer. Refer to “Selecting a Monitor” on
page 14 for information on monitors, and to “SVGA Mode” on page 16 for supported video
modes.
I/O Features
27
Chapter 5. Storage Devices
This section contains information about some of the data-storage devices available for your
computer. These devices enable you to expand the capacity of your computer.
The common types of storage devices that can be used in the computer are:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Diskette drives
Hard disk drives
CD-ROM drives
Tape drives
Zip drives
Each drive has a letter assigned to it. For example, if your computer has two diskette
drives, one is called drive A, and the other is called drive B. If you have only one hard disk
drive, it is called drive C. If you partition the drive, the partitions are named as if they were
separate drives: drive D, drive E, and so on.
The type and number of devices that you can have in your computer vary by computer
model. You can add internal storage devices if expansion bays are available. Refer to PC
300GL User Guide for more information on expansion space.
Diskette Drives
Your computer comes with a 1.44 MB diskette drive designed to use only 3.5-inch diskettes.
Optional diskette drives that support different sizes and capacities of diskettes are available
from your IBM marketing representative or IBM reseller.
Diskettes
You can use 3.5-inch diskettes in the diskette drive of your computer. If you want to use
5.25-inch diskettes, you must install a 5.25-inch diskette drive.
The information that follows will help you identify and use 3.5-inch diskettes.
Identifying Diskettes
The labeling on 3.5-inch diskettes is not consistent among manufacturers. Some diskettes
are labeled with the letters DD or HD to identify the diskette type; other diskettes might not
be labeled. However, the appearance of the lower-right corner of a 3.5-inch diskette always
can be used to identify the diskette type, as shown in the following illustrations.
28
 Copyright IBM Corp. 1998
3.5 Diske
2.0 MB tte
capacity
DD
No Window
1 MB Double Density (DD)
3.5 Diske
2.0 MB tte
capacity
HD
Window
2 MB High Density (HD)
Storage Devices
29
Handling and Storing Diskettes
Inside the protective diskette case is a flexible disk with a magnetic-sensitive coating. This
disk can be damaged by heat, dust, a magnetic field, or even a fingerprint. Use the
following guidelines when handling and storing diskettes.
Ÿ Data is stored on the magnetic surface of the diskette. On 3.5-inch diskettes, this surface
is protected by a plastic cover. If the cover is damaged, do not use the diskette. A
damaged diskette might damage the diskette drive.
Ÿ A protective slide on the top of a 3.5-inch diskette covers part of the magnetic surface.
The diskette drive moves this slide to read data from or write data to the diskette. Do
not move this slide, because fingerprints and dust can cause loss of data.
Top
Protective Slide
3.5 Diskette
2.0 MB
capacity
Diskette Label
Ÿ Never touch the magnetic disk itself.
Ÿ Keep diskettes away from magnets or devices that create a strong magnetic field, such
as electric motors and generators. Diskettes are sensitive to magnets found in television
sets, telephones, stereo speakers, and other such items. A magnetic field can erase the
data on your diskettes. Do not set diskettes on the monitor or use magnets to attach
notes to your computer.
Ÿ Do not store diskettes at high temperatures, low temperatures, or in direct sunlight.
Temperatures ranging from 4° to 53°C (39° to 127°F) are acceptable for 3.5-inch
diskettes. Keep diskettes away from heat. The plastic outer covering might warp,
damaging the diskette.
30
Storage Devices
Labeling Diskettes
Before using a diskette, label it so that you can identify the data stored on it. Labels usually
come in the package with the diskettes. Diskette labels can become a problem if you do not
apply them correctly. Loose edges or an excessive buildup of labels can prevent the
diskette from being inserted or ejected.
To prevent this problem, take the following precautions:
Ÿ Remove an old label before you apply a new one.
Ÿ Apply labels carefully to ensure that all edges are secure.
Ÿ Apply labels only to the front of diskettes. Do not place a label where it interferes with
the protective slide or covers an opening in the protective diskette case.
Inserting and Removing Diskettes
To insert a 3.5-inch diskette, hold the diskette with the label facing up and insert the end
with the protective slide first. Push the diskette into the diskette drive until the diskette
clicks into place.
To remove the diskette, press the eject button and slide the diskette out of the drive. Do
not remove the diskette while the in-use light is on.
Diskette-Drive
In-Use Light
Diskette
Eject Button
Storage Devices
31
Write Protecting Diskettes
It is possible to accidentally format a diskette or unintentionally write data to it. Important
information can be written over or lost. For this reason, it is a good idea to write protect
important diskettes. You can read data from a write-protected diskette, but you cannot
erase or change the data.
Most 3.5-inch diskettes have a write-protect switch that can be used to prevent data from
being written to or erased from the diskette. If a 3.5-inch diskette does not have a
write-protect switch, it is permanently write protected.
The write-protect switch is located on the back of 3.5-inch diskettes.
Write-Protect
Switch
Ÿ To allow writing to the diskette, slide the switch so the write-protect window is
covered.
Ÿ To prevent writing to the diskette, slide the switch so the write-protect window is open.
Formatting Diskettes
You can buy diskettes either formatted or unformatted. Formatted diskettes are ready to
use; unformatted diskettes must be formatted by your operating system before you can use
them. The format operation checks a diskette for defects and prepares it for storing data. If
data is already stored on the diskette, the format operation writes over it, and the data is
lost.
32
Storage Devices
The operating system FORMAT command specifies how to format a specific type of
diskette.
Attention: Always format diskettes to their correct capacity. Failing to do so might cause
unreliable results. Differences such as magnetic coatings, the thickness of the diskette
material, and the recording technique used all affect the formatting operation. Refer to your
operating-system documentation for detailed information on formatting diskettes.
The following table shows diskette types, their formatted capacities, and the drive type that
can be used with each diskette.
3.5-Inch Diskette Type
Formatted Capacity
Drive Type
1 MB (MF2DD)
2 MB (MF2HD)
720 KB
1.44 MB
1.44 MB
1.44 MB
Notes
1. MF2DD = Mini-floppy, two-sided, double density
2. MF2HD = Mini-floppy, two-sided, high density
3. If you are using DOS, use FORMAT A: /F:720 to format a 1 MB diskette in a 1.44 MB
drive.
Copying Diskettes
If you are using DOS, you can copy one or more files to or from a diskette using the COPY
command. Groups of files can be copied faster using the XCOPY command. Both COPY
and XCOPY can copy files to different types of diskettes. For duplicating a diskette, use the
DISKCOPY command. DISKCOPY requires that both the source diskette (the diskette you
copy from) and the target diskette (the diskette you copy to) be the same type.
Refer to your operating-system documentation for more information on copying diskettes.
Hard Disk Drives
Your computer comes with a hard disk drive preinstalled. The capacity of the drive varies
by model. An expansion bay is provided for installing additional drives. For information
about the hard disk drive in your computer, refer to the PC 300GL User Guide.
Hard disk drives have different types of interfaces, or controllers. The main function of the
interface is to transmit data to and from the hard disk drive. The different interface types
provide various degrees of performance and differ in the speed with which they can
transfer data between the hard disk drive and other system components. The most common
interface specifications used in IBM computers are discussed in the following sections.
Storage Devices
33
IDE
Your computer has a PCI-to-IDE interface that complies with the AT-attachment interface.
This interface includes the original IDE (ATA) interface with extensions for Ultra DMA-33.
The original IDE interface specification refers to a hard disk drive with a built-in controller
(as opposed to a hard disk drive with a separate controller). Two IDE connectors are
provided on the system board. One connector is designated as primary and the other as
secondary. Your computer system board can accommodate up to two IDE drives attached
to each connector. However, the PC 300GL only supports a total of three IDE devices.
When you connect two hard disk drives to the same ribbon cable, the two drives could
potentially send and receive data at the same time (because each drive has its own
controller). To prevent the drives from competing for priority, you must designate one
drive as the primary (master) drive, and the other as the secondary (subordinate) drive.
This is determined by switch or jumper settings on each hard disk drive. If only one hard
disk drive is attached to either the primary or secondary IDE connector, it must be
designated as the master drive.
SCSI
Some computers have a SCSI (small computer system interface) hard disk drive connected to
an optional SCSI adapter. SCSI can be faster than IDE, particularly when used with a
multitasking operating system, such as Microsoft Windows 95, Windows 98, and Windows
NT. With SCSI, instructions can be sent concurrently to every drive in the system, and the
drives can then execute these instructions simultaneously. This is not possible with IDE.
SCSI is well suited for computers in which expandability is important.
CD-ROM Drives
An IDE compact disc-read only memory (CD-ROM) drive uses a removable compact disc (CD)
that stores various formats of audio and video information. A CD-ROM drive can play
back or read from a CD, but it cannot write information to it. The information on the CD
can be heard or viewed, but not changed or updated as it can on a diskette, hard disk, or
tape.
CD-ROM technology offers quick access to enormous amounts of information. Diskettes,
hard disks, and tapes are magnetically recorded. CDs are optically recorded at a much
higher density. CD-ROM drives use industry-standard 12 cm (4.75 in) CDs with formatted
capacities of approximately 650 MB of data. CDs are used for music, voice, animated
graphics, multimedia, education, software distribution, and many other applications.
To hear music or voice from a CD, you can utilize the built in speaker or, if your model has
an audio controller, connect headphones or powered speakers.
Some models come with an IBM-preinstalled CD-ROM drive.
34
Storage Devices
Zip Drives
Some computers come with a preinstalled internal Zip drive. A Zip drive is a high-capacity
disk drive that uses a removable disk that is slightly larger and about twice as thick as a
conventional 3.5-inch floppy diskette. The Zip disk has a capacity of 100 MB of data. They
have become very popular for backing up hard disk drives or transporting large files.
Storage Devices
35
Chapter 6. Security
This section provides information about the security features of your computer.
Security is important for protecting your computer and the data stored in it. If you use
your computer in a public environment, such as an office, you might want to protect the
computer and data by using one or more of the security features available to you.
Some of the features include:
Ÿ A lockable cover using a customer supplied padlock to help secure computer hardware
components
Ÿ A u-bolt and a lockable cable can be installed to secure the computer to a desk or table.
Ÿ A power-on password to help prevent unauthorized use of the computer
Ÿ An administrator password to authorize computer-setup changes
Ÿ An unattended start mode to enable the computer to operate without input from the
keyboard or mouse
Ÿ A selectable startup sequence to prevent use of unauthorized programs to bypass
security controls
Ÿ Selectable disabling of diskette and IDE drives to prevent unauthorized use
Ÿ I/O port control to disable input and output functions of the serial and parallel ports
and their attached devices
The use of some features also depends on your operating system and network software.
For detailed information about using these security features, see the PC 300GL User Guide.
While the security features can offer a good deal of protection for your computer and data,
there are limitations, depending on the operating environment. For example, these features
cannot authenticate or identify the adapter that attaches the computer to a LAN, and they
cannot prevent outside persons or computers from gaining access to the computer, if it is
equipped with a modem set to the automatic answering mode.
A major aspect of your security plan is protecting the information (data) stored in your
computer. Some of the considerations of data security are:
Ÿ Backup and recovery
Ÿ Erased files
Ÿ Computer viruses
36
 Copyright IBM Corp. 1998
Information Backup
Most of the information stored on a hard disk is contained in data files. Data files contain
the information you put in the computer, such as letters and reports.
You can lose data files from your hard disk for a variety of reasons. Security violations,
improper handling during a move, or computer viruses can destroy stored information. To
avoid losing information, make copies of the data files using storage devices such as
diskette drives, tape drives, or Zip drives. Also, if you are connected to a LAN, you might
be able to back up information to another computer on the LAN. Backup copies can save
you time and money recovering files accidentally erased from a hard disk or lost when a
hard disk drive fails.
Back up your hard disks on a regular basis (daily, weekly, or monthly depending on how
often the information changes). Also, back up the hard disk before moving the computer.
Backup procedures differ from one operating system to another.
Erased Files
Erasing a file from a diskette or hard disk does not necessarily destroy the file. With the
proper software tools, someone might be able to restore all or part of an erased file. An
erased file, therefore, might be a security exposure if you sell your computer or give
someone a diskette that once contained confidential information.
The standard operating-system format commands do not remove all information from a
hard disk. Low-level format programs are used for this purpose and are available from a
number of software manufacturers.
Diskettes are a little different. An operating-system format command writes a repeated
pattern over the entire surface of the diskette. As a result, any information that was on the
diskette becomes unreadable.
Depending on the type of information stored, you might require additional safeguards.
Computer Viruses
A computer virus is a program (or instructions hidden within a program) that can “infect”
files and programs on your computer. Unlike most other programs, viruses are typically
designed to spread themselves. Some viruses can display a message or cause erratic screen
behavior. Others are destructive, erasing or damaging files, or overloading memory and
communication networks.
Viruses are difficult to detect. Many stay inactive until triggered by a specified event such
as a date, command, or some other operation. Some are activated when an infected
program is started a specified number of times. When the symptoms of the virus appear, it
Security
37
might be difficult to determine if the problem is a hardware failure, a software problem, or
a virus in action.
Viruses are generally spread unknowingly from computer to computer when programs are
copied or exchanged. If you don't know where a program came from, be careful. Most
reputable bulletin-board owners and distributors of programs scan their files to guard
against viruses and maintain records identifying program owners. You can take steps to
protect your information by using a virus-scan program.
38
Security
Chapter 7. Software
Software includes a variety of instructions, programs, utility programs, and tools that enable
your computer to do what you want it to do.
Software Layers
Several layers of software work together to make your computer work.
System programs are the basic layer of software built into every computer. They include the
POST, BIOS, and Configuration/Setup Utility programs. Power-on self-test (POST) is a set of
tests and procedures performed every time you turn on your computer. Basic input/output
system (BIOS) is a layer of software that translates instructions from other layers of software
into electrical signals that the computer hardware can understand. Except for a short
message on your screen when you turn your computer on, you rarely have much direct
involvement with BIOS. You can use the Configuration/Setup Utility Program to set up
your computer for different features and options.
Other software used by your computer includes: device drivers, which support a specific
type of hardware device; and Advanced Power Management (APM), which allows the
computer to conserve energy, or allows the computer to turn on when it is unattended.
An operating system is the layer of software that manages all computer operations by
directing the flow of information to and from the various parts of the computer. The
operating system interprets instructions from you and your application programs and
directs these instructions to the BIOS. Your computer needs an operating system to run
application programs.
Application programs are the highest layer of software. An application program allows you
to do specific work, such as word processing, desktop publishing, or financial accounting.
These are the programs you use to get work done on your computer. Some application
programs, called tools or utility programs, are designed for very specific tasks such as
configuring the computer, using a feature, or testing the computer. And, of course, there
are games to keep you entertained.
Your software might have been preinstalled for you, or you might have to install it yourself.
If not preinstalled, your software package usually contains program diskettes, CDs, and
instruction manuals. Refer to the information provided with your software for installation
and operating instructions.
 Copyright IBM Corp. 1998
39
POST
Each time you turn on your computer, power-on self-test (POST) is automatically run. POST
programs are stored in flash memory along with the BIOS and the Configuration/Setup
Utility Program. Functions of POST are:
Ÿ
Ÿ
Ÿ
Ÿ
Ÿ
Test the computer hardware and subsystems
Update the computer configuration
Load the BIOS into system memory
Load the operating system into system memory
Report problems
While POST is running, the computer displays an IBM screen with several messages and
prompts. A password prompt asks you for a password, if you have set a password with
the Configuration/Setup Utility Program. Other prompts allow you to access the
Configuration/Setup Utility Program or escape from POST. When POST is successfully
completed, the computer proceeds to the first screen of your operating system or application
program. If problems or configuration changes are found, POST displays error codes and
messages. Refer to the problem-solving section of the PC 300GL User Guide for explanations
of error messages and actions you can take to correct problems.
Configuration/Setup Utility Program
Most computer devices (storage devices, ports, adapters, and other optional features) have
programmable settings. Your computer has a special type of nonvolatile memory (called
CMOS) where it saves these settings. This memory is kept active by a battery so the
settings are not lost when you turn off the computer. Each time you turn on the computer,
a POST routine copies the configuration settings from memory to the various devices to get
them ready for operation. If the battery fails, the settings in memory are lost, and the
Configuration/Setup Utility Program automatically reconfigures built-in devices.
When you add or remove hardware from your computer and restart the computer, the
configuration settings must be updated. In most cases, the BIOS detects the change in
hardware and automatically updates the configuration. In other cases, you might need to use
the Configuration/Setup Utility Program to manually update the configuration. Either way,
the computer displays a configuration-error message on the screen and gives you the option
of accessing the Configuration/Setup Utility Program. You must enter the
Configuration/Setup Utility Program and either save the automatic update or manually
change the new configuration settings. For more information on using the
Configuration/Setup Utility Program and saving configuration changes, see the PC 300GL
User Guide.
40
Software
Operating Systems
An operating system is a complex collection of utility programs and device drivers that
control what a computer does. It is the operating system that enables a computer to accept
information from a keyboard, display it on a monitor, print it, and save it on a disk. The
operating system has built-in routines for performing input and output operations, such as
reading and writing disk files. When an application program gives a command to the
operating system to save a file, the operating system communicates with the BIOS to
transfer the file from memory to disk.
Just as the BIOS defines how the hardware works, the operating system defines how
software works by establishing a set of rules all software must follow. For example, the
operating system defines how files are named, what commands can be used, and how
memory is organized. Your computer is designed to use a variety of operating systems to
meet many different needs.
Device Drivers
Device drivers are programs that support a specific type of hardware device, such as a
printer or high-resolution monitor. These programs provide instructions that allow the
computer to interact with the device or take advantage of the special features of a device.
Device drivers are necessary because the BIOS cannot be large enough or current enough to
contain all the code needed to control every hardware device. If your computer has
IBM-preinstalled software, the device drivers might be included with your operating system
or application programs. Also, some device drivers are located on the IBM Software
Selections CD. Hardware optional features also might include diskettes that contain the
device drivers you need to make the optional features work.
Latest Level Device Drivers
The latest device drivers are always available on the World Wide Web or from the IBM
Personal Systems Group Bulletin Board System (BBS). For more help information, refer to
the PC 300GL User Guide.
The IBM PC Company Bulletin Board System (BBS) can be reached 24 hours a day, 7 days a
week. Modem speeds of up to 14 400 baud are supported. Long distance telephone charges
might apply. To access the PC Company BBS:
Ÿ In the U.S., call 1-919-517-0001.
Ÿ In Canada:
– In Halifax, call 902-420-0300.
– In Montreal, call 514-938-3022.
– In Toronto, call 905-316-4255 or 416-956-7877.
– In Vancouver, call 604-664-6461 or 604-664-6464.
Software
41
– In Winnipeg, call 204-934-2735.
For the latest device drivers, visit the following page:
http://www.pc.ibm.com/support
Device-Driver Types
Device drivers fall into two general categories: application-specific and device-specific.
Application programs load application-specific device drivers into memory. These device
drivers stay in memory while the application is running, and generally are cleared from
memory when you exit from the application.
Device-specific drivers are loaded into memory each time you turn on the computer. Some
device drivers check for the presence of a device each time you turn on the computer. If
the device it supports is not attached or is not turned on, the device driver is not loaded
and might generate an error message. After they are loaded, device-specific drivers stay in
memory. For more information about loading device drivers, refer to your
operating-system documentation and the documentation that comes with your hardware or
device drivers.
Video Device Drivers
Video device drivers are provided on the IBM Software Selections CD that comes with your
computer. If your computer has IBM-preinstalled software, video device drivers are already
installed on the hard disk of your computer. (However, note that DOS video device drivers
might need to be installed.)
Advanced Power Management
Conserving energy is important for your computer and is also environmentally friendly.
For both of these reasons, your computer provides energy-saving software, collectively
called Advanced Power Management (APM).
The following are the APM features included with your computer:
Ÿ APM BIOS is important if your computer uses an operating system that supports
APM-capable computers. When this setting is disabled, all APM BIOS support is
disabled.
Ÿ Automatic Hardware Power Management allows you to reduce or suspend power to
components of the computer after a preset time of inactivity is reached (a SCSI hard
disk drive is unaffected by this feature). For more information on setting and using this
feature, see the PC 300GL User Guide.
Ÿ Activity Monitor allows you to select which devices are monitored to determine if the
system should enter or exit the low power state. Not all operating systems support this.
42
Software
Refer to your operating system documentation to determine if the Activity Monitor is
supported.
Ÿ Automatic Power On enables the computer to turn on when it is unattended. Optional
hardware and software is needed for some features of Automatic Power On. For more
information about Automatic Power On, see the PC 300GL User Guide.
Attention: If a device, such as a monitor, does not have power-management capabilities, it
might be damaged when exposed to a reduced-power state.
Advanced Configuration Power Interface (ACPI)
ACPI is a BIOS mode that allows the operating system to control the power management
features of your computer. Not all operating systems support ACPI BIOS mode. Refer to
your operating system documentation to determine if ACPI is supported.
Application Programs
Application programs provide the tools necessary to complete a specific type of job, such as
editing text or preparing a spreadsheet. A variety of programs are available to aid you in
generating reports, working with numbers, using graphics, and performing many other
personal and business functions.
Many application programs are commercially available for your computer. After you
determine the types of application programs you need, select programs that will work with
your computer. Most program packages list the computer equipment you need to run the
program. Read the package carefully and look for the following information:
Computer Type
Make sure the box is labeled for IBM or IBM-compatible computers.
Diskette Size
Your computer has a 3.5-inch diskette drive. Make sure the
package contains 3.5-inch diskettes. If you installed an optional
5.25-inch diskette drive, you can use 5.25-inch diskettes also.
CD-ROM Support
If your computer has a CD-ROM drive, you can purchase
application programs that are available on CDs.
Video Support
Your computer has an SVGA graphics controller that also supports
video graphics array (VGA) standards.
Protecting Your Software
Under normal circumstances, there is little you can do to damage your software; however,
accidents can happen. If you establish good habits when using your computer, you are less
likely to experience problems.
Software
43
Your computer might come with the operating system and other software already installed
on the hard disk drive. The operating system might fail if you modify operating system
files incorrectly or if you try to install software that is not designed to operate on your
computer. Back up your operating system and other software so that you can more easily
recover from an operating system or hard disk drive failure. For instructions on how to
back up the operating system programs, refer to the documentation for your operating
system.
Also, make backup copies of any original software diskettes. Using the backup copy can
prevent damage to the original diskettes. Your operating-system documentation gives
instructions for making backup copies.
44
Software
Chapter 8. Networking and System Management Features
This section contains information about the networking features available on your computer.
A network consists of computers linked together so that they can share resources, such as
files, programs, and peripherals. The simplest form of a network consists of two computers
connected through their serial or parallel ports. This type of network might be used by an
individual to transfer files between a laptop computer and a desktop computer.
Other networks are larger and typically consist of computers designated as servers and
workstations. Servers provide shared resources (they store and retrieve shared data files) for
computers linked to the network. They typically have fast processors and large,
high-capacity disk drives that operate unattended. In contrast, workstations, often referred
to as clients, are computers used by individuals and do not provide shared resources for an
entire network.
Some computers come network-ready with a preinstalled Ethernet adapter. This adapter
provides a high-performance network connection with an 8-conductor, Rj-45, unshielded
twisted pair (UTP) connector. For computers with IBM-installed software, device drivers for
this adapter are on the hard disk; for some adapters, device drivers are also provided on the
IBM Software Selections CD that comes with your computer. For instructions on connecting a
network cable to your computer, refer to the PC 300GL User Guide. For information on
configuring your computer to work with a network, consult your network administrator.
When your computer is linked to a network, you can take advantage of the following
features:
Ÿ Desktop Management Interface (DMI)
Ÿ Dynamic Host Configuration Protocol (DHCP) or Remote Program Load (RPL)
Ÿ Remote Administration
Ÿ Flash on LAN
Ÿ Wake on LAN
Ÿ Wake on Modem
Ÿ Wake on Ring
Desktop Management Interface (DMI)
DMI consists of software that enables network administrators to remotely monitor and
control your computer in a network environment. DMI can be used to remotely track many
types of information about computers, including serial numbers, memory attributes,
product-specific characteristics of installed peripherals, temperature, and operating-system
configuration information. This information can be accessed using a DMI browser. DMI
 Copyright IBM Corp. 1998
45
browsers are provided by all major operating systems and all major LAN management
packages (including Netfinity and LANClient Control Manager).
Remote Administration
When this feature is enabled and you are connected to a network, the system programs in
your computer can be updated remotely by a network server. If you have set an
administrator password for your computer, it does not have to be entered by the server.
Consult your network administrator for information on setting up your network server to
perform POST/BIOS updates.
DHCP and RPL
DHCP (Dynamic Host Configuration Protocol) and RPL (Remote Program Load) enable a
network administrator to control your computer. The DHCP feature makes it possible for a
DHCP server on your intranet2 to assign an IP (internet protocol) address to your computer
so that a startup image can be loaded from the server. The DHCP server must be one that
supports BOOTP (Boot Protocol) on your intranet using software such as the Intel LAN
Desk Configuration Manager. Your computer requires network management software, such
as the LANClient Control Manager.
If you use RPL in conjunction with software such as LANClient Control Manager, you can
use a feature called Hybrid RPL. Using LANClient Control Manager, you set up your
computer by installing hybrid images (or files) on the hard disk. Then, each time the
computer starts from the network, LANClient Control Manager recognizes your computer
as a Hybrid RPL client and a bootstrap program is downloaded to your computer. This
bootstrap program is small and helps prevent network congestion. Working from the
hybrid images, the bootstrap program initiates the startup process from the hard disk of
your computer. An advantage to Hybrid RPL is that the network load associated with
standard RPL is avoided.
Wake on LAN
Some models of the PC 300GL have a LAN adapter installed that is designed to use Wake
on LAN, an IBM-developed technology that allows your computer to be turned on remotely
by a network server. When Wake on LAN is used in conjunction with network
management software, such as Netfinity Version 4 (included on the IBM Software Selections
CD that comes with your computer), functions such as data transfers and software and
device driver updates can be performed remotely on your computer and all other
computers on your network that are enabled for Wake on LAN. To avoid interruptions and
2
46
An intranet is a private network that conforms to the same protocols as the internet, but is contained within an organization.
The intranet contains one or more servers that provide services to the workstations on the private network. Some intranets
are also connected to the Internet.
Networking and System Management Features
help increase productivity, these updates can be done after normal working hours or on
weekends when LAN traffic is at a minimum.
Wake on Modem
Your computer might have an internal modem installed that is designed to use the Wake on
Modem feature. This feature allows your computer to be turned on remotely when a
modem ring is detected. In BIOS this is referred to as Modem Ring Detect. When Wake on
Modem is used in conjunction with network management software, such as Netfinity
Version 4 (included on the IBM Software Selections CD that comes with your computer),
functions such as data transfers and software and device driver updates can be performed
remotely on your computer. To avoid interruptions and help increase productivity, these
updates can be done after normal working hours or on weekends when telecommunication
traffic is at a minimum.
Wake on Ring
Your computer might have an external modem attached to the serial port. The Wake on
Modem feature allows your computer to be turned on remotely when a modem ring is
detected. In BIOS this is referred to as Serial Port Ring Detect. When Wake on Ring is used
in conjunction with network management software, such as Netfinity Version 4 (included on
the IBM Software Selections CD that comes with your computer), functions such as data
transfers and software and device driver updates can be performed remotely on your
computer. To avoid interruptions and help increase productivity, these updates can be
done after normal working hours or on weekends when telecommunication traffic is at a
minimum.
Networking and System Management Features
47
Appendix. Notices and Trademarks
Notices
References in this publication to IBM products, programs, or services do not imply that IBM
intends to make these available in all countries in which IBM operates. Any reference to an
IBM product, program, or service is not intended to state or imply that only that IBM
product, program, or service may be used. Subject to IBM’s valid intellectual property or
other legally protectable rights, any functionally equivalent product, program, or service
may be used instead of the IBM product, program, or service. The evaluation and
verification of operation in conjunction with other products, except those expressly
designated by IBM, are the responsibility of the user.
IBM may have patents or pending patent applications covering subject matter in this
document. The furnishing of this document does not give you any license to these patents.
You can send license inquiries, in writing, to:
IBM Director of Licensing
IBM Corporation
500 Columbus Avenue
Thornwood, NY 10594
U.S.A.
Trademarks
The following terms are trademarks or registered trademarks of the IBM Corporation in the
United States or other countries or both:
AT
IBM
LANClient Control Manager
Netfinity
ViaVoice
Wake on LAN
The following terms are trademarks of other companies:
Intel and MMX are trademarks or registered trademarks of Intel Corporation.
Microsoft, Windows, and Windows NT are trademarks or registered trademarks of
Microsoft Corporation.
Other company, product, and service names may be trademarks or service marks of others.
48
 Copyright IBM Corp. 1998
Copyright International Business Machines Corporation 1998. All rights reserved.
Note to U.S. Government Users — Documentation related to restricted rights — Use,
duplication or disclosure is subject to restrictions set forth in GSA ADP Schedule Contract
with IBM Corp.
49
Glossary
This glossary includes terms and definitions from
the IBM Dictionary of Computing, New York:
McGraw-Hill, copyright 1994 by International
Business Machines Corporation. Copies may be
purchased from McGraw-Hill or in bookstores.
A
adapter. A printed circuit board that modifies the
system unit to allow it to operate in a particular
way.
address. (1) A value that identifies a register or a
particular part of storage. The value is represented
by one or more characters. (2) The location in the
storage of a computer where data is stored. (3) To
refer to a specific storage location by specifying the
value that identifies the location.
address bus. The path used for the transmission of
address information in a computer.
AGP. accelerated graphics port
analog. (1) Pertaining to data consisting of
continuously variable physical quantities.
(2) Contrast with digital.
application program. (1) A program that is specific
to the solution of an application problem. (2) A
program written for or by a user that applies to the
user's work, such as a program that does inventory
control or payroll.
architecture. See computer architecture.
audio controller. An audio controller receives input
from a microphone or input line, digitizes the signal,
and stores it in the computer. The controller can
play back the digitized signal to an external speaker
or headphones.
auxiliary storage. Addressable storage, other than
memory, that can be accessed by means of an
input/output channel; for example, direct access
storage devices or magnetic tape.
50
B
back up. To copy information, usually to diskette
or tape, for safekeeping.
backup. Pertaining to a system, device, file, or
facility that can be used in the event of a
malfunction or loss of data.
baud rate. A number representing the speed at
which information travels over a communication
line. The higher the number, the faster
communication occurs.
bay. An area within a personal computer that
provides space and physical support for storage
devices.
binary. Pertaining to a system of numbers to the
base 2; binary digits are 0 and 1.
BIOS (basic input/output system). Code that
controls basic hardware operations such as
interactions with diskette drives, hard disk drives,
and the keyboard.
bit. Either of the digits 0 or 1 when used in the
binary numeration system.
buffer. (1) A routine or storage used to
compensate for a difference in rate of flow of data,
or time of occurrence of events, when transferring
data from one device to another. (2) A portion of
storage used to hold input or output data
temporarily.
bus. One or more conductors used for transmitting
signals, data, or power. See also address bus, data
bus, and expansion bus.
bus master. A device or subsystem that controls
data transfers between itself and a slave.
byte. A string that consists of a number of bits,
usually 8, that are treated as a unit and represent a
character.
 Copyright IBM Corp. 1998
C
cable. The physical medium for transmitting
signals; it includes copper conductors and optical
fibers.
cache. A buffer storage that contains frequently
accessed instructions and data; it is used to reduce
access time.
CD. Compact disc. A disc, usually 4.75 inches in
diameter, from which data is read optically by
means of a laser.
CD-ROM. Compact disc-read only memory.
High-capacity read-only memory in the form of an
optically read compact disc. See also CD and ROM.
central processing unit (CPU). (1) The section of
the microprocessor where arithmetic and logical
operations are performed, and instructions are
decoded and executed. (2) The functional unit that
controls the operation of the computer.
chip set. An integrated circuit or a set of integrated
circuits that provide hardware support for a related
set of functions, such as the generation of video.
clock. A device that generates periodic, accurately
spaced signals used for purposes such as timing,
regulation of the operations of a processor, or
generation of interrupts.
clock cycle. For a microprocessor, the amount of
time that the microprocessor takes to perform at a
given clock speed. Clock cycles are measured in
nanoseconds (ns).
clock speed. For a microprocessor, the operating
speed of the microprocessor. Clock speed is
typically measured in megahertz (MHz).
CMOS. Complementary metal-oxide
semiconductor. A technology that combines the
electrical properties of n-type semiconductors and
p-type semiconductors.
code. A collection of instructions that are in a form
that can be read and processed by a computer.
code page. An assignment of graphic characters
and control function meanings to all code points;
for example, assignment of characters and meanings
to 256 code points for an 8-bit code, assignment of
characters and meanings to 128 code points for a
7-bit code.
compatibility. The capability of a hardware or
software component to conform to the interface
requirements of a given computer without adversely
affecting its functions.
computer architecture. (1) The logical structure
and functional characteristics of a computer,
including the interrelationships among its hardware
and software components. (2) The organizational
structure of a computer system, including hardware
and software.
computer security. (1) Concepts, techniques,
technical measures, and administrative measures
used to protect the hardware, software, and data of
an information processing system from deliberate or
inadvertent unauthorized acquisition, damage,
destruction, disclosure, manipulation, modification,
use, or loss. (2) Protection resulting from the
application of computer security.
configuration. The manner in which the hardware
and software of an information processing system
are organized and interconnected.
configure. To set up a computer for operation by
describing to the system the devices, optional
features, and programs installed in the computer.
connector. An electrical part used to join two or
more other electrical parts.
control. The determination of the time and order in
which the parts of a computer and the devices that
contain those parts perform the input, processing,
storage, and output functions.
controller. A device that coordinates and controls
the operation of one or more input/output devices,
such as workstations, and synchronizes the
operation of such devices with the operation of the
system as a whole.
coprocessor. In personal-computer systems, a
microprocessor that supplements the operations of
the system microprocessor, enabling the computer to
51
perform complex mathematical operations in parallel
with other operations.
cycle. (1) An interval of space or time in which one
set of events or phenomena is completed. (2) A
complete vibration, electric oscillation, or alternation
of current.
D
daisy chain. A method of device interconnection
for determining interrupt priority by connecting the
interrupt sources.
data. (1) A re-interpretable representation of
information in a formalized manner suitable for
communication, interpretation, or processing.
(2) Any representations such as characters or analog
quantities to which meaning is or might be assigned.
data bus. A bus used to communicate data
internally and externally to and from a processing
unit, storage, and peripheral devices.
DDC. Display Data Channel
decibel (dB). A unit that expresses the intensity of
a sound.
decimal. Pertaining to a system of numbers to the
base 10; decimal digits range from 0 through 9.
default. Pertaining to an attribute, condition, value,
or option that is assumed when none is explicitly
specified.
device. A mechanical, electrical, or electronic piece
of equipment designed to serve a special purpose or
perform a special function.
device driver. A file that contains the code needed
to use an attached device.
diagnostic. Pertaining to the detection and isolation
of errors in programs and faults in equipment.
diagnostic program. A computer program that is
designed to detect, locate, and describe faults in
equipment or errors in computer programs.
digital. (1) Pertaining to data in the form of digits.
(2) Contrast with analog.
52
DIMM. Dual inline memory module
direct memory access (DMA). The transfer of data
between memory and input/output devices without
microprocessor intervention.
diskette. A small magnetic disk permanently
enclosed in a rigid or semi-rigid protective jacket.
diskette drive. The mechanism used to seek, read,
and write data on diskettes. It can be installed in, or
attached to, a computer.
disk swapping. A form of memory management
whereby if additional memory is needed for the
active programs, the operating system transfers the
least-used information from memory to the hard
disk to make more memory available. When the
transferred information is needed, it is exchanged
with other information in memory.
Display Data Channel (DDC). An industry
standard for passing monitor configuration
information between a monitor and the attached
personal computer. Plug and Play technology is
used to provide automatic performance optimization
for the monitor. A DDC-enabled computer can
interpret configuration information from a
DDC-enabled monitor and then set the display
mode that best uses the capabilities of the monitor.
Display Power Management Signaling (DPMS). A
monitor feature that makes it possible for the
attached personal computer to safely lower and
manage the power consumption level of the
monitor, based on defined modes of inactivity of the
keyboard and mouse. The power level can be
progressively lowered each time the monitor is
placed into the next mode—from On, to Standby, to
Suspend, to Off. To take advantage of this feature,
the monitor must be used with a computer and
operating system that are hardware and software
enabled for DPMS. If the monitor is attached to a
video adapter, the adapter must also be DPMS
enabled.
DMA. Direct memory access.
DMI. Desktop Management Interface
DPMS. Display Power Management Signaling
DRAM. Dynamic random-access memory.
Dual inline memory module. A small circuit board
with memory-integrated circuits containing signal
and power pins on both sides of the board.
dual processing. A process in which a personal
computer uses the resources of two microprocessors,
instead of one, to share the processing tasks. This
architecture provides the capability of faster
processing speed and faster throughput to
input/output devices. Most operating systems that
support dual processing use symmetric
multiprocessing.
E
EEPROM. Electrically erasable programmable
read-only memory.
electrically erasable programmable read-only
memory (EEPROM). EPROM that can be
reprogrammed while it is in the computer.
EPROM. Erasable programmable read-only
memory.
erasable programmable read-only memory
(EPROM). Programmable read-only memory that
can be erased by a special process and reused;
specifically, a PROM that must be removed from the
computer to be reprogrammed.
expansion bus. An extension of the I/O bus that
has connectors for attaching adapters to the bus.
expansion slot. In personal-computer systems, one
of several receptacles in the rear panel of the system
unit into which a user can install an adapter.
F
file. A named set of records stored or processed as
a unit.
flash memory. A data storage device that is
programmable, erasable, and does not require
continuous power. The chief benefit of flash
memory over other programmable and erasable data
storage devices is that it can be reprogrammed
without being removed from the circuit board.
format. To prepare a hard disk or diskette to hold
information.
frequency. The rate of signal oscillation, expressed
in hertz.
G
GB. Gigabyte.
gigabyte. (1) For processor storage and real and
virtual memory, 230 or 1073741824 bytes. (2) For
disk storage capacity, 1000000 KB. (3) For
transmission rates, 1000000000 bytes.
H
hard disk drive. A disk drive that reads and writes
data on rigid disks and can be installed in or
connected to a computer.
hardware. (1) All or part of the physical
components of an information processing system,
such as computers or peripheral devices. (2) The
equipment, as opposed to the programming, of a
computer. (3) Contrast with software.
hertz (Hz). A unit of frequency equal to one cycle
per second.
hex. See hexadecimal.
hexadecimal. Pertaining to a system of numbers to
the base 16; hexadecimal digits range from 0
through 9 and A through F, where A represents 10
and F represents 15.
I
input/output. Pertaining to a device, process, or
channel involved in data input, data output, or both.
input/output device. A device in a data processing
system by means of which data can be entered into
the system, received from the system, or both.
instruction. A statement that specifies an operation
to be performed by a microprocessor and that
identifies data involved in the operation.
53
instruction set. The set of instructions of a
computer, of a programming language, or of the
programming languages in a programming system.
load. To bring all or part of a computer program
into memory from auxiliary storage so that the
computer can run the program.
interrupt. An instruction that directs the
microprocessor to suspend what it is doing and run
a specified routine. When the routine is complete,
the microprocessor resumes its original work. See
also routine.
local area network (LAN). (1) A computer network
located on a user's premises within a limited
geographical area. Communication within a local
area network is not subject to external regulations;
however, communication across the LAN boundary
may be subject to some form of regulation. (2) A
network in which a set of devices are connected to
one another for communication and that can be
connected to a larger network.
I/O. Input/output.
ISA. Industry Standard Architecture.
ISO. International Organization for
Standardization. An organization of national
standards bodies from various countries established
to promote development of standards to facilitate
international exchange of goods and services, and
develop cooperation in intellectual, scientific,
technological, and economic activity.
logical. (1) Pertaining to content or meaning as
opposed to location or actual implementation.
(2) Pertaining to a view or description of data that
does not depend on the characteristics of the
computer system or the physical storage.
(3) Contrast with physical.
jack. A connecting device to which a wire or wires
of a circuit can be attached and that is arranged for
insertion of a plug.
low-level format. A type of disk formatting that
erases all readable information from a hard disk by
writing zeros on all data sections of the disk to
ensure that no readable information is left on the
disk. Low-level formatting requires a low-level
format program, which is available from a number
of manufacturers.
jumper. A device, such as a short wire, used to
open or close a circuit.
M
J
K
MB. Megabyte.
kilobyte. Approximately 1000 bytes.
megabyte. (1) For processor storage and real and
virtual memory, 220 or 1048576 bytes. (2) For disk
storage capacity, 1000 KB. (3) For transmission
rates, 1000000 bytes.
L
megahertz (MHz). A unit of measure of frequency
equal to 1000000 cycles per second.
LAN. See local area network.
memory. Addressable storage space in the
computer that is used for temporary storage of
instructions and data while a program is running, or
for permanent storage of microcode. Contrast with
auxiliary storage.
KB. Kilobyte.
legacy device. A device that is not Plug and Play
(automatic configuring) compatible. A legacy device
must be manually configured by setting its switches
or jumpers, and then manually assigned computer
resources using the computer configuration/setup
utility program. Contrast with Plug and Play
device.
menu. A list of choices that gives users access to
actions that can be applied to an object.
MHz. Megahertz.
54
microprocessor. An integrated circuit that contains
the central processing unit (CPU) of a computer.
See processor and central processing unit.
MIDI. Musical instrument digital interface
millimeter (mm). One thousandth of a meter.
millisecond (ms). One thousandth of a second.
milliwatt (mw). One thousandth of a watt.
modem (modulator/demodulator). (1) A functional
unit that modulates and demodulates signals. One
of the functions of a modem is to enable digital data
to be transmitted over analog transmission facilities.
(2) A device that converts digital data from a
computer to an analog signal that can be transmitted
on a telecommunication line, and converts the
analog signal received to data for the computer.
multiplexer. A device capable of transmitting
several messages or signals simultaneously on the
same circuit or channel.
multitasking. A mode of operation that provides
for concurrent performance, or interleaved
execution, of two or more tasks.
N
nanosecond (ns). One thousandth of one millionth
(10−9) of a second.
network. (1) An arrangement of nodes and
connecting branches. (2) A configuration of data
processing devices and software connected for
information interchange.
network administrator. The person responsible for
the installation, management, and control of a
network. The network administrator gives
authorization to users for accessing shared
resources, and determines the type of access those
users can have.
network server. See server.
nonvolatile. (1) Pertaining to a storage device
whose contents are not lost when power is cut off.
(2) Contrast with volatile.
ns. nanosecond.
O
operating system. Software that controls the
execution of programs and that may provide
services such as resource allocation, scheduling,
input/output control, and data management.
P
parallel. Pertaining to a process in which all events
occur within the same interval of time, each handled
by a separate but similar functional unit.
parallel port. An access point through which a
computer transmits or receives data that consists of
several bits sent simultaneously on separate wires.
Contrast with serial port.
parity bit. A check bit appended to an array of
binary digits to make the sum of all the binary
digits, including the check bit, always odd or always
even.
password. A string of characters known to the
computer system and to a user, who must specify it
to gain full or limited access to a system and to the
data stored within it.
PC Card. A credit-card-sized adapter used to add
memory, storage, or I/O capabilities to a personal
computer, personal communicator, or other
electronic device.
PCI. Peripheral component interconnect.
pel. (1) Picture element. (2) In computer graphics,
the smallest element of a monitor surface that can be
independently assigned color and intensity.
peripheral device. Any device that can
communicate with a particular computer; for
example, input/output units, auxiliary storage.
physical. (1) Pertaining to actual implementation
or location as opposed to conceptual content or
meaning. (2) Contrast with logical.
55
picture element (pel). In computer graphics, the
smallest element of a monitor surface that can be
independently assigned color and intensity.
program. (1) A sequence of instructions that a
computer can interpret and execute. (2) To design,
write, modify, and test computer programs.
pin. One of the conducting contacts of an electrical
connector.
programmable read-only memory (PROM). A
storage device that, after being written to once,
becomes read-only memory.
pipeline. A serial arrangement of processors or a
serial arrangement of registers within a processor.
Each processor or register performs part of a task
and passes results to the next processor; several
parts of different tasks can be performed at the same
time.
plotter. An output unit that directly produces a
hardcopy record of data on a removable medium, in
the form of a two-dimensional graphic
representation.
Plug and Play device. A device that is
auto-configuring. A Plug and Play device comes
with built-in identification and configuration
specifications that enable the computer BIOS to
automatically configure the device and assign it
computer resources. Contrast with legacy device.
PROM. Programmable read-only memory.
prompt. A visual or audible message sent by a
program to request the user's response.
R
random access memory (RAM). (1) A storage
device in which data can be written and read. (2) A
storage device into which data is written and from
which data is read in a nonsequential manner.
read. To acquire or interpret data from a storage
device, from a data medium, or from another
source.
POST. Power-on self-test.
read-only memory (ROM). Memory in which
stored data cannot be modified by the user except
under special conditions. See also EEPROM,
EPROM, and PROM.
power-on self-test (POST). A series of diagnostic
tests that are run automatically by a device when
the power is turned on.
record. (1) A set of data treated as a unit. (2) A
set of one or more related data items grouped for
processing.
priority. (1) A rank assigned to a task that
determines its precedence in receiving system
resources. (2) The relative significance of one job to
other jobs in competing for allocation of resources.
refresh. (1) To recharge a memory location in
volatile memory with an electric current so that it
retains a state or binary value. (2) In computer
graphics, the process of repeatedly producing a
monitor image on a monitor surface so that the
image remains visible.
port. An access point for data entry or exit.
processing. The performance of logical operations
and calculations on data, including temporary
retention of data in microprocessor storage while the
data is being handled.
processor. A functional unit that interprets and
executes instructions. A processor consists of at
least an instruction control unit and an arithmetic
and logic unit. See microprocessor and central
processing unit.
56
register. (1) An integrated circuit that contains 8,
16, or 32 storage locations, each of which can store 1
bit of binary data. See also binary. (2) An area that
stores binary data while it is being processed by the
computer.
resolution. In computer graphics, a measure of the
sharpness of an image, expressed as the number of
lines and columns on the monitor screen or the
number of pels per unit of area.
resource. Any of the computer-system elements
needed to perform required operations, including
storage, input/output devices, processors, data, and
programs.
riser card. A circuit card that connects to the
system board and provides expansion slots for
adding adapters.
routine. A program, or part of a program, that may
have some general or frequent use.
S
SCSI. Small computer system interface.
seek time. The time required for the access arm of
a direct access storage device to be positioned on the
appropriate track.
serial. Pertaining to the sequential or consecutive
occurrence of two or more related activities in a
single device or channel.
serial port. An access point through which a
computer transmits or receives data, one bit at a
time. Contrast with parallel port.
server. (1) A functional unit that provides shared
services to workstations over a network. (2) In a
network, a data station that provides facilities to
other stations.
slot. (1) A position in a device used for removable
storage media. (2) One of several receptacles in the
rear panel of the system unit into which a user can
install an adapter.
small computer system interface (SCSI). A
standard input/output interface used by personal
computers.
SMM. System management mode.
software. (1) All or part of the programs,
procedures, rules, and associated documentation of
a computer. Software is an intellectual creation that
is independent of the medium on which it is
recorded. (2) Contrast with hardware.
startup sequence. In personal-computer systems,
the order that the computer uses to search the direct
access storage devices for an operating system.
storage. A functional unit into which data can be
placed, in which it can be retained, and from which
it can be retrieved.
subsystem. A secondary or subordinate system,
usually capable of operating independently of a
controlling system, and usually having a single
purpose, such as displaying video or reading from
and writing to hard disks. A subsystem can be
integrated into the system board or on an adapter.
super video graphics array (SVGA). A video
standard that supports high-resolution, 1024 x
768-pel graphic images.
SVGA. Super video graphics array.
symmetric multiprocessing. In personal computers,
a multiprocessing design that enables two or more
microprocessors to run concurrently and work
independently, with each microprocessor capable of
performing any task.
system board. In a system unit, the main circuit
board that supports a variety of basic system
devices, such as a keyboard or a mouse, and
provides other basic system functions.
system management mode. A state controlled by
the microprocessor that reduces the power
consumed by components of the computer.
system programs. In personal-computer systems,
startup routines, such as POST and BIOS code, and
utility programs that are used to configure, test, and
update the computer. See also POST, BIOS, and
utility program.
system unit. In personal-computer systems, the
part of the computer that contains the processor
circuitry, read-only memory (ROM), random access
memory (RAM), and the I/O channel.
57
U
UART (universal asynchronous
receiver/transmitter). An electrical circuit that
converts analog data to digital data and digital data
to analog data; it is used in communications devices.
universal serial bus (USB). A serial interface
standard for telephony and multimedia connections
to personal computers.
universal serial bus port. On personal computers,
a port that uses a single connector for devices that
previously used serial, parallel, keyboard, mouse,
and game ports. The USB port connector uses Plug
and Play technology to determine what device is
connected to the port. A hub device can be used to
convert a single USB connector into multiple
attachment points. Data is transmitted in
asynchronous or isochronous mode.
USB. Universal serial bus
utility program. (1) A computer program in
general support of computer processes; for example,
58
a diagnostic program, a trace program, a sort
program. (2) A program designed to perform an
everyday task such as copying data from one
storage device to another.
V
VGA. Video graphics array.
virtual. Pertaining to a functional unit that appears
to be real, but whose functions are accomplished by
other means.
volatile. (1) Pertaining to a storage device whose
contents are lost when power is cut off.
(2) Contrast with nonvolatile.
W
wait state. A period during which a microprocessor
suspends processing while waiting for a response to
a request for an unavailable source.
write. To make a permanent or transient recording
of data in a storage device or on a data medium.
IBM

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Printed in U.S.A.
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