Specifications

GG
Glossary
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which is a layer of liquid crystal. Behind the sandwich is a reflective layer. In an
unpowered state, light is reflected through the electrodes and liquid crystal to the
reflective layer and back. When current is applied to the liquid crystal, its molecular
structure changes in such a way as to prevent light from passing back from the
reflective layer.
Logical Address: The memory-mapped location of a segment after application of the
address offset to the physical address.
Logical Block Addressing (LBA): A method the system BIOS uses to reference hard
disk data as logical blocks, with each block having a specific location on the disk.
LBA differs from the CHS reference method in that the BIOS requires no information
relating to disk cylinders, heads, or sectors. LBA can be used only on hard disk drives
designed to support it.
 M - N 
Megabyte (MB): One million bytes; 2
20
= 1,048,576 bytes to be exact.
Memory: A designated system area to which data can be stored and from which data
can be retrieved. A typical computer system has more than one memory area. See
Conventional Memory and Extended Memory.
 O 
Offset: The difference in location of memory-mapped data between the physical
address and the logical address.
Operating System: See Disk Operating System.
 P - Q 
Peripheral Connect Interface (PCI): A popular microcomputer bus architecture
standard.
Peripheral Device: An external device connected to the system for the purpose of
transferring data into or out of the system.
Personal Computer/Advanced Technology (PC/AT): A popular computer design
first introduced by IBM in the early 1980s.
Personal Computer Memory AT Attachment (PCM ATA): A popular standard for
interfacing flash memory cards in computer systems.
Personal Computer Memory Card International Association (PCMCIA): The
group of computer hardware designers responsible for development of standards for
use and application of flash memory cards in computer systems.
Personal System 2 (PS/2): Computers designed with IBM’s proprietary bus
architecture known as Micro Channel.
Phase-Locked Loop (PLL): A semiconductor device which functions as an
electronic feedback control system to maintain a closely regulated output frequency
from an unregulated input frequency. The typical PLL consists of an internal phase
comparator or detector, a low pass filter, and a voltage controlled oscillator which