GLOSSARY
80
Logicube SuperSonix User’s Manual
CRC
(
C
yclic
R
edundancy
C
hecking)
A method of checking for errors in data transmitted
from one device to another, e.g. from one hard
drive to another. With CRC the sending device
applies a 16- or 32-bit polynomial to a block of data
to be transmitted and then appends the result to the
block. The receiving device applies the same
polynomial to the data block and compares that
result with the original. If the two values agree, then
the data has been transmitted without error. If the
values don’t match, then the sender is notified to
resend the block of data.
CRC ensures detection of 99.998% of all possible
errors.
Defragment
The process of taking noncontiguous fragments of a
data file stored on a hard drive and rearranging
them into one contiguous group, resulting in
reduced data access times and more efficient use
of hard drive space.
Fragmentation occurs naturally over time as files
are created, deleted, and modified. Some operating
systems come with a utility for defragmenting
drives. Third party defragment utilities are also
available.
DMA
(
D
irect
M
emory
A
ccess)
A method of transferring data from one computer
device to another directly through main memory
without passing it through the CPU.
EIDE
(
E
nhanced
I
ntegrated
D
rive
E
lectronics)
A high-speed electronic interface used for
transferring data between a computer and the
computer's hard drive. The theoretical maximum
IDE transfer rate is 16.6 MB/sec depending on the
hard drive speed, the transfer mode and the
operating system.
FAT
(
F
ile
A
llocation
T
able)
A table that an operating system uses to locate data
stored on a hard drive. The FAT system for DOS
4.0 and above, and for older versions of Windows
95 is called FAT16. The FAT table for Windows 95
OSR2 or newer, Windows 98 and Windows ME is
called FAT32. FAT16 allows for a maximum of
