Micronics M54E2 PCI/EISA - Manual (Page 70)

G-1 M54E2 System Board Manual
Glossary
16550 UART - A high speed chip for
controlling serial ports. Although
unnecessary for a mouse, it is required
for modems that are 14,400 baud or
faster.
486DX - A type of 32-bit CPU with a
built-in math-coprocessor and internal
cache.
486DX2 - A 486DX CPU where the
internal speed of the CPU operates at
twice the external speed.
486DX4 - A 486DX CPU where the
internal speed of the CPU operates at
three times the external speed.
486SX - A 486DX CPU with no math-
coprocessor.
Asynchronous - Operations that do not
require the clocks of communicating
devices to be coordinated. See Synchro-
nous.
Baby AT - A standard system board size
measuring approximately 13.25” x 8.5”.
Bidirectional Parallel Port - A type of
parallel port that can send and receive
information.
BIOS - An Acronym for Basic Input/
Output System. Configures the system
board and provides hardware information
to the operating system.
Bit - A contraction of Binary digit. The
smallest unit of information in a binary
number system. A bit represents a choice
between either zero or one.
Glossary
Boot - To start up the computer and load
the operating system software. See cold
boot and warm boot.
Bus - A group of electronic paths used to
send data between parts of the system.
On a system board, the bus connects the
peripheral cards with the microprocessor
via the expansion slots.
Bus Mastering - The ability of an
peripheral card to control the bus without
requiring intervention of the CPU.
Byte - A group of adjacent bits treated as
a unit. Eight bits are typically considered
one byte. Also called a character.
Cache - A process where information is
copied from the slower memory (DRAM)
to the faster memory (SRAM). Informa-
tion that is likely to be read or edited is
stored in the cache providing significant
performance increases.
Cache Hit - The percentage of request
for data from memory that can be served
from the cache.
Cache Miss - A memory access which
cannot be supplied from cache.
Cold Boot - Starting the computer by
turning on the power or pressing the
RESET button. A cold boot makes the
processor execute all of the diagnostics.
See boot and warm boot.
CPU - An acronym for Central Process-
ing Unit. A CPU performs arithmetic
calculations, makes logical decisions,
and directs the operation of the computer
in conjunction with the operating system.