User's Manual Part 4

GLOSSARY
146 OMNI 3600 REFERENCE MANUAL
Memory A device or medium that can retain infor-
mation for subsequent retrieval. The term is most
frequently used to refer to the internal storage of a
computer (or a terminal) that can be directly ad-
dressed by operating instructions. In the Omni 3600,
files can be stored in battery-backed RAM or in non-
volatile flash memory.
Messages Words and symbols appearing on the
display screen which inform the user of the terminal
of the result of a process, or if an error has occurred.
The term “prompt” is used when the displayed mes-
sage is requesting the user to enter information or to
select an option.
Modem Modulator/demodulator. A device that con-
verts a digital bit stream into an analog signal to
transmit over an analog communication channel
(modulation), and converts incoming analog signals
back into digital signals (demodulation). The internal
modem in the Omni 3600 base station lets the termi-
nal communicate with a host computer over a dial-up
telephone line.
Non-volatile memory A memory or storage medi-
um that retains data in the absence of power so that
the data is available when power is restored. For the
Omni 3600, application files and data files can be
stored in battery-backed RAM or non-volatile flash
memory, according to the requirements of the appli-
cation.
Normal Mode The operating mode for normal
transaction processing. The main application (down-
loaded and authenticated) starts and displays an ap-
plication prompt, indicating that the terminal is in
normal mode. In this mode, the terminal is ready to
process transactions. See also System Mode.
Packet A group of bits of fixed maximum size and
well-defined format that is switched and transmitted
as a composite whole through a packet switching
network. Any message that exceeds the maximum
size is partitioned and carried as several packets.
Packet-switched networks Networks of com-
puters or computing devices in which communica-
tion resources are allocated dynamically on a variety
of levels to multiple communicating entities. Messag-
es between entities are partitioned into segments, or
packets, with a fixed maximum size.
Parameter A variable that is usually assigned a
constant value for a specific subroutine, procedure,
or function. Parameters stored in terminal memory or
in the CONFIG.SYS file(s), enable a host or down-
load computer to identify to terminal configuration.
Password A group of characters that identify a
user to the system so that they can gain access to
the system or part of that system. Passwords are
used to ensure the security of computer systems by
regulating the amount of access freedom. The pass-
word used to enter system mode is called the system
mode password. In the Omni 3600 file system, each
file group (Groups 1–15) also has its own password.
PC Abbreviation for personal computer. Usually, PC
refers to an IBM-compatible personal computer.
Peripheral device In a computer system, any
equipment that provides the processing unit with out-
side communication. Typical peripheral devices for a
POS terminal include PIN pads, bar code wands,
and check readers.
Port An opening or connection that provides electri-
cal or physical access to a system or circuit. Also, a
connection point with associated control circuitry that
allows I/O devices to be connected to the internal
bus of a microprocessor.
POS terminal A terminal used at the point of sale,
which is usually at a merchant site where a customer
pays for goods or services received. Information
concerning the sale can be entered into the terminal
and transmitted to a remote host computer for verifi-
cation and processing.
Power pack A unit for transforming and converting
electrical power from one AC voltage level to another
AC voltage level, or from AC to DC, for electronic de-
vices.
Prompt A short message, sent from a process to a
user, indicating that the process expects the user to
present fresh data. For example, a prompt appears
on the terminal display asking the user to enter spe-
cific information. See Messages.
Protocol An agreement that governs the proce-
dures used to exchange information between coop-
erating entities. For example, protocols govern the
format and timing of messages exchanged between
devices in a communication system, such as be-
tween a terminal and a host computer.