Specifications

GLOSSARY
182 VX 520 REFERENCE GUIDE
Normal Mode The operating mode for normal
transaction processing. The main application
(downloaded and authenticated) starts and displays
an application prompt, indicating that the terminal is
in normal mode. In this mode, the terminal is ready
to process transactions. See Chapter 4, Verix
Terminal Manager.
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
computers or computing devices in which
communication resources are allocated dynamically
on a variety of levels to multiple communicating
entities. Messages 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
download 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
password used to enter terminal manager is called
the Verix Terminal Manager password. In the VX
520 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
outside communication. Typical peripheral devices
for a POS terminal include PIN Pads and check
readers.
Port An opening or connection that provides
electrical 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
verification 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
devices.
Prompt A short message, sent from a process to a
user, indicating that the process expects the user to
input data. For example, a prompt appears on the
terminal display asking the user to enter specific
information. See Messages.
Protocol An agreement that governs the
procedures used to exchange information between
cooperating entities. For example, protocols govern
the format and timing of messages exchanged
between devices in a communication system, such
as between a terminal and a host computer.
PTID Permanent terminal ID. An optional identifier
that can be permanently assigned to a VeriFone
terminal at the factory, upon customer request. The
PTID is an eight digit number, consisting of a two
digit manufacturer’s ID (12 for VeriFone), followed by
a six digit terminal ID. If no PTID is assigned to the
unit then, the default value 12000000 is used.
Pulse dialing A method of telephone dialing that
specifies a phone number by the number of electrical
pulses sent.
RAM Random-access memory. The type of
memory in which storage locations are addressable
and can therefore be accessed in any order. In the
VX 520 terminal, the RAM (or SRAM) is commonly
used to store applications and temporary data
generated during a transaction.
The RAM is battery-backed, meaning that if power is
turned off, data stored in this area of volatile memory
is not lost. Application files and data can also be
stored in the non-volatile flash memory system. By
default, files downloaded to the terminal are stored in
the RAM of the target file group(s). The RAM file
system is called drive I:. See Flash memory.