Datalogic AMT58 Series, Руководство пользователя

Страница: 175 / 435

INSTRUCTION MANUAL
ix
DCP
Discovery Control Protocol - A communications protocol with
PROFINET IO that allows an IO Controller or Supervisor to find
every PROFINET IO device on a subnet.
Determinism
Determinism means that a system responds in a predictable
(deterministic) manner.
Device name
Before an IO device can be addressed by an IO controller, it must
have a device name. In PROFINET, this method was selected
because it is simpler to work with names than with complex IP
addresses.
Encoder Profile
The PROFINET profile for Encoders is intended to define a stan -
dard application interface for encoders. The profile is a supple -
ment to the PROFIdrive profile, so it is mandatory to read the
PROFIdrive profile before implementing the encoder profile.
Function
Functions (FC) are code blocks which can be programmed by the
user. A FC does not have a "memory". Temporary variables as well
as parameters transferred to the function when the latter is called
are saved in a L stack. They are lost following processing of the
FC.
Function block
Function blocks (FB) are code blocks with a "memory" which are
programmed by the user. They have an assigned instance data
block (instance DB) as memory. Parameters transferred to a FB as
well as the static variables are saved in this data block. An FB con -
tains a program which is always executed when the FB is called by
another code block. Function blocks facilitate the programming of
frequently repeated, complex functions.
Frame ID
The two-byte field in the Ethernet frame which defines the type of
PROFINET IO message.
GSD
The properties of a PROFINET device are described in a GSD file
(General Station Description) that contains all the information
required for configuration. In PROFINET IO, the GSD file is in XML
format. The structure of the GSD file conforms to ISO 15734, which
is the world-wide standard for device descriptions.
GSDML
General Station Description Markup Language - The file containing
the XML description of the PROFINET IO device.
IO Controller
Device used to address the connected IO devices. This means that
the IO controller exchanges input and output signals with assigned
field devices. The IO controller is often the controller on which the
automation program runs.
IO Device
A decentralized field device that is assigned to one of the IO con -
trollers (e.g. remote IO, encoders, valve terminals, frequency con -
verters, switches, etc.).
IO Parameter Server
An IO Parameter Server is a server station, usually a PC, for load -
ing and saving the configuration data (records) of IO Devices.
IO Supervisor
Programming device, PC or HMI device used for commissioning
and diagnostics of IO Controllers and IO Devices.
IP address
The IP address is the name of the unit in a network using the Inter -
net protocol.
IRT
Synchronized transmission procedure for the cyclic exchange of
IRT data between PROFINET devices. A reserved bandwidth within
the send clock is available for the IRT IO data. The reserved band -
width ensures that the IRT data can be transmitted at reserved,
synchronized intervals whilst remaining uninfluenced even by
other greater network loads (e.g. TCP/IP communication or addi -
tional real time communication). The "high flexibility" enables sim -
ple planning and expansion of the system. A topological
configuration is not required.