Terminology
Term
Abbre-
viation
Description
CPU Rack --- A Rack to which a CPU Unit or Communication Control Unit is mount-
ed. For NX-series CPU Units to which NX Units can be connected, a
CPU Rack has a CPU Unit with NX Units and an End Cover mounted
to it. For NX-series Communication Control Units, a CPU Rack has a
Communication Control Unit with NX Units and an End Cover mounted
to it.
DC time --- In a CPU Rack of a NX-series CPU Unit to which NX Units can be con-
nected, time indicated by the clock shared between the CPU Unit and
the NX Units. EtherCA
T slaves that support distributed clock synchroni-
zation have a clock that is shared by all slaves in the network.The time
that is based on this distributed clock is called the DC time. The same
clock is shared by a CPU Unit, NX Units connected to the CPU Unit,
and applicable EtherCA
T slaves.
EtherCAT slave information ESI An XML file that contains setting information for an EtherCAT slave.
Refer to 1-2-2 System Configuration of Slave Terminals on page
1-5
for details.
I/O port --- A logical interface that is used by the NJ/NX-series CPU Unit or NY-
series Industrial PC to exchange data with an external device (slave or
Unit).
I/O refreshing --- Cyclic data exchange with external devices that is performed with pre-
determined memory addresses.
NX bus --- The NX-series internal bus.
NX message communications --- Message communications to access NX objects.
PDO communications --- An acronym for process data communications.
SDO communications --- One type of EtherCAT communications in which service data objects
(SDOs) are used to transmit information whenever required.
Refer to the user's manual for the built-in EtherCA
T port on the con-
nected CPU Unit or Industrial PC for details.
Sync0 ---
A signal that gives the interrupt timing based on the distributed clock
(DC) in EtherCAT communications. The slaves execute controls ac-
cording to this interrupt timing.
Refer to the
NX-series EtherCAT Coupler Unit User’s Manual (Cat. No.
W519) for details.
index --- Address of an object within an application process.
object --- An abstract representation of a particular component within a device,
which consists of data, parameters, and methods.
subindex --- Sub-address of an object within the object dictionary.
Slave Terminal --- A building-block remote I/O terminal, which consists of a Communica-
tion Coupler Unit connected with NX Units.
Safety Network Controller --- A building-block Safety Controller, which consists of a Communication
Control Unit connected with Safety Control Units.
task period --- The interval at which the primary periodic task or a periodic task is exe-
cuted.
Refer to the software user
’
s manual for the connected CPU Unit or In-
dustrial PC for details.
Communications Coupler Units --- The generic name of an interface unit for remote I/O communications
on a network between NX Units and a host network master.
Terminology
36
NX-series System Units User's Manual (W523)