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Appendicies
G5 Series AC Servo Drives With Built-in EtherCAT Communications, Linear Motor Type
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EtherCAT Terminology
Use the following list of EtherCAT terms for reference.
Term
Abbreviati
on
Description
Object
Abstract representation of a component within a device, which
consists of data, parameters, and methods.
Object Dictionary
OD
Data structure addressed by Index and Subindex that contains
description of data type objects, communication objects and
application objects.
Service Data Object
SDO
CoE asynchronous mailbox communications where all objects
in the object dictionary can be read and written.
Index
Address of an object within an application process.
Subindex
Sub-address of an object within the object dictionary.
Process Data
Collection of application objects designated to be transferred
cyclically or acyclically for the purpose of measurement and
control.
Process Data Object
PDO
Structure described by mapping parameters containing one or
several process data entities.
Receive PDO
RxPDO
A process data object received by an EtherCAT slave.
Transmit PDO
TxPDO
A process data object sent from an EtherCAT
slave.
Sync Manager
SM
Collection of control elements to coordinate access to
concurrently used objects.
Distributed Clock
DC
Method to synchronize slaves and maintain a global time
base.
Device Profile
Collection of device dependent information and functionality
providing consistency between similar devices of the same
device type.
Fieldbus Memory Management Unit
FMMU
Single element of the fieldbus memory management unit: one
correspondence between a coherent logical address space
and a coherent physical memory location.
Physical Device Internal Interface
PDI
A series of elements to access data link services from the
application layer.
CAN in Automation
CiA
CiA is the international users’ and manufacturers’ group that
develops and supports higher-layer protocols.
CAN application protocol over
EtherCAT
CoE
A CAN application protocol service implemented on EtherCAT.
EEPROM
EEPROM
Electrically erasable PROM.
EtherCAT Technology Group
ETG
The ETG is a global organization in which OEM, End Users
and Technology Providers join forces to support and promote
the further technology development.
EtherCAT Slave Controller
ESC
A controller for EtherCAT slave communication.
EtherCAT State Machine
ESM
An EtherCAT communication state machine.
EtherCAT Slave Information
ESI
An XML file that contains setting information for an EtherCAT
slave.
Slave Information Interface
SII
Slave information stored in the nonvolatile memory of each
slave.
Power Drive System
PDS
A power drive system consisting of a Servo Drive, an inverter,
and other components.