Concepts and Terminology

Term	Definition
CoE	The CANOpen over EtherCAT communication protocol.
E-CAT API	wRTOS provides several E-CAT APIs for process data exchange. For editing PDO entries, see E-CAT API mode. For APIs to read/write custom PDOs, see Possible APIs used to read/write custom PDOs.
ESI file	An EtherCAT SubDevice Information (ESI) file is an XML-based device description file provided for each EtherCAT SubDevice. It contains detailed information about the SubDevice's specifications, features, and configuration, enabling a MainDevice system to communicate with and operate the SubDevice effectively.
DS402	A communication profile standard developed by CAN in Automation (CiA).
PDO	Process Data Object. Every process data object contains a group of data items (PDO entries) and can be selected to participate in the process data exchange. Some devices will make certain PDOs fixed (the data items in them can't be changed), or mandatory (must participate in process data exchange).
PDO assignment	Select PDOs for process data exchange.
PDO configuration	Configure the data items (PDO entries) in PDOs.
PDO entries	The data items (variables) in PDOs.
Process data exchange	Exchange process data between the EtherCAT MainDevice (the E-CAT Component) and EtherCAT SubDevices (drives or I/Os) every EtherCAT communication cycle (usually 1 millisecond per cycle), including sending input data from the SubDevices to the MainDevice and sending output data from the MainDevice to the SubDevices.
SDO	Service Data Object. SDOs allow the EtherCAT MainDevice to read and write configuration parameters and other detailed information stored in the SubDevices. Unlike real-time data exchange, SDOs are primarily used for setup, diagnostics, and on-demand data exchange.
Device	A Device can be either a Drive or an IO. EtherCAT devices are directly connected to the EtherCAT network.
Module	Hardware devices not directly connected to the EtherCAT network, such as gateways, are considered modules.

CoE

The CANOpen over EtherCAT communication protocol.

E-CAT API

wRTOS provides several E-CAT APIs for process data exchange.

For editing PDO entries, see E-CAT API mode.
For APIs to read/write custom PDOs, see Possible APIs used to read/write custom PDOs.

ESI file

An EtherCAT SubDevice Information (ESI) file is an XML-based device description file provided for each EtherCAT SubDevice. It contains detailed information about the SubDevice's specifications, features, and configuration, enabling a MainDevice system to communicate with and operate the SubDevice effectively.

DS402

A communication profile standard developed by CAN in Automation (CiA).

PDO

Process Data Object. Every process data object contains a group of data items (PDO entries) and can be selected to participate in the process data exchange. Some devices will make certain PDOs fixed (the data items in them can't be changed), or mandatory (must participate in process data exchange).

PDO assignment

Select PDOs for process data exchange.

PDO configuration

Configure the data items (PDO entries) in PDOs.

PDO entries

The data items (variables) in PDOs.

Process data exchange

Exchange process data between the EtherCAT MainDevice (the E-CAT Component) and EtherCAT SubDevices (drives or I/Os) every EtherCAT communication cycle (usually 1 millisecond per cycle), including sending input data from the SubDevices to the MainDevice and sending output data from the MainDevice to the SubDevices.

SDO

Service Data Object. SDOs allow the EtherCAT MainDevice to read and write configuration parameters and other detailed information stored in the SubDevices. Unlike real-time data exchange, SDOs are primarily used for setup, diagnostics, and on-demand data exchange.

Device

A Device can be either a Drive or an IO. EtherCAT devices are directly connected to the EtherCAT network.

Module

Hardware devices not directly connected to the EtherCAT network, such as gateways, are considered modules.

E-CAT ESI Import Tool Concepts and Terminology