Process Data Objects (Pdo); Overview; Pdo Mapping Settings - Omron GRT1-ECT Operation Manual

2 EtherCAT Communication details

2-3 Process Data Objects (PDO)

This section contains information on Process Data Objects (PDOs) and their mapping.

2-3-1 Overview

The Process Data Objects (PDO) are used for real-time data transfer via cyclic communication.
There are two types in PDO: RxPDO that transfers data from the EtherCAT Master to the EtherCAT
Slave and TxPDO that transfers the present value from an EtherCAT Slave to the EtherCAT Master.
EtherCAT
Master
Unit
The EtherCAT application layer can contain multiple objects to configure the process data being
exchanged. The details of process data are described in PDO Mapping Objects and Sync Manager
PDO Assignment Objects.
GRT1-series EtherCAT Communication Unit supports PDO mapping for I/O control.

2-3-2 PDO Mapping Settings

The PDO mapping indicates the mapping for application objects (real-time process data) between the
object dictionary and PDO.
The number of mapped objects is described in sub-index 0 of the mapping table. In this mapping table,
indexes 1600 hex to 17FF hex are used for RxPDO and 1A00 hex to 1BFF hex are used for TxPDO.
2 - 4
RxPDO
output data, operation command, ...
TxPDO
input data, status, ...
EtherCAT
Slave
Unit
GRT1-series EtherCAT Communication Unit - Operation Manual