Omron NX-ECC201 User Manual

1 EtherCAT Networks
1 - 4
NX-series EtherCAT Coupler Unit User’s Manual (W519)
The following 2 types of communications are available with EtherCAT.
PDO communications are executed in each EtherCAT communications cycle to refresh data continu-
ously. SDO communications are executed between PDO communications.
PDO communications transfers process data cyclically and in realtime.
The EtherCAT master maps the logical process data space to the nodes to achieve cyclic communica-
tions between the EtherCAT master and slaves.
SDO communications is used to perform message communications.
Whenever necessary, the EtherCAT master sends a command to a slave, and then the slave returns a
response to the EtherCAT master.
The following data communications can be performed.
• Reading and writing process data
• Setting slaves
• Monitoring slave status
1-1-2 Types of EtherCAT Communications
Process Data Communications (PDO Communications)
Mailbox Communications (SDO Communications)
EtherCAT master
Slave
Ethernet frame
Slave Slave
Slave
Ethernet
header
Ether
CAT
header
1st EtherCAT
telegram
2nd EtherCAT
telegram
3rd EtherCAT
telegram
CRC
Logical process data
Data a
Data b
Data c

Omron NX-ECC201 Specifications

General

Brand	Omron
Model	NX-ECC201
Category	Controller
Language	English