CN3 and CN4 are communication ports for EtherCAT protocol. LAN cable from master device will be connected to CN3 (IN) and CN4 (OUT) will be connected to the next slave device.
Example of EtherCAT communication cable connections between master and slave devices
XML File: :nl7_servo:nl7_xml_file.zip
4 Receive PDOs and 1 Transmitt PDO are available as standard configuration.