General Notes - Ethercat Slave Application - Beckhoff EL3783 Documentation

Commissioning
PDO Content
Indicates the content of the PDO. If flag F (fixed content) of the PDO is not set the content can be modified.
Download
If the device is intelligent and has a mailbox, the configuration of the PDO and the PDO assignments can be
downloaded to the device. This is an optional feature that is not supported by all EtherCAT slaves.
PDO Assignment
If this check box is selected, the PDO assignment that is configured in the PDO Assignment list is
downloaded to the device on startup. The required commands to be sent to the device can be viewed in the
Startup [} 93] tab.
PDO Configuration
If this check box is selected, the configuration of the respective PDOs (as shown in the PDO list and the
PDO Content display) is downloaded to the EtherCAT slave.
5.2

General Notes - EtherCAT Slave Application

This summary briefly deals with a number of aspects of EtherCAT Slave operation under TwinCAT. More
detailed information on this may be found in the corresponding sections of, for instance, the EtherCAT
System Documentation.
Diagnosis in real time: WorkingCounter, EtherCAT State and Status
Generally speaking an EtherCAT Slave provides a variety of diagnostic information that can be used by the
controlling task.
This diagnostic information relates to differing levels of communication. It therefore has a variety of sources,
and is also updated at various times.
Any application that relies on I/O data from a fieldbus being correct and up to date must make diagnostic
access to the corresponding underlying layers. EtherCAT and the TwinCAT System Manager offer
comprehensive diagnostic elements of this kind. Those diagnostic elements that are helpful to the controlling
task for diagnosis that is accurate for the current cycle when in operation (not during commissioning) are
discussed below.
Fig. 128: Selection of the diagnostic information of an EtherCAT Slave
EL3783 Version: 1.1 99