Beckhoff EPP3504-0023 Short Manual page 120

Commissioning on EtherCAT Master
Colour Meaning
yellow Input variables from the Slave to the EtherCAT Master, updated in every cycle
red Output variables from the Slave to the EtherCAT Master, updated in every cycle
green Information variables for the EtherCAT Master that are updated acyclically. This means that
it is possible that in any particular cycle they do not represent the latest possible status. It is
therefore useful to read such variables through ADS.
Fig. Basic EtherCAT Slave Diagnosis in the PLC shows an example of an implementation of basic EtherCAT
Slave Diagnosis. A Beckhoff EL3102 (2-channel analogue input terminal) is used here, as it offers both the
communication diagnosis typical of a slave and the functional diagnosis that is specific to a channel.
Structures are created as input variables in the PLC, each corresponding to the process image.
Fig. 43: Basic EtherCAT Slave Diagnosis in the PLC
The following aspects are covered here:
Code Function
A The EtherCAT Master's diagnostic
information
updated acyclically (yellow) or provided
acyclically (green).
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Implementation
Version: 1.2
Application/evaluation
At least the DevState is to be evaluated for
the most recent cycle in the PLC.
The EtherCAT Master's diagnostic
information offers many more possibilities
than are treated in the EtherCAT System
Documentation. A few keywords:
• CoE in the Master for communication
with/through the Slaves
• Functions from TcEtherCAT.lib
EPP3504-0023