JVL MAC00-EC41 - Page 120

120 JVL Industri Elektronik A/S - User Manual - Ethernet for MAC and MIS motors
5.2 Protocol specifications
5.2.4 Application layer communication
The application layer communication protocol in Ethernet POWERLINK is based on the
CANopen DS 301 communication profile. The protocol specifies the Object Dictionary
in the adapter module, in addition to communication objects for exchanging cyclic pro
-
cess data and acyclic messages.
The MAC00-ELx module uses the following message types:
- Process Data Object (PDO). The PDO is used for cyclic I/O communication, in other
words, process data.
- Service Data Object (SDO). The SDO is used for much slower acyclic data transmis-
sion.
- NMT response services. Used for identity and status signalling during start-up and
runtime.