ABB FEPL-02 Ethernet POWERLINK, User Manual

Page: 96 / 142

96 Communication protocol
DS 301 and DS 402 specification
The application layer communication protocol in the FEPL-02
module is based on the CANopen DS 301 communication profile
and DS 402 device profile for drives and motion control. The
protocol specifies the Object Dictionary in the adapter module, as
well as communication objects for exchanging process data and
acyclic messages.
The adapter module implements 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 acyclic data transmission.
•
NMT response services
NMT response services are used for identity and status
signaling both during the start-up and in runtime.
The Object Dictionary is described in Appendix A – CANopen
Object Dictionary .
Process Data Objects
Process Data Objects (PDO) are used for exchanging time-critical
process data between the master and the slave. Tx PDOs are
used to transfer data from the slave to the master and Rx PDOs to
transfer data from the master to the slave.
PDO mapping defines which application objects are transmitted
inside a PDO. These typically include control and status words,
references and actual values, but most dictionary objects and drive
parameters can be mapped for cyclical communication.
The FEPL-02 adapter module has one receive PDO (Rx PDO) and
one transmit PDO (Tx PDO). In each PDO, 0…16 application
objects can be mapped. PDOs are mapped to objects during
configuration (the NMT_CS_PRE-OPERATIONAL_1 and
NMT_CS_PREOPERATIONAL_2 states).
The Tx PDO is mapped by writing to the 0x1A00 object. By default,
there is no parameter mapped to the Tx PDO. Choose which
parameters are exchanged by the Tx PDO.