Balluff BDG F-NH Series, Руководство по настройке

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A SDO transmission will always be acknowledged by the receiver. In case of a failure an "abort message" is send.
The internal delay time of the encoders is 1 millisecond maximum.
PDO Process Data Object
Use: for transmission of process data. The encoders provide up to four PDOs. A PDO uses the full length of the
data area of a CAN frame (8 bytes) for the process data without additional overhead.
PDOs will not be acknowledged and are suitable for time critical applications.
By using the full 8 bytes for data, there is no additional information about transmitted objects. Therefore the PDO
producer and the PDO consumer have to define the PDO-mapping.
PDOS can be sent on different ways:
•
On request: A node sends a RTR frame to ID of the designated PDO and the encoder returns the PDO.
(The CiA strongly recommends not to use RTR frames. Therefore RTR is not supported by Balluff
encoders!)
•
Synchronously: On the reception of a SYNC message the node send its PDOs.
•
Asynchronously: The sending of the PDOs is triggered by an internal event (e.g. the internal event
timer).
5.3.3 Object dictionary
The object dictionary lists all data types, objects and functions of the communication and the device profile. There
are also manufacturer specific objects listed. The objects are addressed by 16-bit indices (lines) and 8-bit sub-
indices (columns).
Table 5.3 shows the structure of the object dictionary:
Index(hex) Object description
0000 reserved
0001 001F static data types
0020 003F complex data types
0040 005F manufacturer specific data types
0060 007F profile specific static data types
0080 009F profile specific complex data types
00A0 0FFF reserved
1000 1FFF communication profile objects
2000 5FFF manufacturer specific objects
6000 9FFF objects from the "Standard device profiles"
A000 AFFF network variables
B000 FFFF reserved / system variables
Table 5.3: Structure of the object dictionary
5.4 Network management ( NMT)
A CANopen network always needs a network management master. The NMT master controls the NMT states of
all connected nodes. A node can be switched into three different states:
•
Pre-Operational
•
Operational
•
Stopped