JVL MIS17 Series User Manual page 299

11.7 More details of CANopen Theory
Index 6000-9FFF:
The standardised device profile area contains all data objects common to a class of de-
vices that can be read or written via the network. The drives profile uses entries from
6000h to 9FFFh to describe the drive parameters and the drive functionality. Within this
range, up to 8 devices can be described. In such a case, the devices are denominated Mul-
ti Device Modules. Multi Device Modules are composed of up to 8 device profile seg-
ments. Using this feature it is possible to build devices with multiple functionality. The
different device profile entries are shifted with 800h.
A 16-bit index is used to address all entries within the object dictionary. In the case of a
simple variable, this index references the value of the variable directly. In the case of re-
cords and arrays however, the index addresses the whole data structure. To allow indi-
vidual elements of structures of data to be accessed via the network, a sub-index has
been defined. For single object dictionary entries such as Unsigned8, Boolean, Integer32,
the value of the sub-index is always zero. For complex object dictionary entries such as
arrays or records with multiple data fields, the sub-index refers to fields within a data-
structure pointed to by the main index. Index counting starts with one.
The DS-301standard constitutes the application and the communications profile for a
CANopen bus, and is the interface between the devices and the CAN bus. It defines the
standard for common data and parameter exchange between other bus devices, and it
controls and monitors the devices in the network. The table below lists some of the com-
munications profile objects
Data
Transfer
PDO
The access from the CAN network is done through data objects PDO (Process Data Ob-
ject) and SDO (Service Data Object).
11.7.2 Boot up telegram
After the initialization phase, a CANopen slave logs on with a boot up message. The node
address of the slave is contained in this. This allows a CANopen master to know which
slaves are connected to the network. The protocol uses the same identifier as the error
control protocols. See the figure below:
One data byte is transmitted with value 0.
JVL Industri Elektronik A/S - User Manual - Integrated Stepper Motors MIS17x, 23x, 34x, 43x
:
Parameter Special
Transfer functions
SDO
SYNC
EMCY
NMT Master
Indication
TT1085GB
Process Data Objects
Service Data Objects
Synchronisation
Emergency
COB-ID = 700h + Node-ID
0
NMT Slave
Request
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