Issue 01/05  General CANopen definitions 
CANopen Option Module    Operating Instructions 
6SE6400-5BC00-0BP0 
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The COB IDs of the PDOs can be changed by changing the node address or by 
writing into the communication objects. If the COB ID is changed in a 
communications object, then this is only saved in the volatile memory. This means 
that if the MICROMASTER drive unit is isolated from the supply voltage, these 
settings are lost and, after run-up, must be re-set via the bus. If you wish to 
permanently save the change to the COBID, then this must be written via the 
CANopen object 1010H (refer to Section 3.1). 
An object of the object directory is accessed via the SDO channel. However, the 
communication objects (DS301) and the profile-specific objects of the drive profile 
(DSP402) are saved in the object directory of the CANopen option module. In order 
to be able to access additional objects in MICROMASTER, there is an SDO -> 
parameter mechanism. In this case, it does not involve CANopen objects, as the 
numbering of the sub-indices differs with respect to CAN-open (subindex 0 does 
not contain the number of objects, but already the first object). However, the 
objects from the parameter channel can, just like CANopen objects, be read and 
written using SDO access operations - they are designated with a * in the following. 
•  Summary of Data transfer via CANopen 
The messages associated with the CANopen option module can be sub-divided 
into three major areas: 
•  Network management – this means starting and stopping the network as well as 
cyclic node monitoring (using NMT commands) 
•  Process data – this means control words, setpoints, status information and 
actual values (generally use PDO messages) 
•  Object data in order to read/write objects of the object directory or parameter 
values of the drive converter/drive inverter (using SDO messages)