CANopen features

The features apply to hardware products only.


The most important feature of a CANopen device is the NMT (Network management) slave functionality. It means that the Object Dictionary with mandatory objects (see CiA 301) and the NMT slave state machine (see CiA 301) have to be implemented in a CANopen device.

Slave vs Master

A CANopen device must implement the NMT slave functionality and may also implement the NMT master functionality (see CiA 302-2). Please note, that a device implementing just the NMT master functionality is not a CANopen device.


In order to be compliant to CANopen, at least one of the error control services (Node guarding or Heartbeat) must be supported by the device.


The feature „Node-ID assignment“ describes the mechanism used for assignment of the node identification number. The assignment may be executed by means of a hardware switch (local interface), software switch, LSS-Services (layer setting services: see CiA 305), LMT-Services (layer management: see CiA 205), Node-ID claiming procedure (see CiA 416-1) or in a proprietary manner.


A CANopen device may support up to 512 RPDOs (receive process data objects) and up to 512 TPDOs (transmit process data objects) in its Object Dictionary. The supported PDO reception and/or transmission mode (event-triggered, time-triggered, requested by a remote frame, cyclic, or acyclic) describes the PDO scheduling. Further PDO features describe whether the PDO linking (change of the PDO’s CAN-ID) is supported and which type of PDO mapping (static: mapping can not be changed, variable: mapping can be changed in pre-operational state, dynamic: mapping can be changed also in operational state) is supported.


A CANopen device may support up to 127 Server SDOs (service data object) and up to 127 Client SDOs in its Object Dictionary. For CANopen conformance the device must support at least one Server SDO. Additionally the Emergency message (see CiA 301) and the Sync counter (CiA 301 V. 4.1 and higher) may be supported.

CiA 30x

The version of the supported CANopen application layer is also named in the feature table. Whether additional frameworks (CiA 30x) are supported is indicated in the field “Frameworks supported”. The field “Device and application profiles supported” indicates, to which device or application profile (more than one may be supported) a certain product complies to.