CiA® 457: CANopen interface profile for wireless transmission

When linking a classic CANopen network to a wireless transmission media (WTM) a gateway device is needed. The purpose of such a gateway device is e.g. to link a remote controller to a crane’s embedded CAN, or to bridge two CAN segments by an link “over the air”. A compilation of use cases is summarized in CiA 812; which is available for free download at CiA’s website. To allow a simple setup of the control architectures required for such use cases, CANopen gateways are needed. These gateways moderate between the “CANopen environment” and the communication techniques, used on a wireless transmission medium. CiA 457 specifies such kind of devices. CANopen devices following the CANopen interface profile CiA 457 support either CAN or any wireless transmission media, for the physical layer and the data link layer. On the higher layers, CiA 457 devices use CANopen. Thus, CiA 457 devices allow the implementation of one virtual CANopen network, based on different lower layer, wireless, communication techniques.

Block diagram of a CiA 457 compliant router device; often only two ports are implemented – one CANopen interface and one WTM interface

According to CiA 457, a WTM-based CANopen device supports the CANopen device architecture with the object dictionary. Furthermore, the basic CANopen communication services, such as the SDO server channel, Emergency producer and heartbeat producer are supported. Optionally, SDO client functionality, PDOs, Emergency consumer- or Heartbeat consumer functionality can be supported. Devices moderating between a CAN-based and an WTM-based environment need to support both type of interfaces; CAN-based and WTM-based ones. Such CANopen router devices can basically utilize the functions that have already been specified in CiA 302-7. Just for configuration purposes, additional management functions for the lower layers (LLM) are provided by CiA 457.

For connecting CAN segments “over the air”, CiA 457 devices use communication techniques, specified in CiA 315 - CANopen generic frame for wireless tunneling and for transfer of diagnostic data.

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CiA 457 version 1.1.0CANopen interface profile wireless transmission
DescriptionThis document specifies the CANopen interface profile for devices providing a gateway function to wireless transmission media ports.
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DS728 KiB2022-08-09Login