Thread Starter

David Foster

Can anyone explain the differences between CAnbus and Devicenet?

As I understand it, Devicenet is based on Canbus but how are the 2 related?

Peggy Van Walle, ING

I think it is the other way around. Canbus is related to Device Net. canbus is like a "type" of Device net. Example RS 485 is also a kind of
Device Net . With device net for example you can transmit power and data in 1 cable. This cable has a nominal impedance of 120 OHM.
Hope this helps a bit!

James Ingraham

I respectfully disagree. Both CANBus and DeviceNet are based on the RS-485 protocol, which would mean DeviceNet is a "type" of RS-485. So are Profibus and SDS. But the relationship between CANBus and DeviceNet is very close. From the Open DeviceNet Vendors Association
( "": ):

"The Data Link Layer of DeviceNet is completely
defined by the CAN specification and by the
implementation of CAN Controller chips... Several frame types are defined by CAN:
^Õ data frame ^Õ remote frame
^Õ overload frame ^Õ error frame
Data is moved on DeviceNet using the data
frame. The other frames are either not used
on DeviceNet or are for exception handling."

So DeviceNet (and SDS) is a type of CAN. Profibus is not. But all of them are a type of RS-485.

The "About DeviceNet" section of the ODVA website is a good place to look for more info. For a quick reference guide to fieldbuses, check
out Synergetics comparison table at "":

James Ingraham

Sage Automation, Inc.

Linnell, Tim

Canbus is to DeviceNet as RS485 is to Modbus, i.e. one is a physical protocol (i.e. relating to volts and wires) and the other a logical messaging system (i.e. software) overlayed onto the physical layer protocol.

Just to confuse things, canbus is often used as a synonym for CanOpen, which is another messaging system.

Tim Linnell (Eurotherm).
Er, the querent had the right relationship but no details.

Controller Area Networking (CAN) is the media and transceiver system used by many industrial and embedded fieldbuses. CAN specifies only the media and link layer of a communications network.

DeviceNet, SDS, CANopen, and CANKingdom are some of the most common industrial application level protocols that run on CAN networks.

If you want a comparison.... um... DeviceNet is to CAN what TCP/IP is to Ethernet. There, that's a safe one.

Excellent tutorials are available from any of the fieldbus organization sites (ODVA, CiA, etc) and I just read a handy one on


Curt Wuollet

As I understand it DeviceNet is a protocol that uses CANBUS as the transport as do others like CanOpen.