Do not use “laboratory” slang

The correct use of terms avoids confusion and misunderstandings. CiA is committed to improve standards and specifications in this direction.

You find still in many publications the terms CAN 2.0A und CAN 2.0B. They refer to the two CAN data frame formats specified in Classical CAN – a new term introduced in ISO 11898-1:2015. The standardized terms Classical Base Frame Format (CBFF) and Classical Extended Frame Format (CEFF) should be used instead in all new publications including handbooks, datasheets, etc.

The CAN community has also agreed to use the terms ISO CAN FD and non-ISO CAN FD to distinguish the in ISO 11898-1:2015 standardized CAN FD protocol from the not standardized predecessor also known as Bosch CAN FD version 1.0.

Because the CAN physical layer does not know anything about the CAN data link protocols such as Classical CAN and CAN FD, it does not make sense to distinguish between Classical CAN and CAN FD transceiver. You can use both kinds of transceivers. However, transmission rate is limited, when using transceivers supporting just bit rates up to 1 Mbit/s. We should always use the term CAN transceiver with the addition qualified for 1 Mbit/s, 2 Mbit/s, or 5 Mbit/s.

CAN-based higher-layer protocols are specified by different organizations. CiA has developed CANopen and CANopen FD, SAE hosts the J1939 protocols, and ISO has standardized the so-called ISO transport layer (ISO 15765-2) as well as the Isobus (ISO 11783 series). And there are more CAN-based higher-layer protocols. Unfortunately, they use different terms for the protocols of the same OSI layer. CiA proposes to harmonize the terminology. The CAN data link layer protocols should be named frames to be consistent with ISO 11898-1:2015. The network layer protocol entities should be called packets. The application layer protocol should specify messages. In some standards and specifications, the terms are mixed and in worst case they are combined – “frame message”.

There are more terms used in CAN technology, which may confuse newcomers and trainees. In the CAN community, we should improve all our documents to make them easier to read and to avoid misinterpretations and misunderstandings. If you need support to do so, please consider to contact CiA office for further support and information.