CAN dictionary

Explains vocabulary and abbreviations used in CAN technology

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Calibration is a process that adapts a system (e.g. engine) to its enviroment by changing parametres in the ECU software. Employs CCP (CAN Calibration Protocol) or XCP (Extended CAN Calibration Protocol).


Controller Area Network (CAN) is a serial bus system originally developed by Robert Bosch. It is internationally stardardized by ISO 11898-1. CAN has been implemented by many semiconductor manufacturers.

CAN Application Layer (CAL)

Application layer developed by CiA (CAN in Automation) members providing several communication services and corresponding protocols.

CAN common ground

Each CAN network requires a common ground that avoids common mode rejection problems. However, there is a chance that there are unwanted loop currents via ground potential.

CAN device

Hardware module providing at least one CAN interface.


CAN with flexible data rate (CAN FD) enables an increased data throughput. The size of the CAN FD frame's data field may be lengthened to up to 64 byte. In addition, the data phase of the CAN FD data frame may be transmitted with an increased bit rate. The CAN FD protocol is at least as reliable as the Classical CAN protocol.

CAN FD data link layer protocol

The CAN FD data link layer protocol supports Classical CAN frames as well as CAN FD data frames. CAN FD data frames are distinguished by the FDF bit (recessive) from the Classical CAN data frame (dominant).

CAN frame time-stamp

As defined in CiA 603 (in development), a CAN frame time-stamp may be captured at the sample point of the SOF, EOF or on the falling edge from the FOF bit to the res bit. In AUTOSAR, the EOF approach is used.


Indicates the CAN high line in CAN-based networks. The CAN_H line of ISO 11898-2 compliant transceiver is in recessive state at 2,5 V and in dominant state at 3,5 V.

CAN identifier

The CAN identifier is the main part of the arbitration field of a CAN data frame (Classical CAN or CAN FO) or CAN remote frame (only in Classical CAN). It comprises 11 bit (base frame format) or 29 bit (extended frame format) and indicates certain information uniquely in the network. The CAN identifier value determines implicitly the priority for the bus arbitration.

CAN in Automation (CiA)

The international users' and manufacturers' group founded in 1992 promotes CAN and supports CAN-based higher-layer protocols (

CAN Kingdom

Higher-layer protocol framework optimized for embedded networks. It is suitable for real-time applications.


Indicates the CAN low line in CAN-based networks. The CAN_L line of ISO 11898-2 compliant transceiver is in recessive state at 2,5 V and in dominant state at 1,5 V.

CAN message specification (CMS)

Part of the CAN Application Layer (CAL) specification, defining the communication services.

CAN module

Implementation of the CAN protocol controller plus the hardware acceptance filter and the message buffers within a micro-controller or application-specific integrated circuit (ASIC).

CAN node

Synonym for CAN device.

CAN protocol controller

The CAN protocol controller is part of a CAN module performing data en-/de­capsulation, bit timing, CRC, bit stuffing, error handling, failure confinement, etc.

CAN transceiver

The CAN transceiver is connected to the CAN controller and to the bus lines. It provides the line transmitter and the receiver. There are high-speed, fault­ tolerant, and single-wire transceivers available as well as transceivers for power-line or fiber optic transmissions.


Higher-layer protocol for avionic and aerospace applications.


Family of profiles for embedded networking in industrial machinery, medical equipment, building automation (e.g. lift control systems, electronically controlled doors, integrated room control systems), railways, maritime electronics, truck-based superstructures, off-highway and off-road vehicles, etc.

CANopen Lift

Unregistered trademark for the CiA 417 application profile for lift control systems.

CANopen manager

The CANopen manager is responsible for the management of the network. In the CANopen manager device, there resides the NMT (network management) master functionality. Additionally, there may reside the SOO manager (service data object) or/and the configuration manager. A CANopen manager owns a CANopen object dictionary and supports also the CANopen NMT slave functionality.

CANopen master

CANopen device that supports the NMT master FSA in addition to the NMT slave FSA.

CANopen Safety

Communication protocol enhancement allowing transmission of safety-related data. It is standardized in EN 50325-5. The protocol requires just one physical CAN network. Redundancy is achieved by sending each message twice with bit­ wise inverted content using two identifiers differing at least in two bits.

CANopen Safety Chip (CSC)

This 16-bit micro-controller provides a CANopen Safety protocol firmware implementation. It complies with EN 50325-5 and is certified by TOV Rhineland up to SIL 3 (safety integrity level).

CAPL (CAN access programming language)

CAPL is an ANSI C-based programming language extended by network-specific functions and data types. CAPL is used in CANalyzer and CANoe tools from Vector.


See classical base frame format.

CCP (CAN calibration protocol)

CCP is short for CAN Calibration Protocol. CCP describes a protocol for the data communication with ECUs and for the block transfer of memory areas.


See classical extended frame format.


Official compliance test of components or devices to a specific standard. The C&S group performs conformance testing of CAN controller chips. ODVA officially certifies DeviceNet products, and CiA officially certifies CANopen devices.

classical base frame format (CBFF)

In Classical CAN, format for data frames or remote frames using an 11-bit identifier. The data frames are transmitted with one single bit rate and include up to 8 data bytes.

Classical CAN

CAN applications based on ISO 11898-1 which do not support the CAN FD data link layer protocol.

classical extended frame format (CEFF)

In Classical CAN, format for data frames or remote frames using a 29-bit identifier. The data frames are transmitted with one single bit rate and include up to 8 data bytes.

classical frame

Data frame or remote frame using CBFF or CEFF format.


Unregistered trademark for the CiA 422 application profile for municipal vehicles.

client SDO

The client SDO initiates the SDO communication by means of reading or writing to the object dictionary of the SDO server device.

client-server communication

In a client/server communication the client initiates the communication with the server. It is always a point-to-point communication.


See communication object.


In CANopen and CAL, the COB-ID specifies the CAN identifier and additional parameters (valid/invalid bit, remote frame support bit, frame format bit) for the related communication object (COB).

communicating state

A CANopen NMT slave FSA state in which a device owns in principle the ability to communicate. It covers NMT states pre-operational (no PDO transmission allowed), operational (all communication services available) and stopped (only NMT and error control).

communication object (COB)

In CANopen and CANopen FD, a communication object consists of one or more CAN messages with a specific functionality, e.g. PDO, SDO, USDO, EMCY, TIME, or error control.

communication parameter

CAN open device parameter, determining parameter the behavior of the CANopen device at its communication interface.

communication profile

A communication profile defines the content of communication objects such as EMCY, TIME, SYNC, heartbeat, NMT, etc. in CANopen.

configuration manager

The configuration manager provides mechanisms for configuration of CANopen devices during boot-up.

configuration parameter

Parameter in the CANopen object dictionary that configures the application behavior of the device.

confirmed communication

Confirmed communication services require a bi-directional communication, meaning that the receiving node sends a confirmation that the message has been received successfully.

conformance test plan

Definitions of test cases that have to be passed successfully in order to achieve conformance to a communication standard. The conformance test plan for CAN is standardized by ISO 16845.

conformance test tool

A conformance test tool is the implementation of a conformance test plan.


Electro-mechanical component used to make a connection between a device and the CAN bus-line or to extend bus cables. CiA specifies the connector pin-assignment for CAN for CAN and CANopen and ODVA for DeviceNet.


In CAN networks a receiver of messages is called a consumer meaning the acceptance filter is opened.

consumer heartbeat time

Defines in CANopen the time interval required by the monitoring node to verify, whether a monitored node is alive or not. In case, the monitored node transmits no heartbeat message within that time interval, it is regarded as not alive.

contained PDU (G-PDU)

As defined in CiA 602-2, the C-PDU consists of the 3-bit TOC (type of services) field, the service header (5, 13, 21, or 29 bit) and the C-PDU payload (0 to 60 byte).

content-based arbitration

Carrier Sense Multiple Access (CSMA) arbitration procedure where simultaneous access of multiple nodes results in a contention.

control field

In Classical CAN data and remote frames, the 6-bit control field contains the four DLC bits, the IDE bit and the reserved bit(s). In the CAN FD data frame the 9-bit control field is enhanced by the FDF, BRS and ESI bit.


See cyclic redundancy check.

CRC error

Is detected when the calculated CRC sequence does not equal the received one. In FD frames, a mismatch between the counted stuff-bits and the received stuff count shall be treated as a CRC error. The corresponding error frame is transmitted after the acknowledge field.

CRC field

The CRC field contains the CRC sequence followed by a recessive CRC delimiter. In CAN FD frames, the CRC field also contains the stuff count. The 15-bit CRC sequence is used for Classical CAN. The 17-bit and 21-bit CRC sequences are respectively used for CAN FD frames with up to 16-byte or longer than 16-byte data field. The hamming distance is specified as 6. The CRC sequence is able to detect 5 randomly distributed bit failures or a burst failure of up to 15 bit in SOF, arbitration, control, and data fields.


The Carrier Sense Multiple Access / Collision Detection with Arbitration on Message Priority is the bus arbitration method used in CAN. This method arbitrates simultaneous bus access requests.

cyclic redundancy check (CRC)

CRC is performed by a polynomial implemented in transmitting and in receiving CAN modules to detect corruption while transmitting CAN data frames or CAN remote frames (only in Classical CAN).

Source CANdictionary (2016) - CiA CAN in Automation -