Structure Of The Can Data Telegram - Lenze 8400 StateLine C Reference Manual

10.6 Structure of the CAN data telegram

[10-2] Basic structure of the CAN telegram
The following subchapters provide a detailed description of the identifier and the user
data. The other signals refer to the transfer characteristics of the CAN telegram whose
description is not included in the scope of this documentation.
10.6.1 Identifier
The principle of the CAN communication is based on a message-oriented data exchange
between a transmitter and many receivers. All nodes can transmit and receive quasi-
simultaneously.
The identifier, also called COB-ID (abbr. for communication object identifier), is used to
control which node is to receive a transmitted message. In addition to the addressing, the
identifier contains information on the priority of the message and the type of user data.
The identifier consists of a basic identifier and the node address of the node to be
addressed:
Identifier (COB-ID) = basic identifier + node address (node ID)
Exception: The identifier for process data/heartbeat/emergency objects as well as network
management and sync telegrams is freely assigned by the user (either manually or
automatically by the network configurator), or is permanently assigned.
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
8400 StateLine C | Reference manual
System bus "CAN on board"
Structure of the CAN data telegram