Configuring CAN and CAN FD Channels

CAN channel functions in MATLAB and CAN configuration blocks in Simulink enable you to define a connection to Vector CAN interface hardware that establishes a physical connection with a CAN bus using either the CAN or CAN FD standard. Vehicle Network Toolbox provides CAN channel functions to query and configure CAN interface hardware settings, such as bus speed and transceiver settings. You can also verify other CAN channel properties, such as the number of messages available and the number of messages received or transmitted on the channel. By attaching Vector CAN database files to CAN channels, incoming messages are automatically presented using information stored in the database. After defining a CAN channel, you can send and receive CAN messages on the channel.

Vehicle Network Toolbox provides functions and blocks for communicating via J1939—a CAN-based high-level protocol commonly used in the heavy-duty truck industry. When communicating over J1939, you use MATLAB functions or Simulink blocks to set up the communication. Specifically, functions and blocks are provided to associate a database (.dbc) file to the J1939 communication, to specify the CAN interface hardware, and to transmit and receive J1939 parameter groups. You encode and decode signal data on the network using parameter groups defined by the database file associated with the connection. Additionally, you can configure Simulink to operate as network nodes with address claiming.

Vehicle Network Toolbox lets you associate a Vector CAN database file with a CAN channel or message from MATLAB or Simulink, enabling you to encode and decode CAN messages using application-specific message and signal names such as EngineMsg and EngineRPM, as well as scaled engineering units. The ability to work with industry-standard database files simplifies the interaction with the CAN bus because the database not only specifies the message list and component signals, but also provides the bit packing and unpacking rules for the associated signals. Signal data type, start bit, length, and byte order are all predefined for the messages in the database, simplifying signal analysis.

With Vehicle Network Toolbox, you can easily import and export measurement data format (MDF) files. The toolbox supports version 3.0 and higher of the MDF standard. When you work with MDF files in MATLAB, you can view the basic properties about the file, including initial time stamp, data size, channel group, and channel name information. You can also create MDF files from MATLAB and write timetable data to existing MDF files.

To read in a subset of an MDF file, you specify the channel names or the start and stop times. By default, the output format of your result will be returned as a timetable so that you can easily work with the time-stamped data.

For large MDF files that don’t fit in memory, you can create an MDF datastore and preview the data in batches based on parameters that you specify. You can also create a datastore to easily work with a collection of similar MDF files.

Access data in ASAM calibration data format (CDFX) with the cdfx function provided by Vehicle Network Toolbox. Use calibration data from a CDF file as inputs to a Simulink model.