Vehicle CAN Bus Monitor

About the Vehicle CAN Bus Monitor

Vehicle Network Toolbox™ provides a graphical user interface that monitors CAN bus traffic on selected channels. Using the CAN Bus Monitor you can:

  • View live CAN message data.

  • Configure connection to the CAN bus.

  • View unique messages.

  • Attach a database to view signal information.

  • Save the messages to a log file.

Opening the Vehicle CAN Bus Monitor

To open the Vehicle CAN Bus Monitor, type canTool in the MATLAB® Command Window.

Vehicle CAN Bus Monitor Fields

The CAN bus monitor has the following menus, buttons and table.

File Menu

  • Save Messages — Saves messages to a log file.

  • Clear Messages — Clears messages in the Vehicle CAN Bus Monitor window.

  • Exit CAN Tool — Click to exit the CAN Tool window.

Configure Menu

  • Channel — Displays all available CAN devices and channels on your system. Select the CAN channel to monitor.

  • Bus Speed — Opens the Specified bus speed dialog box. To change the bus speed of the selected channel, type the new value in bits per second in the box.

  • Message Filters — Opens the Set Message Filters dialog box. Select an option in the dialog box to configure hardware filters to block or allow messages.

    • Standard Message ID Filter

      • Allow All — Select to allow all standard ID messages.

      • Block All — Select to block all standard ID messages.

      • Allow only — Select to set up custom filtering of messages. Type the standard message IDs that you want to allow.

    • Extended Message ID Filter

      • Allow All — Select to allow all extended ID messages.

      • Block All — Select to block all extended ID messages.

      • Allow only — Select to set up custom filtering of messages. Type the extended message IDs that you want to allow.

  • Database — Selects the database to attach to the CAN messages on the selected channel.

Run Menu

  • Start — Click to view message activity on the selected channel.

  • Pause — Click to pause the display of message activity on the selected channel.

  • Stop — Click to stop the display of message activity on the selected channel.

View Menu

  • Maximum message count — Opens the Specify maximum message count dialog box. To change the maximum number of messages displayed at a time in the Vehicle CAN Bus Monitor, type the new value in the box.

  • Number Format — Select the number format to display message identifier data. Choose Hexadecimal or Decimal.

  • Show Unique Messages — Select this option to display the most recent instance of each message received on the selected channel. If you select this option, the tool displays a simplified version of the message traffic. In this view, messages do not scroll up, but each message refreshes its data with each timestamp. If you do not select this option, the tool displays all instances of all messages in the order that the selected channel receives them.

Help Menu

  • canTool Help — Select this option to see the online help for Vehicle CAN Bus Monitor.

  • About Vehicle Network Toolbox — Select this option to view the toolbox version and release information.

Buttons

Start

Displays message activity on the selected channel.

Pause

Pauses the display of message activity on the selected channel.

Stop

Stops displaying messages on the selected channel.

Save messages

Click this button to save the current message list on the selected channel to a file.

Clear messages

Click this button to clear messages in the Vehicle CAN Bus Monitor window.

Show unique messages

Select this option to display the most recent instance of each message received on the selected channel. If you select this option, the tool displays a simplified version of the message traffic. In this view, messages do not scroll up, but each message refreshes its data with each timestamp. If you do not select this option the tool displays all instances of all messages in the order that the selected channel receives them.

Docking

Click this button to dock the Vehicle CAN Bus Monitor to the MATLAB desktop. To undock, click this button .

Undocking

Click this button to undock the Vehicle CAN Bus Monitor from the MATLAB desktop. To dock, click this button.

Message Table

Timestamp

Displays the time, relative to the start time, that the device receives the message. The start time begins at 0 when you click Start.

ID

Displays the message ID. This field displays a number in hexadecimal format for the ID and:

  • Displays numbers only for standard IDs.

  • Appends an x for an extended ID.

  • Displays an r for a remote frame.

  • Displays error for messages with error frames.

To change the format to decimal, select View > Number Format > Decimal.

Name

Displays the name of the message, if available.

Length

Displays the length of the message in bytes.

Data

Displays the data in the message in hexadecimal format.

To change the format to decimal, select View > Number Format > Decimal.

If you are using a database, click the + sign to see signal information. The tool displays the signal name and the physical value of the message, as defined in the attached database.

Was this topic helpful?