DIALOG: record raw CAN frames or DBC signals with a REBEL

Set a REBEL to record every frame on a CAN bus, or only the signals you choose from a DBC file. Then send the configuration to the logger.

Before you start

• DIALOG Configurator or above.
• The REBEL USB driver.
• The logger, connected over USB.
• The network's bit rate. If you are not sure, see CAN bus baud rate and its calculation.
• The network's DBC file, if you record signals. For what it holds, see Understanding CAN DBC.

Choose your approach. A raw trace records every frame, so nothing is missed and you can decode it later with a DBC file. Recording from a DBC file stores only the signals you choose, so files stay small and already carry engineering values.

Record every CAN frame

1. Create the configuration. Add a configuration and set its sleep mode, a CAN bus such as CAN 0 (HS) and the bit rate. For the steps, see DIALOG: create projects and configurations and send them to a REBEL.
2. Add CAN Monitor. Select New Protocol, choose CAN Monitor and select OK.
3. Log every frame. In New CAN Monitor Protocol, tick Log All Channels for the full CAN trace and select OK.

   

4. Send the configuration to the logger. See DIALOG: create projects and configurations and send them to a REBEL.

The same window also holds the protocol name, Log CAN Errors, Log CAN signals at Slow Rate and Oversample Rate.

Watch: Configuring a REBEL to record raw CAN messages (3:02, recorded with an earlier version)

Record signals from a DBC file

1. Create the configuration. Add a configuration and set its sleep mode, CAN bus and bit rate, as above.
2. Add CAN Monitor. Select New Protocol, choose CAN Monitor and select OK. Do not tick Log All Channels with a DBC file. It is optional.
3. Open the DBC tab. Select the DBC tab on the right edge of the window, then select Load DBC File.

   

4. Load the file. Select your .dbc file, then select Open. The panel lists every signal in it.
5. Find the signals. Narrow the list with Signal Label, Transmitting Node, Ident (Hex) or Units. Use * as a wildcard. For a J1939 file, tick Apply J1939 Filters.
6. Copy the signals. Select them, then select Copy Items. They join the protocol's item list with their label, units, identifier, message name, start bit and bit count.

   

7. Send the configuration to the logger. See DIALOG: create projects and configurations and send them to a REBEL.

To change a DBC file inside DIALOG, select Presets > Show DBC Editor.

Watch: Configuring a REBEL with a DBC file (3:44, recorded with an earlier version)

Check the recording

The REBEL writes its recordings to the SD card as IVD files. DIALOG exports a raw trace as CAN frames, or decodes it with a DBC file into physical values first.

• Use the live data viewer (DIALOG Standard and Plus) to watch values while the logger records. To copy and export the recordings, see DIALOG: view live data, copy recordings and export them.
• To decode many raw recordings with one DBC file at once, use DIALOG Plus batch processing. See DIALOG Plus: batch processing, merging and conversion scripts.
• If nothing is recorded, check the bit rate, the wiring and the termination. Then work through the CAN bus troubleshooting guide and REBEL and DIALOG: frequently asked questions.

Next: DIALOG: record GNSS, analogue and digital inputs.