DBC Manager User Guide

The DBC Manager allows you to create, edit, import, and export CAN database (DBC) files. DBC files define how raw CAN data is decoded into meaningful signals — specifying message IDs, signal positions, scaling factors, and units.

When a DBC file is loaded, automatic signal decoding is available throughout the platform: in dashboard widgets, data exports, and agent configuration.

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DBC Files Overview

The DBC Manager displays all uploaded files in a table:

Column	Description
Name	DBC filename
Size	File size in KB
Actions	Edit, Export, and Delete buttons

Toolbar

• Search bar — Filter files by name
• Import button — Upload an existing .dbc file
• Create button (+) — Create a new DBC file from scratch

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Importing a DBC File

1. Click the import button (download arrow icon) in the toolbar
2. Select a .dbc file from your computer
3. The file is uploaded and appears in the list

Imported files retain all message and signal definitions from the original DBC.

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Creating a New DBC File

1. Click the + button in the toolbar
2. Enter a database name (e.g., vehicle_can)
3. Add one or more CAN messages
4. Configure signals within each message
5. Click Create to save

The file is saved as [name].dbc.

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Editing a DBC File

1. Click the edit button (pencil icon) on any file
2. The file is downloaded, parsed, and opened in the editor
3. Modify messages and signals as needed
4. Click Save to update the file

Note: The database name cannot be changed when editing — it preserves the original filename.

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Message Configuration

Each CAN message has the following properties:

Field	Description
Name	Descriptive identifier (e.g., EngineStatus)
CAN ID	Message identifier in hex (e.g., 0x123)
ID Type	Standard (11-bit) or Extended (29-bit)
Frame Type	Normal, FD, or FD no BRS (see below)
DLC	Data Length Code — number of data bytes

Frame Type

The Frame Type dropdown controls whether a message uses classic CAN or CAN FD framing:

Option	Description
Normal	Classic CAN frame (up to 8 data bytes)
FD	CAN FD frame with Bit Rate Switch (BRS) — allows up to 64 data bytes and a higher data-phase bitrate
FD no BRS	CAN FD frame without BRS — up to 64 data bytes at the nominal bitrate

Frame types are stored in the DBC file using the industry-standard VFrameFormat attribute, ensuring compatibility when sharing files with other CAN tools.

When you change a message to FD or FD no BRS, the DLC field allows values up to 64. Switching back to Normal limits DLC to 8.

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Signal Configuration

Each signal within a message has:

Field	Description
Name	Signal identifier (e.g., EngineRPM)
Start Bit	Bit position where the signal begins (0–63)
Length	Number of bits the signal occupies
Byte Order	Little-endian (Intel) or Big-endian (Motorola)
Value Type	Unsigned, Signed, Float, or Double
Factor	Multiplier for scaling (physical = raw × factor + offset)
Offset	Value added after scaling
Min/Max	Valid range for the physical value
Unit	Engineering unit (e.g., rpm, km/h, °C)

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Understanding Signal Scaling

Signals use a linear scaling formula to convert raw CAN values to physical values:

Physical Value = (Raw Value × Factor) + Offset

Example: A temperature sensor with raw values 0–255:

• Factor: 0.5
• Offset: -40
• Raw value 200 → (200 × 0.5) + (-40) = 60°C

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Byte Order (Endianness)

CAN signals can be stored in two byte orders:

Order	Description
Little-Endian (Intel)	Least significant byte first. Start bit is the LSB position. Most common in automotive ECUs.
Big-Endian (Motorola)	Most significant byte first. Start bit is the MSB position. Used by some legacy systems.

Choose the byte order that matches your ECU specification.

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Exporting a DBC File

Click the export button (upload arrow icon) on any file to download it as a .dbc file. Exported files can be shared with other tools or team members.

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Deleting a DBC File

1. Click the delete button (trash icon) on the file
2. Confirm the deletion in the dialog

Warning: Deleting a DBC file may affect dashboards and agents that reference its signals. Exported data remains unaffected.

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Best Practices

1. Use descriptive names — Name messages and signals clearly (e.g., EngineStatus, VehicleSpeed)
2. Document units — Always specify the engineering unit for each signal
3. Set accurate ranges — Configure min/max values to match the physical reality
4. Export backups — Download copies before making major changes
5. Verify byte order — Match the byte order to your ECU specification
6. Use DBC import — When available in widget or agent editors, import from DBC for accurate configuration

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Related Documentation

• Dashboard Guide — Dashboard overview and data visualization
• Widget Configuration Guide — DBC Reader for importing signals into widgets
• Agents Guide — Importing DBC messages into agents