Reading CAN Data

DBC files

Talha Hanif Butt
2 min readJun 28, 2023

I have written an article on CAN bus here:

Today, I want to talk about DBC files.

The CAN signals are recorded using different data loggers like M-Logger. The signals are stored in different formats like a blf file.

In order to read a blf file, we need a dbc file containing signal definitions which work as a decoder for the data in blf file. We also need a software like CANoe to read blf data using a dbc file.

DBC stands for DataBase Container file. These are text files including information on decoding raw CAN bus signals and also specify which CAN signals are contained within a specific message.

The purpose of creation of this file format was record keeping in CAN network.

Each message is converted into a C structure with signals as its members.

DBC data contains following components:

Simple DBC message

A basic message consists of message id and at least one signal.

Signed Signals

A signed signal can be delivered by providing a negative offset to a transmission.

Fractional Signals

By specifying the range and if necessary, accuracy, a fractional signal can be transmitted.

Enumeration Types

An enumeration type is utilized if the user prefers to view names instead of numbers.

Multiplexed Message

A multiplexed message can convey more than 8 bytes with a single message id.

So, that’s it for now, see you later.

References

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Talha Hanif Butt

PhD Student -- Signal and Systems Engineering, Halmstad University, Volvo Trucks http://pk.linkedin.com/in/talhahanifbutt