can-mqtt-bridge

This program listens for messages on a CAN bus interface, decodes them according to a DBC file and forwards them to an MQTT broker. The DBC file must include an MQTT topic in the comment field of each signal.

The program is written for a real-time telemetry system for a racecar, but can surely be used in many other scenarios.

Installation

First you will need to install the following libraries.

• Vector_DBC (Bitbucket)
• paho.mqtt.cpp (GitHub)

Now you can compile the program.

$ g++ can-mqtt-bridge.cpp -o can-mqtt-bridge -lVector_DBC -lpaho-mqttpp3 -lpaho-mqtt3as

Usage

Below are the command line options for this program.

Usage: can-mqtt-bridge [options] <CAN interface>

Options: -d FILE          DBC file to decode CAN frames
         -f FREQUENCY     Maximum frequency to forward to MQTT for each signal
         -v               Verbose mode, prints all decoded values
         -H               MQTT host to publish to
         -U               MQTT username
         -P               MQTT password
         -p               MQTT port
         -h               Display this help message

Example: can-mqtt-bridge -d can.dbc -f 5 -H mqtt.example.com -U admin -P admin -p 1883 can0