asyncio-vedirect-mqtt

This is a simple program for publishing serial data from the Victron VE.Direct protocol to an mqtt broker in an asynchronous manner.

The data is published according to the Home Assistant MQTT Discovery specification. This allows the device to be auto-discovered in home assistant.

Currently, the program is set up for use with SmartSolar devices. Adding more devices is possible (pull requests accepted).

This is done using changyuheng/aioserial to read the serial data and passing it through to an async implementation of karioja/vedirect to decode the data. This is then sent over MQTT to a broker of your choice via sbtinstruments/asyncio-mqtt.

The implementation supports TLS and authentication when connecting to the MQTT server.

Getting started:

Install the latest wheel package from the releases tab or download from git with pip.

pip3 install git+https://github.com/metrafonic/asyncio-vedirect-mqtt.git

NOTE: Installing the pre-built wheel (as opposed to git install via pip) is recommended as it saves a significant amount of space.

This will add the ve-mqtt executable to ~/.local/bin.

Run the code:

$ ve-mqtt -h
Welcome to asyncio_vedirect_mqtt v1.1.3
usage: ve-mqtt [-h] --tty TTY [--windowing WINDOWING] --device DEVICE [-v] [--timeout TIMEOUT] --broker BROKER [--port PORT] [--username USERNAME] [--password PASSWORD] [--mqttretry MQTTRETRY] [--tls] [--tls1.2] [--ca_path CA_PATH]

Async implementation of ve.direct to mqtt

optional arguments:
  -h, --help            show this help message and exit
  --tty TTY             Serial port with incoming ve.direct data
  --windowing WINDOWING
                        How many values should be included in the sliding moving average
  --device DEVICE       Unique name of the device
  -v, --verbose         Run with verbose logging
  --timeout TIMEOUT     Serial port read timeout
  --broker BROKER       MQTT broker hostname
  --port PORT           MQTT broker port
  --username USERNAME   MQTT broker username
  --password PASSWORD   MQTT broker password
  --mqttretry MQTTRETRY
                        MQTT broker reconnect timeout interval
  --tls                 Use TLS for MQTT communication
  --tls1.2              Use TLS version 1.2 for MQTT communication
  --ca_path CA_PATH     Custom TLS CA path

System service

Add the following to /lib/systemd/system/ve-mqtt.service:

[Unit]
Description=VE.Direct over MQTT
After=multi-user.target

[Service]
User=pi
Group=pi
Type=simple
ExecStart=ve-mqtt --device Mobile-1 --tty /dev/ttyAMA0 --broker xxxxx --port 8883 --username mqtt --password xxxxxxxxxx --tls
Restart=on-failure
RestartSec=5s

[Install]
WantedBy=multi-user.target

Remember to replace the arguments with your own variables.

Also replace the username and group in the [Service] section to the user that installed and is capable of running the ve-direct software

Reload and start the service:

sudo systemctl daemon-reload
sudo systemctl enable ve-mqtt
sudo systemctl start ve-mqtt

Development:

Sending test data is easy using socat:

socat -d -d PTY,raw,echo=0,link=/tmp/vmodem0 PTY,raw,echo=0,link=/tmp/vmodem1

cat tests/smartsolar_1.39.dump > /tmp/vmodem0

Data will now be available at /tmp/vmodem1

Credits

• changyuheng/aioserial - async serial implementation
• karioja/vedirect - decoding of ve.direct and the example test file
• sbtinstruments/asyncio-mqtt async mqtt implementation