DoMiQTT - node.js based LCN/Domiq Base-MQTT-bridge

TL;DR

Connects to a Domiq Base (LCN) and translate from and to MQTT.

What does it?

The DOMIQ base (https://domiq.eu/products/d_bl_1b) is a DIN rail mounted device which connects to LCN (http://lcn.de/) building automation. Beside of a Abode flash based webinterface it provides a proprietary and text based event stream on TCP port 4224. Using this port one can read (almost) all LCN events and also trigger actions.

MQTT (http://mqtt.org/) is a very lightweight protocol for e.g. sensor data. Many home automation systems (like OpenHAB http://www.openhab.org/ or Home Assistant https://home-assistant.io/) can talk to MQTT.

This software connects the Domiq's port 4244 on one side and implements a MQTT client to connect to a MQTT broker (e.g. mosquitto https://mosquitto.org) on the other. Thus it's acting a a bridge and enables software like OpenHAB or Home-Assistant to read from and control LCN based smart homes.

Requirements

• Domiq base
• a MQTT broker (e.g. mosquitto)
• node.js/npm

Installation

git clone https://github.com/etobi/domiqtt.git 
cd domiqtt
npm install
cp defaultConfig.json config.json
# edit config.json and adjust the IP of the domiq and MQTT
npm start

Using

Domiq's LCN "channel" adresses look like this

LCN.output.0.20.1

• "LCN" - control something with LCN; Domiq also support other systems like SATEL and provides some internal Values ("VAR." / "MEM."), too.
• "output" - adress a output (e.g. for a light) of given LCN module
• "0" - segment address
• "20" - module address
• "1" - which output of this module.
• check Domiq's manual for details

The DoMiQTT will translate these into MQTT topics like

mqttjs_12345678/james/lcn/LCN/output/0/20/1

• "mqttjs_12345678" - SenderID
• "james/lcn" - a custom prefix configuraable in config.js
• "LCN/output/0/20/1" - LCN channel address separated with / ínstead of .

Ideas

• send MQTT birth/will messages
• more readable LCN/Domiq-address / MQTT-topic mapping
  • mqttjs_12345678/james/lcn/livingroom/light/ceiling instead of mqttjs_12345678/james/lcn/LCN/output/0/20/1
• trigger to read a current LCN value on demand (instead of waiting it to change) (sending "LCN.output.0.20.1=?" to Domiq)
• regulary check all values (sending "?" to domiq) to make sure we dont miss something
• cache LCN values
• calculate ages of changed values
• provide linux init script
• check using MQTT username/password
• more.