Skip to main content

LCN smart home integration, free and open source

LCN integration for Gladys Assistant

LCN building automation (outputs, relays, sensors, scenes) through LCN-PCHK.

View on GitHubAll integrations

This integration connects Gladys to an LCN installation (Local Control Network, building automation sold mostly in Germany, Austria and Switzerland) through LCN-PCHK, the coupler software of LCN that runs on a computer of your network (with its licence) and is wired to the bus by an LCN-PKU or LCN-PCK coupler.

Never tested with a real device nor a real installation: the protocol is ported from pypck, the library of the Home Assistant LCN integration. Unofficial, not affiliated with LCN (ISSENDORFF KG).

What it does​

  • Logs in to PCHK with its user name and password, finds the segment couplers, then every module of the bus (the same scan as pypck), with its serial number, firmware, hardware type and the name set in LCN-PRO.
  • One Gladys device per module. Its features come from the Ports field:
    • outputs A1 to A4 and relays R1 to R8: read only by default (their state, and the level of an output) with "turn on" / "turn off" buttons that are off by default. Declared light (an output: a light with its brightness; a relay: an on/off light) or switch, they can be controlled from Gladys;
    • binary sensors B1 to B8: an input, or a motion sensor (motion);
    • variables TVAR, R1VAR, R2VAR, VAR1 to VAR12: a temperature (°C, by default), humidity (%), lux (light sensor on the I port), co2 (ppm) or a raw value;
    • set points R1VARSETPOINT, R2VARSETPOINT of the regulators: read only, shown as temperatures (never as a thermostat a voice assistant could set). A module not listed in Ports shows A1 and A2, read only.
  • The keys a module sends to the host (programmed with LCN-PRO) become a scene trigger "LCN key sent to the host": module (M5, or S12M5 on segment 12), key table A to C, key 1 to 8, short press (hit), long press (make) or release (break).
  • A scene action "Activate an LCN scene" (register 0-9, scene 0-9, for the outputs, the relays or both), off by default.

Configuration​

FieldWhat to enter
Address of LCN-PCHKThe IP address of the computer running PCHK (give it a fixed address).
Port4114 unless changed in PCHK.
User name, passwordThose of PCHK. The password is a secret field: kept by Gladys in its database, never shown again, sent only to PCHK, never written in the logs. PCHK receives it in clear text on your network: its protocol is not protected, keep PCHK on a trusted network.
Dimming mode200 steps when every module has a firmware from 2013 (170206) or later, as LCN-PRO programs it; else 50 steps.
PortsSee below.
Allow the "turn on" / "turn off" buttonsOff by default.
Allow activating LCN scenesOff by default.

Ports​

Entries separated by commas: module.port or module.port:kind, the module as LCN-PRO numbers it (M5, 5, or S12M5 on segment 12). Example:

M5.A1:light, M5.A2:switch, M5.R3:switch, M5.B1:motion, M7.TVAR, M7.VAR4:humidity, M7.R1VARSETPOINT

Never declare as light or switch a port that drives a pump, a heater, a boiler demand, a door strike, a valve, a freezer or anything a sudden "off" or "on" could harm: a light or a switch obeys Google Home, Alexa, the MCP ("turn everything off") and every scene. Keep such ports read only.

A port that changes kind gets new features; the ones you already created are kept with their history (delete them in Gladys if you no longer want them). A light or a switch kept from before refuses commands once the port is no longer declared as such.

Safety​

  • A command is written within 3.5 s or not at all ("nothing was sent"); it is confirmed only by a status of the port, received after it, equal to the value asked; otherwise Gladys shows "sent, without confirmation" and the port is read again 2 s later.
  • A "turn off" (0 %, relay off) has a queue of its own, written before every other command and every read, without waiting for a quiet bus: a "turn everything off" of 40 lights is written within the deadline. It cancels a "turn on" of the same port, and an LCN scene of the same module, still waiting. The status read after a command goes in the background (one per port, merged); the modules also send their changes by themselves.
  • The options are checked when the command arrives and again right before it is written.
  • A user name or password refused by PCHK stops the connection, and so does a session that PCHK closes right after the password, without an answer, twice in a row: no new try with the same credentials, even after a restart (a salted fingerprint of the refused credentials is kept in /data, never the password; it is erased at the first successful login). Enter other credentials, or click "Test the connection" once fixed on the PCHK side (one try, never closer than 10 s to the last one).
  • A licence error of PCHK (all its connections taken) pauses for 5 min, then 15 min, 30 min, 1 h; the pause survives a restart, and "Test the connection" says how long it still lasts instead of trying.
  • A user name or password holding a line break is never sent (a status says so). An LCN scene goes only to a module of this integration (segment 0 or 5 to 127, module 5 to 254): never to PCHK nor to a broadcast address.
  • Connection attempts are spaced (10 s, 30 s, 1 min, 2 min, then 5 min) and a restart keeps the spacing; a full read of the states happens at most once a minute; "Scan" scans the bus at most once a minute.

Limits​

  • LCN-PCHK only: no LCN-PKE (direct IP coupler) nor USB.
  • No covers (motors), thresholds, LEDs, key locks, regulator locks or access control in this version; set points are read only.
  • The modules that do not answer the scan can be listed in Ports.
  • The bus does not say which ports are wired: list them in Ports.
  • Docker is not used during development: the image was never run in Gladys.

Configuration settings​

These are the settings LCN asks for in its configuration screen in Gladys.

SettingTypeRequiredDescription
Your LCN installationsectionNoFor LCN installations reached through LCN-PCHK (the coupler software of LCN, with its licence) on a computer of your network. The integration logs in to PCHK, looks for the modules on the bus and reads their outputs, relays, binary sensors and variables; the keys a module sends to the host become scene triggers. Outputs and relays are read only unless you declare them as lights or switches in "Ports". One connection of PCHK is used. Never tested with a real installation. Unofficial, not affiliated with LCN.
Address of LCN-PCHKstringYesThe IP address (or name) of the computer running LCN-PCHK; give it a fixed address in your router.
PortnumberNo4114 unless PCHK uses another one.
PCHK user namestringYesThe user name set in LCN-PCHK.
PCHK passwordsecretNoKept by Gladys in its database, never shown again, sent only to PCHK, never written in the logs. PCHK receives it in clear text on your network (its protocol is not protected). A password refused by PCHK (or a session closed right after it, twice in a row) stops the connection: no new try with it.
Dimming modeselectNoAs programmed with LCN-PRO: 200 steps when every module dates from 2013 (firmware 170206) or later, else 50 steps.
PortsstringNoWhat each module shows, e.g. "M5.A1:light, M5.R3:switch, M5.B1:motion, M7.TVAR, M7.VAR4:humidity" (module as in LCN-PRO, S12M5 on segment 12). Outputs A1-A4 and relays R1-R8: read only by default, "light" or "switch" to control them; a light or a switch obeys Google, Alexa, the MCP ("turn everything off") and the scenes: never declare a pump, a heater, a door strike or a valve. Binary sensors B1-B8 ("motion" optional); variables TVAR, R1VAR, R2VAR, VAR1-VAR12 (temperature by default, or humidity, lux, co2, value); set points R1VARSETPOINT, R2VARSETPOINT (read only, shown as temperatures). A module not listed shows A1 and A2, read only.
Commands of the ports not declaredsectionNoA read-only output or relay has "turn on" and "turn off" buttons, and LCN scenes can be activated from a Gladys scene: both switch loads Gladys does not know (a pump, a heater, a door strike...), so both are off by default. Once allowed, every Gladys user and every scene can use them; each command is written in the integration logs.
Allow the "turn on" / "turn off" buttons of the read-only portsbooleanNo
Allow activating LCN scenes from Gladys scenesbooleanNo
Language of the namesselectNoUsed for the names of the devices and features added from now on.

How to install LCN in Gladys​

  1. In Gladys, open Integrations: LCN appears in the catalog, next to the native integrations, with a community badge.
  2. Click Install. Gladys pulls the Docker image (ghcr.io/lm1lc3n7/gladys-lcn:0.1.1), starts it in a sandbox isolated from the core, and generates the integration's interface (devices, discovery and configuration).
  3. Open the Configuration screen of the integration, fill in the settings, and save.
  4. You can also install it directly from its repository URL: https://github.com/LM1LC3N7/gladys-lcn.

LCN requires Gladys >=5.1.0. The catalog inside Gladys refreshes every hour, so a new version becomes available at most one hour after its release.

Not running Gladys yet? It is free and open source: follow the installation guide to get started.

About external integrations​

LCN is an external integration: a community integration packaged as a Docker container and published on GitHub, that Gladys installs in one click and runs in a sandbox isolated from its core. It is published and maintained by LM1LC3N7, not by the Gladys core team.

Subscribe to the Gladys Assistant newsletter

A few emails per month about new releases and project news. Sent by Pierre-Gilles Leymarie, founder of the project. Unsubscribe anytime 🙂
Last updated on