Concepts

A short vocabulary. The other pages use these words.

Finding your way

The bar at the top has what a setup is made of: Miniservers, Plugins and Wires. The menu under your user name, at the top right, has the pages used now and then: the Bus Inspector, History (what is recorded), Backup, System (what Nexus uses, see System diagnostics), the Docs, Change password and Log out. While one of those pages is open, the menu button shows its name.

Signals and topics

Values have one of these types: null, boolean, number, string, singleChannel, rgbw, tunableWhite and t5 (see Values). Topics look like this:

loxone/haus/in/licht-kueche                       values from the Miniserver "haus"
loxone/haus/out/pv-leistung                       values to the Miniserver
loxone/haus/discovered/abc123                     unknown packet ids that arrived
homeassistant/zuhause/sensor/kitchen-temp         a sensor of the plugin instance "zuhause"
homeassistant/zuhause/actuator/kitchen-light      a command to a device
system/plugin/zuhause/status                      health of a plugin instance
system/loxone/haus/status                         health of a Miniserver

The parts come from slugs (lowercase letters, digits, ., _, -) that you choose. Renaming something changes its topics; wires and signals refer to internal IDs, so they keep working.

Wires and transforms

A wire carries values from a source signal to a target signal. Transforms change the value on the way. Each target can be fed by one wire. See Wires.

Forces

A force pins a topic to a value. While a topic is forced, every subscriber sees the forced value; real values keep arriving and are recorded as shadowed, so you see what would have happened. Forcing a Miniserver out topic sends the forced value to the Miniserver. Forcing an in topic means everything wired to it sees the forced value. A force can expire at a time you choose, and survives restarts. Use it to test a wiring or to hold a value during maintenance.

The Bus Inspector

The Bus Inspector shows every message live, with filters by topic and source. Click a message to see its cause: the command from a wire, the plugin work it triggered and the result with its duration. You can force, release and inject a value from there.

The Miniserver and ICI

Nexus speaks Loxone's Network Intercommunication (ICI), a UDP protocol. Nexus appears to the Miniserver as another Miniserver with its own ID. Each value has a packet ID and a data type. See Setting up a Miniserver.

Plugins, instances, sensors and actuators

A plugin is code; an instance is that code configured once (for example one Home Assistant server). Each instance runs in its own worker thread, so one that crashes or hangs is restarted without affecting anything else. An instance is stopped, starting, running, degraded (it runs but reports a problem), error (it refused to start, for example with wrong credentials; not restarted automatically) or crashed (restarted with a growing delay, 1 s up to 5 min).

Inside an instance you add sensors (values from the device, the source of wires) and actuators (commands to the device, the target of wires). The catalog, if the plugin offers one, lists what the device has, so you add them without typing entity names; search it, and show only sensors or only actuators when it has both. The panel shows the plugin's own status.

Secret settings such as tokens are never sent back to the browser, and an update that leaves them out keeps the stored value.

Plugins are trusted code, not sandboxed. Only install plugins you trust. See Publishing a plugin.