MQTT and Home Assistant

Configuration

Configure the broker in the SETTINGS tab of the web interface (MQTT section):

Field	Default	Description
Broker	—	IP or hostname of the MQTT broker
Port	1883	TCP port
Username / Password	—	Optional credentials
Client ID	semaphore	MQTT client identifier
Topic prefix	semaphore	Prefix for all topics

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Auto-Discovery (Home Assistant)

On connection, the device publishes Home Assistant MQTT discovery topics automatically. No manual configuration needed.

Lights

One light entity per LED with RGB color and brightness control:

Entity	Topic
Bottom LED	semaphore/cmd/led/0
Middle LED	semaphore/cmd/led/1
Top LED	semaphore/cmd/led/2

Commands use the HA JSON light schema (state, color, brightness).

Switches

Entity	Description
Cycle	Enable / disable cycle effect
Party mode	Enable / disable party effect
Rainbow	Enable / disable rainbow effect

Buttons

Entity	Description
Random Yes/No	Trigger the yes/no animation
Weather Color	Activate the weather color effect
Air Quality Color	Activate the air quality color effect

Sensors

Entity	Unit	Device class	Update interval
Temperature	°C	temperature	Every 30 minutes (weather fetch)
Humidity	%	humidity	Every 30 minutes (weather fetch)
Condition	text	—	Every 30 minutes (weather fetch)
PM2.5	µg/m³	—	Every 30 minutes (air quality fetch)
PM10	µg/m³	—	Every 30 minutes (air quality fetch)
NO₂	µg/m³	—	Every 30 minutes (air quality fetch)
RSSI	dBm	signal_strength	Every 60 seconds

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Topics

Topic	Direction	Description
{prefix}/cmd	Subscribe	JSON command (same format as WebSocket)
{prefix}/status	Publish	Full device status broadcast
{prefix}/status/led/{n}	Publish	Individual LED state (retained)
{prefix}/status/switch/{name}	Publish	Switch state ON/OFF (retained)
{prefix}/status/weather/temperature	Publish	Temperature in °C (retained)
{prefix}/status/weather/humidity	Publish	Humidity in % (retained)
{prefix}/status/weather/condition	Publish	Condition string (retained)
{prefix}/status/airquality/pm2_5	Publish	PM2.5 in µg/m³ (retained)
{prefix}/status/airquality/pm10	Publish	PM10 in µg/m³ (retained)
{prefix}/status/airquality/no2	Publish	NO₂ in µg/m³ (retained)
{prefix}/status/rssi	Publish	WiFi signal strength in dBm (retained)

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Command Format

The command topic accepts the same JSON protocol as WebSocket. Examples:

{ "type": "setLed", "led": 0, "on": true, "r": 255, "g": 0, "b": 0 }
{ "type": "setCycle", "cycle": true }
{ "type": "setParty", "party": true, "partyMadness": 7 }
{ "type": "setRainbow", "rainbow": true }
{ "type": "randomYesNo" }
{ "type": "weatherColor" }
{ "type": "airQualityColor" }
{ "type": "all_off" }

Also accessible via HTTP POST to /cmd.