MQTT channel not supported

Setup, Configuration and Use Items & Sitemaps
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1

Platform: RPI3 b+
OH 4.0.2 fresh Openhabian install
Java: 17

Hi,

I am struggling with setting up MQTT Things. I have some temperature sensors and their data is sent by my MySensors gateway via MQTT. I can read and attache temperature value to an Item easily, but whatever channel ID I set for other properties of the Thing I get Channel mqtt:topic:TempSensors:battery not supported! warn and Item doesn’t receive data. So the first channel property works but the second doesn’t. I tried several changes without success. Could you please give me some guidance what I do wrong?

I confog MQTT based on this tutorial, and I can’t see significant differences between Things configs: MySensors without the binding (DHT22 over MQTT)

Moquitto get all messages, so that shouldn’t be an issue

Screenshot 2023-09-10 at 21.01.12
Screenshot 2023-09-10 at 21.01.122036×1694 447 KB

Things definition

// MQTT Broker - MySensores 
Bridge mqtt:broker:MySensorsMqttBroker [ host="127.0.0.1", port="1883", secure=false ]

// MQTT - MySensors temperature sensors
Thing mqtt:topic:TempSensors "Tempereature sensors" (mqtt:broker:MySensorsMqttBroker){
	Channels:
		Type number : temperature "Temperature" [
			stateTopic="mysensors-gateway-out/27/0/1/0/0"
		]
		Type number : battery "Battery" [
			stateTopic="mysensors-gateway-out/27/255/3/0/0"
		]
}

Items definition

// Living Room
Number gf_living_heating_temp       "Nappali"           { channel="mqtt:topic:TempSensors:temperature" }
Number gf_living_heating_battery    "Nappali battery [%d %%]"   { channel="mqtt:topic:TempSensors:battery" }
2

What happens when you remove the [%d %%] ?

3

Maybe the changes to your Things files aren’t being picked up properly.

You can restart openHAB to see.

Or I do this.

4

try

// MQTT Broker - MySensores 
Bridge mqtt:broker:MySensorsMqttBroker [ host="127.0.0.1", port="1883", secure=false ]

// MQTT - MySensors temperature sensors
Thing mqtt:topic:TempSensors "Tempereature sensors" (mqtt:broker:MySensorsMqttBroker){
	Channels:
		Type number : temperature "Temperature" [ stateTopic="mysensors-gateway-out/27/0/1/0/0"]
		Type number : battery "Battery" [stateTopic="mysensors-gateway-out/27/255/3/0/0"]
    }
}
5

Thing UID should be like

mqtt:topic:MySensorsMqttBroker:TempSensors

and therefor the Channel UIDs should be

mqtt:topic:MySensorsMqttBroker:TempSensors:temperature
mqtt:topic:MySensorsMqttBroker:TempSensors:battery

If defining Things via text files, it’s more common to use hierarchic notation:

Bridge mqtt:broker:MySensorsMqttBroker [ // MQTT Broker - MySensores 
    host="127.0.0.1", 
    port=1883, 
    secure=false 
 ] {
    Thing topic TempSensors "Tempereature sensors"     // MQTT - MySensors temperature sensors
    {
	Channels:
		Type number : temperature "Temperature" [ stateTopic="mysensors-gateway-out/27/0/1/0/0" ]
		Type number : battery     "Battery"     [ stateTopic="mysensors-gateway-out/27/255/3/0/0" ]
    }

 }

Please be aware that port is numeric and therefor you should not use quotes for the value.

1 Like
6

I had this problem with items linked to Hue lights, removing the [%d %%] made the items work again.

7

Hi,
Your suggestion solved the issue. I restarted the device and after a while it started to work.
Thank you,
Attila