Suddenly after an HA update i get no sensor data anymore

[se-O-matic]

Hello,
After installing the Core Update 2026.7.4 HA did not received any data from all my "MySensors" sensors.

I use the serial gateway on a raspberry pi 3. The connection to this seems to work:

"2026-08-04 17:45:39.160 INFO (MainThread) [mysensors.transport] Connected to Serial<id=0x7f54ec9a50, open=True>(port='/dev/ttyUSB0', baudrate=38400, bytesize=8, parity='N', stopbits=1, timeout=0, xonxoff=False, rtscts=False, dsrdtr=False)"

I get no more messages from mysensors after the startup.
I tried a reboot as well as a shut down and a complete power cycle.
I tried to repower the sensors as well. But this doesnt work either.

Sometimes, about 2 to 3 times per day, i get a message like this:

2026-08-05 22:29:42.054 DEBUG (MainThread) [mysensors.transport] Receiving ��D������D��w���^y
2026-08-05 22:29:42.056 WARNING (MainThread) [mysensors.message] Error decoding message from gateway, bad data received: ��D������D��w���^y
2026-08-05 22:29:42.057 WARNING (MainThread) [mysensors] Not a valid message: not enough values to unpack (expected 5, got 0)

I tested the serial gateway on my pc. The sensors appear in the serial console:

8;0;1;0;0;21.59<\n>
8;1;1;0;1;58.98<\n>
8;255;3;0;0;85<\n>
5;0;1;0;0;23.40<\n>
2;0;1;0;0;19.05<\n>
2;1;1;0;1;68.34<\n>
2;255;3;0;0;63<\n>

I am running out of ideas. On github i also created a issue.
Has someone an idea how can i debug or fix this?
As last opportunity i can build a MQTT-Gateway.

regards,
Sebastian

[nagelc]

I'm not very smart at Home Assistant, but 2 things you could look at:
Your baud rate is being reported as 38400. My gateways run at 115200. I'm not sure how HA determines what the baud rate should be. Edit: for 8 MHz Arduino, 38400 baud rate is correct, so that probably isn't it.
In Home Assistant>Settings>System>Hardware, pick the System Hardware tab. That will show all the ports and what is attached to them. Maybe there will be a clue there.

[OldSurferDude]

Let us know how you are doing as you progress.

Are you running HA on the RPi 3? There have been many reports of HA bloating to beyond the capabilities of the RPi. If this is the case, you'll have to install HA on another computer.

I run HA in a virtual box which runs under the Ubuntu OS on a refurbished PC. (You can use an old laptop, too.) I believe that you can run HA on a PC "bare metal" too. If you have to go that route, we can help you.

[se-O-matic]

@nagelc said:

I'm not very smart at Home Assistant, but 2 things you could look at:
Your baud rate is being reported as 38400. My gateways run at 115200. I'm not sure how HA determines what the baud rate should be. Edit: for 8 MHz Arduino, 38400 baud rate is correct, so that probably isn't it.
In Home Assistant>Settings>System>Hardware, pick the System Hardware tab. That will show all the ports and what is attached to them. Maybe there will be a clue there.

Thanks for your hints. I checked this already. My sensors run at 38400 baud and i see in the debug log, that HA opens the port with the same baud rate.

@OldSurferDude said:

Are you running HA on the RPi 3? There have been many reports of HA bloating to beyond the capabilities of the RPi. If this is the case, you'll have to install HA on another computer.

yes, i run HA as HASSOS version on the RPI3. This worked very well until the one update do something with the mysensors integration.
This setup run till this date very smooth with a couple of ZigBee devices over the ZHA integration.

I already thought about running HA in a docker on my homeserver. This is a tiny HP PC (Old Elitedesk 800 G1 Mini) on which run debian and CasaOs.
I read about problems to get ZigBee working in a docker environment. I use the SonOff zigbee usb stick. And the mysensors serial gateway is connected over USB, too.

At least I have two possibilities, which both are very time consuming.

1. Build a ethernet gateway with or without MQTT. I already have a ethernet board ordered to test this. But i have to build this up an a breadboard for testing and i have to update every mysensors sensor to a fixed ID instead of the automatic assigning.
2. Migrate my homeserver from CasaOs to Zimas (CasaOs is deprecated ...) (btw, i have to do this anyway) and the test HA in a docker with routing usb devices to the container.