Serial binding says port is not known /dev/ttyUSB0

Setup, Configuration and Use Installation
1
  • Platform information:
    • Hardware: Raspberry Pi 4, 8GB
    • OS: Raspbian OS 64 Bit
    • Java Runtime Environment:
root@raspberrypi:/dev# java -version
openjdk version "11.0.10" 2021-01-19 LTS
OpenJDK Runtime Environment Zulu11.45+27-CA (build 11.0.10+9-LTS)
OpenJDK 64-Bit Server VM Zulu11.45+27-CA (build 11.0.10+9-LTS, mixed mode)
  • openHAB version: 3.0.2, running in Docker
  • Issue of the topic:

I’m running Openhab 3.0.2 inside a Docker container. I’m able to access the console of the Openhab installation. I’m able to read out /dev/ttyUSB0, but the Serial binding notify that the port /dev/ttyUSB0 is not known. What do I have to do, to access the Serial interface in Openhab?

  • Please post configurations (if applicable):
UID: serial:serialBridge:c06017d258
label: Serial Bridge
thingTypeUID: serial:serialBridge
configuration:
  baudRate: 9600
  charset: UTF-8
  serialPort: " /dev/ttyUSB0"
  dataBits: 8
  stopBits: "1"
  parity: N
2

Have you mapped the device to the container. I have something like that:

devices:
      - "/dev/ttyUSB0:/dev/ttyS0"

in my docker-compose.yml.

Maybe the leading space in the serial port definition?

Other things you can check:

  1. Is the device /dev/ttyUSB0 defined?
  2. Is the device readable and writeable by the user running openhab?
3

Thank you franks for your fast reply.
The leading space in front of /dev/ttyUSB0 doesn’t do anything
And the device is defined, because I can read the serial communication via cat /dev/ttypUSB0
How can I check if the device is readable from user running openhab?
My openhab instance is running inside a Docker container. And I’m able to start command line inside openhab docker container. And I can read all data there as well. But not possible to attach this signal into Openhab things definition.

4

From inside the container? See my edited answer before.

As you, it seems, already have. Open a shell inside the running container and do the cat /dev/ttyUSB0 from there. As you can see, I mapped the outside device (/dev/ttyUSB0) to the standard serial port #1 (/dev/ttyS0). But this should not make a difference.

5

I am able to read from inside the Container using cat /dev/ttyUSB0
I had a mapping in my docker compose

6

Any ideas left?
I really need to get this thing done :slight_smile:

7

I solved this issue by not using the serial binding in openHAB. I use the following library which receives/sends the serial port data. In my case the port /dev/ttyUSB0 on raspi4 is not available in openHAB. I send commands from openHAB over MQTT to the MQTT-IO library which then sends/receives data over serial port: