[modbus.lambda] Initial contribution

[chilobo]

Based on the Stiebel Eltron bundle by Paul Frank I contribute a bundle to manage Lambda Heat Pumps as a OSG addon to the Modbus Binding.

See the README.md for restrictions on usage.

The binding is based on the Modbus description of the manufacturer:
(https://lambda-wp.at/wp-content/uploads/2025/04/Modbus-Beschreibung-und-Protokoll.pdf)
A few parts of the description are not implemented. If you feel you need them, just open a request.

Fixed all feedback from #18330 and closed old PR due to Signoff/Rebase issues

Edit: Supersedes: #18330

[Copilot]

Pull Request Overview

This PR introduces a new Lambda Heat Pump binding as an OpenHAB add-on to the Modbus binding, allowing integration with Lambda Heat Pumps through the Modbus TCP/IP protocol. The binding is based on the Stiebel Eltron bundle and supports various heat pump components including heat pumps, boilers, buffers, heating circuits, and solar thermic components.

• Adds complete Lambda Heat Pump binding implementation with modbus integration
• Supports multiple heat pump system components with configurable subindexes
• Includes comprehensive channel definitions for all component types

Reviewed Changes

Copilot reviewed 55 out of 55 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
bundles/pom.xml	Adds lambda module reference to parent POM
features/openhab-addons/src/main/resources/footer.xml	Registers lambda binding in feature bundle
bundles/org.openhab.binding.modbus.lambda/*	Complete binding implementation including handlers, parsers, DTOs, configurations, and XML definitions
bom/openhab-addons/pom.xml	Adds lambda binding dependency to BOM
CODEOWNERS	Assigns code ownership for lambda binding

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}

[chilobo]

Hopefully this binding can now be merged - thanks to isiepiel and hist help.

[lsiepel]

There are about 20 build warnings that need to be fixed.

[chilobo]

Build warnings:
There are only 4 types of warnings:

1. Potential null pointer access: The variable myconfig may be null at this location:
   The parent OSGI-bundle of modbus is using the same code, so if somebody fixes this there I will copy it.

2. Type safety: The method toUnit(javax.measure.Unit) belongs to the raw type org.openhab.core.library.types.QuantityType. References to generic type org.openhab.core.library.types.QuantityType should be parameterized:
   I copied this from the stiebeleltron bundle. I am not capable of fixinig it.

3. getInt16Value(org.openhab.core.types.Command) from the type ... is never used locally:
   I changed this code into a comment because I might have to use it if Lambda adds values to these sections in the future

4. The value of the field *.AbstractBasePoller.logger is not used:
   I added a logger.trace to show that the corresponding poller is initiated and delete the unused loggers.

[chilobo]

@isiepel:
Could you look into
https://github.com/openhab/openhab-addons/actions/runs/18137231967/job/51619015639#step:8:2255
The build shows an error with openhab-addons/openhab-addons/bundles/org.openhab.binding.mqtt
Do you think I messed something up after merging openhab/main or has somebody else has to clean this before the build with my binding will go through?

[lsiepel]

Do you think I messed something up..

No, it is unrelated to this PR. It should be fixed now.

[chilobo]

I had to correct errors regarding the registers >= 50 in all parts and pushed the changes.

[lsiepel]

These comments are about fixing the last warnings and SAT errors.

[lsiepel]

JFTR, about 5-6 comments are not yet addressed from the last review round. They are burried under the 'Load More' button.

And the build is failing due to a missing import.

[chilobo]

These missing imports are caused by the changes you suggested:
Objects.requireNonNull
What do I have to import?
You suggested these changes in only three handlers. Should I change them in the other ones too?

[lsiepel]

Objects.requireNonNull

import java.util.Objects; just for the files that use the Objects.require....

[chilobo]

I added the code in all occurences of myconfig = ....

[lsiepel]

Thanks, LGTM.

Now, you could add the binding's logo to the openHAB website. See https://www.openhab.org/docs/developer/addons/#add-your-add-on-s-logo-to-the-openhab-website

(waiting for the build to finish.

[chilobo]

I asked the support of Lambda if it is allowed to use their Logo...

[chilobo]

I asked the support of Lambda if it is allowed to use their Logo...

... and they send me several logos. I added one of them in
https://github.com/openhab/openhab-docs/pull/2593
This pull request went through but ....

In the Documentation it says:

After your binding's pull request has been merged, you can upload your logo by filing another pull request to the openhab-docs/images/addons/ (opens new window) repository. Your logo will be available after the next website build.

We'll see how to add the link to the merged pull request of the binding ....

[chilobo]

@isiepel: Could you point me to some explanation: How do I connect the binding to the Icon in
https://github.com/openhab/openhab-docs/pull/2593

[lewie]

Hello @lsiepel, I have registered you for this minor change for review. I hope that was correct.
Many thanks.
#19749

[lsiepel]

@kaikreuzer can you add @chilobo to the contributor group ?

[chilobo]

Added handling of swapped DWords of VdaE and VdaQ in some heat pumps
as mentioned in
(#19749)
with a new pull request
(#19835)

[openhab-bot]

This pull request has been mentioned on openHAB Community. There might be relevant details there:

https://community.openhab.org/t/openhab-5-1-release-discussion/167620/261