Modbus "Servicename(ARG)"

Hello,
i configure my openhab2.4 in my raspy3B+.
I use only paper UI, and i can’t use a service trasformation for Modbus input.
Is there a solution to transform modbus data (in my case I have to divide the number by 2) without having to write code ?? I’m a newbie in programming.
Thank you all.

The short answer is no. This is going to require a little bit of code. You can create a Rule or you can create a JS Transformation.

1 Like

The Modbus docs include an example for divide by 10. It’s not that hard to adapt; have a try and come back for help if you need it.

1 Like

thank you very much for helping.
My problem, following the guide, is that on Raspberry I don’t know where to find the file to compile, of which the beautiful guides speak.
Also to add tags to items, I used restAPI which does it automatically.

I don’t know which file you are talking about. There is no compilation involved here.

transform overview:

You create a text file, called dividebytwo.js or something like, and put it in your openHAB /transform/ folder.

You’ll need a text editor of some kind to put javascript into that file. That’s the script that will take the raw data from the binding, do something to it, and return a value to the binding. There’s no compiling, this script gets interpreted at runtime.

Then you add a read transform parameter to your binding data Thing that describes the kind of transformation you want to make - JS - and the file you want it to use - dividebytwo.js

Um, okay. There are no tags involved here.

thank’s. i try it.

with notepad i have creata a file “dividebytwo” and put it in folder /trasform/ (OK, i make it with windows,

).
After with paperUi i have write it:
.

but don’t work… what i havn’t understand???

Thank’s a lot

Okay, you need to give it some content as well - the actual javascript.
The docs include an example for divide-by-ten. You can modify that for divide-by-two.

When doing this sort of thing, you should keep an eye open for relevant messages in your openhab.log and events.log files.

1 Like

thank’s a lot.
i don’t know why, but i have resaved a file, and now work!!!
!!

thank you very much

1 Like