(Help needed) KNX with Vimar Thermostate and NO Webserver- how to read the telegrams

Hello. Everyone,

I have started integrating the already existing KNX BUS System into HA. Is is an old system, connected to HA through a Weinzierl 730 IP Interface. Moreover VIMAR doesn’t directly use ETS, so I don’t have a Project file, only their proprietary software and DB-file.
The blinds were relatively easy, because they only have a stop and an up/down address.
But I have huge problems, because I only have three “obscure” addresses per thermostat
I am thinking that if I make changes to the thermostats through the physical display on the wall, and find the telegrams, I could extract the required address for the KNX integration.
I have searched the whole day for a way to get the telegrams from the IP Interface. Can someone please help me?
If someone has already configured a KNX from Vimar, only with the IP interface and WITHOUT the Webserver, some advice would be appreciated.

PS-I will update my post with model numbers and the available addresses.

ETS group address monitor will do the job.
Or you use xknx.telegram logger on debug - see knx Integration documentation

Thanks a lot for the advice.
EDIT: I’ve found one of your posts on the subject, from 2019. I will read further. Thanks again.
I have read about the ETS Monitor feature, but I don’t have ETS. I wanted to buy it, but than I realised that I don’t have the project for my BUS system and I decided that for my purposes, it isn’t worth the investment.
Can you please give me more details on the xknx option? I have only worked with HA after I bought the house, 2 months ago. As such, I am absolutely terrible at it.

Here’s the link Logging knx
ETS demo is free and would do.

Both the documentation and the tip with ETS6 Demo (how did I miss this?!) where really helpful. Now I only have to “filter out” what is NOT a thermostat or relay and how the telegrams are constructed. Still, a really good start. Thanks.

Unfortunately, I wasn’t able to understand anything useful from the log-files or the ETS Group Monitor.
I have added some new information, that could be useful.

What I currently have:
Thermostat Model: VIMAR 14514 Plana
Actor: VIMAR 01851.2

For each Thermostat, I have extracted the following (and only) information:

Because I am only allowed to post one Screenshot, I will reply to my own post.

Example of the Group Monitor Telegram, when changing the Thermostat target temperature:

In the VIMAR EasyTool Software, I can change some of the values that are required in HA, but I don’t know their addresses:

None of the addresses you posted appear in the short ETS monitoring screenshot. Did you change a different thermostat?
Maybe copy&paste the xknx log - it may not tell you much, but maybe I can read something out of it.

ETS doesn’t know how to decode the payloads so it just guesses. You could create a project and define the group addresses and their (supposed) DPT to better see what is happening.