[WIP] Nordstar AC TN-X NORX-10CHSD/ZA31 - OpenBeken TCL driver

Hello!
I just got an AC installed 2 days ago and found it very similar to the Della Minisplit (see https://www.elektroda.com/rtvforum/topic4119999.html ). The app was some smarthome TCL thing powered by tuya so it matched even further what was documented on that forum post. It seems like this model is available in some places in the Balcans and Iberia including Greece.
Pictures make it seem very similar inside too.

Here is a Greek Marketplace where you can find retailers that sell this Unit.
https://www.bestprice.gr/item/2163894640/nord...tu-a-plus-plus-plus-a-plus-plus-me-wi-fi.html

Specs
Performance

Nominal Capacity: 10,000 BTU

Cooling Capacity: 10,165 BTU

Heating Capacity: 10,711 BTU

Coverage Area (Approximate): 25 sq.m.

Energy Efficiency

Energy Class (Cooling): A

Energy Class (Heating): A

SEER (Seasonal Energy Efficiency Ratio): 6.3

SCOP (Seasonal Coefficient of Performance): 5.1 W/W

Annual Power Consumption

Cooling: 283 kWh/year

Heating: 1,400 kWh/year

Dimensions (Width x Height x Depth)

Indoor Unit: 910 mm x 294 mm x 206 mm

Outdoor Unit: 853 mm x 602 mm x 349 mm

Noise Levels

Indoor Unit: 19 dB (Quiet operation)

Outdoor Unit: 50 dB

General Features

Technology: Inverter

Refrigerant: Eco-friendly R32

Connectivity: Wi-Fi Ready

Air Quality: Built-in Ionizer and Air Purifying Filters

Modes: Includes Dehumidification mode

Color: White

It has a TCWBRCU1 WiFi Module inside which I backed up the firmware for(not sure if this applies to all modules but my module was able to enter bootloader mode shorting rx and A0 together) and for me it is currently running openbeken (Built on Jun 7 2026 14:50:01 version 1.18.291).
I followed the guide from https://www.elektroda.com/rtvforum/topic4125928.html

However I am stuck figuring out how to configure this. Specifically I cant do it from the webui and I needed to make a autostart script and I have startDriver TCL in it.
The current driver seems to turn on the ac but isnt able to set temperature or read it? I also have not figured out how to connect it to home assistant. When setting temperature it seems to do a double beep and turn off.

So I need to figure out how to read serial from the driver RX on openbeken and how to correctly load in the device drivers. Then once all signalling issues have been fixed a guide along with documentation can be written for this adding one more AC to the device compatability of openbeken.

Any help would be appreciated!

Welcome to forum, sorry for the delay.

Can you share 2 MB firmware backup?

What do you mean by "can't do it from webui"? How do you know it's supported by TCL driver? Can you make some screenshots from your configuration?

notupus wrote:

The current driver seems to turn on the ac but isnt able to set temperature or read it?

Can you double check? It could indicate that wrong mode is set or protocol is slightly different....

@divadiow do you think you'd be able to flash his backup to dev board and check? It's just a suggestion, don't worry if it's too problematic, we could try different approach.

interesting.

another TCWBRCU1 AC has been posted about here https://www.elektroda.com/rtvforum/viewtopic.php?p=21916056#21916056 recently and the TCL driver doesn't appear to be right for that either.

Attached are all the files I got.
What I can't do from the webui is press the copy device settings and make it do something



I remember reading that I need to do something with GitHub Actions, but I haven't figured out what I would need to configure in the files of the repository in that case.

I think the TCL driver works because setting ACMode 1, it goes into cooling mode at 16 C( mentioning this in case it is relevant since I haven't figured out what is the default value it sends to the AC. If it does send something) At least based on my understanding, I found this reverse engineering of the TCL protocol and the 0x03 command seems the same since power and buzzer and display work correctly (based on the documentation at https://github.com/adaasch/AC-hack whiles yes this isn't openbeken it still somewhat seem to be the same thing), so my idea that the TCL driver could work is that it works partially.

What seems different is that Tuya seems to have had exposed 0.5 C target temperature steps. I haven't still figured out what my AC reports back since I don't see any raw serial messages in the logs.

The only configuration I was able to make is my home SSID and the autoexec.bat as follows

we can already see a difference. the tcl driver is fixed at 9600 baud but your dump is expecting 115200

That I also noticed and I wanted to change the baud in the driver to test it out but before that ACmode 1 turns the ac to cooling mode at 16C so maybe the controller has autobaud in rx? It's quite confusing to me right now since it shouldn't work but it works to some extent. But thanks for reminding me since when I parsed the 2MB file and when I did the tests there was a bit of time in between so I forgot that this was a discrepancy.

Is there a way to dump incoming serial to logs and set baud from commands? Ignoring the TCL driver for now until I figure out how to compile with custom baud and some debug output?

Added after 1 [hours] 14 [minutes]:

At 115200 baud ACmode does not work but it does in 9600.

GPT/Ghidra says:
TuyaOS/GFW-derived internal MCU bridge protocol
A5-framed, CRC16-protected, DP/identifier-oriented
not classic TuyaMCU
not OBK TCL BB protocol

Added after 35 [minutes]:

matching pk

nn2ooaacswz6uyi0

/schema

e1k5wioo

/dpIDs for the dump posted above
https://github.com/make-all/tuya-local/issues/3695

Added after 2 [minutes]:

https://github.com/search?q=nn2ooaacswz6uyi0&type=code