If your windows / arduino can generate HTTP you can use https://github.com/Duet3D/RepRapFirmware/wiki/HTTP-requests. This is quite a straightforward interface, e.g. a GET of http://18.104.22.168/rr_gcode?gcode=G28 will execute G28 (ie home all) on the duet machine at 22.214.171.124. It has file operations (upload, download, list, delete etc.), execute arbitarray gcode, and let you get any part of the object model (which lets you check almost every element of the state or status of the machine).
If you install curl you can do this from pretty much any scripting language (even .bat files).
@selva_tvi Your tpost2.g has M568 P2 S1 with the comment to turn on mixing. However, M568 to turn on mixing was deprecated a long time ago and M568 is now used for tool settings. So if you are using firmware 3.3. beta 2 or later, then M568 P2 S1 will set the active temperature for tool 2 to 1 deg C, which is consistent with the behavior you are seeing.
I suggest you remove or comment out and M568 commands or use them to set the desired temperature as per the documentation https://docs.duet3d.com/User_manual/Reference/Gcodes#m568-set-tool-settings
@hackinistrator thanks for your reply and sry for my delayed answer. Leadscrews aren't an option as I have to stick with the rotating movement instead of linear movement of the axis because it drives another belt.
The motors are running at 24V.
Yes, I need 2Nm roughly to be able to move the axle. I have a gear ratio of 5:1 with 1/8 microsteps and two 1.9Nm Motors which leaves me with 3.7Nm left if 19,51% of the max power of the motor is preserved through 1/8 microstepping regarding the faulhaber website.
In theory and in praxis this is enough, the motor is working fine now. Only thing that I've pin pointed is that the timing belt is flexing too much and I am working on a solution for this at the moment.