Location of firmware Source Code for AirGradient DIY PRO pre-soldered kit

I have an AirGradient DIY PRO pre-soldered kit. Although I located the webpage where one can directly flash the unit, I cannot find the actual firmware source code.

The GitHub repository seems to only have code for the PRO version and its display is oriented differently.


See here: Library code for DIY Pro not working correctly with the display - #4 by marmoset

But basically just change the _R3 to _R2 to fix the orientation.