This code is possible thanks to the previous work done by @Ebiroll to program the RAK811 from Platformio. You can find his work here: https://github.com/Ebiroll/RAK811_BreakBoard
This code has been adapted to US915 band by @RussNelson https://github.com/RussNelson
This work is carried out within the project http://openmaker.eu/2018/02/05/fenps/ financed by the EU's HORIZON 2020 programme.
You can follow the instructions in the wiki page: https://github.com/jcaridadhdez/RAK811-tracker/wiki