I'm using the NodeMCU 1.0 (ESP-12E Module) board as my first venture into using the Arduino platform, and I would like to learn more about the internals of the Arduino software that stands between my programs and the C++ compiler. Can anyone tell me where I should look for this kind of information?
For example: I'm using the "WRITE_PERI_REG" function extensively in my code, and would like to understand how it is implemented. Can anyone point me to where I would find the source code that implements this function? All clues appreciated!