Hi, I meet some diffcult when try to create a project having multi files in /src and /include folder.
I have see some discuss but they don’t solve my problem…
For simple, I create main.cpp and test.c in /src folder and test.h in /include.
and their content is
but when I build the project, an error saied ‘Serial’ undeclared. As I known, boath Serial and pinMode, LED_BUILTIN, millis() are Arduino built in function. Why only Serial is unrecognized and how to solve it…
by the way, my platform is ESP32, but I also tried Arduino UNO and they don’t work neither…