Some time ago I tryed to use a simple C winapi window to comunicate to Arduino using serial. I used information on https://playground.arduino.cc/Interfacing/CPlusPlus . The results was a .dll file that may be included in some project. I used VC6 to compile. Results in 3 files: dllCOM.dll, dllCOM.h and dllCOM.lib.
dllCOM.zip (47.1 KB)