Introduction - If you have any usage issues, please Google them yourself
(1) the serial port setting file serial.c is encapsulated into a dynamic library.
(2) the use of dynamic library compilation to generate host_serial applications to verify the correctness of the dynamic library
(3) the serial port settings file is encapsulated into a static library.
(4) the use of static library compilation to generate host_serial applications to verify the correctness of the dynamic library