STM32F4串口程序,重定向C语言标准库函数pritnf和scanf到STM32F4的串口,这样程序中就可以使用printf和scnaf来做人机交互.-STM32F4 serial program, redirect C language standard library functions pritnf and scanf to STM32F4 serial, so the program can use printf and scnaf do human-computer interaction.