本串口通信例程的功能主要演示AX516/AX545开发板的uart接收和发送的功能，在程序没有接收到PC机发来信息的时候,串口会不断的通过串口向PC机发送”Hello ALINX AX516”的信息。当用户从PC机发送数据给AX516/AX545开发板，程序接收到数据后会把数据从串口发回给PC,从而实现Loopback的功能。-The main function of this presentation uart serial communication routines AX516/AX545 development board receive and transmit functions, while the program does not receive the information sent by the PC, the serial port through the serial port will continue to send " Hello ALINX AX516"　to the PC information. When the user data transmitted　the PC to the AX516/AX545 development board, the program will receive the data　the serial data back to the PC, in order to achieve the Loopback functions.