SP2339的源代码，实现1个串口扩为3个串口的功能，代码实现数据的接收和发送功能，并可移植到其它环境中使用,修改时注意是否发送完数据后，还会一直处在发送中断里。-SP2239 s source code, a serial expansion of the functions of three serial code data receive and transmit functions, and can be ported to other environments to use.