51单片机实现目标板上 一串口到多串口的选择切换。

COMX下行口（接被监控设备）为16路RS232，上行口（接管理PC）为1路RS232或1路10BASE-T。

COMX支持四级级联。

包中源码为标准A51代码，可用KEIL直接编译生成可烧写文件，本设计应用目标芯片为at89s52。-51 MCU target board over a serial port to the serial port selection switches. COMX down mouth (then under surveillance equipment) for the 16-way RS232, uplink port (Hospitality Management PC) as a way RS232 or 1 10BASE-T. COMX to support four cascade. A51 source package as the standard code, can be used directly KEIL compiler generates Shaoxie documentation, the goal of chip design applications at89s52.