由于普通单片机只有一个串口,由于用户可能会用到多个串口,而对于双串口的单片机价格贵,不如自己动手选择两个IO口,自己模拟串口通讯,以下为模拟串口程序.-Because there is only one common single-chip serial port, as the user might use multiple serial ports, dual serial ports for the price of your microcontroller, it is better t