例子程序名为Terminal，是一个简单的TTY终端仿真程序。读者可以用该程序打开一个串行口，该程序会把用户的键盘输入发送给串行口，并把从串口接收到的字符显示在视图中。-example program called Terminal, is a simple TTY terminal emulation. Readers can use this program to open a serial port, the program will be user keyboard input sent to serial port, and from the serial port to receive the characters shown in the view.