说明：  计算机中传输数据的方式有两种：并行方式和串行方式。在IBM PC机的汇编语言中，对串口的编程方式有DOS和BIOS 系统功能中断调用。本次实验设计采用BIOS系统功能中断调用，即通过INT 14H，调用ROM BIOS串口通信例行程序。
(computer transmission of data in two different ways : parallel and serial mode approach. IBM PC assembly language, the serial programming method DOS and BIOS interrupt function call. The experimental design using BIOS interrupt function call, through INT 14H, called ROM BIOS serial communication is a routine procedure.)