说明：  Multisim 8可以将不同类型的电路组成混合电路进行仿真，界面直观，操作方便。本文先研究Multisim 8的操作方法及其应用实例。之后分别根据交通灯系统和出租车计价器系统的设计要求提出其改进的系统实施方案。然后根据两系统的改进方案，分别设计其数据子系统和控制子系统，并画出实现的电原理图，其中部分模块用VHDL语言实现。最后在Multisim 8中进行仿真，验证两系统的改进方案均正确实现了各自设计要求中的诸项功能。
(Multisim 8 will be different types of circuit composed of mixed circuit simulation, visual interface, convenient operation. This paper will examine Multisim 8 methods of operation and application examples. Respectively after traffic lights system and the taxi meter system design requirements of the system to improve its implementation of the program. According to the improvement of systems of two programs designed its data subsystem and control subsystem, and paint to achieve the circuit diagram, Some of these modules using VHDL. Finally in Multisim 8 simulation. 2 certification system improvement program are correct achieve their design requirements for the various functions.)