《智能去电控制器的设计(毕业论文)》.doc

大学生本科毕业设计（论文） 题目：智能去电控制器的设计 领域：电子通信类 日期：05年6月 类型：精选 作者：杨佳沛摘 要 随着办公自动化的发展，越来越多的公司选择了组建本公司的局域网电话系统，从而达到提高公司整体工作效率和节约通信费用的目的。这种电话系统一般有一台总机和若干台分机组成，主机有一个固定的公用电话号码，若干分机各有自己的局域网号码，当其他公司或单位的电话打进本公司时，首先是主机接到来电号码，主机判断来电是打给公司哪个部门的，完成判断后就将来电转到相应的部门，来电呼叫处理完毕。对于打进公司的电话，由于不是公司支付通信费用，一般单位对此无限制，当公司内部需要打出电话时，由于通信费用完全是公司自己支付，为了避免公司的员工把公司的电话私用，就必须对去电进行区分和权限限制，可以通过设置黑名单或者白名单控制某个电话的能够打出或者禁止。本项目主要是单片机控制去电电话，即根据主叫所拔的号码，通过检测存储器预设的黑名单或者白名单控制某个电话的能够打出或者禁止，或者控制某一局向号，来确定能否打出。该系统单片机控制核心系统软件采用汇编语言编写，主要由、程序组成。Abstract With the development of office automation, more and more companies build up the local area calling network of itself, in order to increase efficiency and decrease the communication cost. This calling system is generally composed of a master telephone and several extension telephone numbers. The master telephone has a fixed number, and the several extension telephones have their own numbers in the network. When the outside phone dials, the master telephone firstly receive the call and decide the department which the call is to, then the call is transferred to the department. Because the outside call is not pay by the company, the company need not limit the call. When the workers of the company call the outside, the communication cost is pay by the company. In order to limit the workers using company phone to call the not relative numbers, the company should set limits of authority to discriminate the white numbers from the white numbers. This project mainly use the microcontroller to control the inside call which is to the outside. The microcontroller discriminate the white numbers from the black numbers . AT89C51 is CPU of this system, and it is core of this system. This system uses 74LS373, 74LS138, 7404, DAC0832 to discriminate the white numbers from the black numbers. Software of this system is programmed by assembler language and it is mainly composed by main program, subprogram of generation of the inside phone number , subprogram of discriminating the white numbers from th