基于单片机的电表抄表系统摘要自动抄表是指采用通信和计算机网络等技术自动读取和处理表计数据。
发展电能自动抄表技术是提高用电管理水平的需要,也是网络和单片机技术迅速发展的必然。
采用自动抄表技术,不仅能节约人力资源,更重要的是可提高抄表的准确性,减少因估计或誊写而造成账单出错,使供用电管理部门能及时准确获得数据信息。
本例中介绍的抄表方案可方便移植到煤气表、水表等各种智能抄表系统。
本例抄表系统主要由主站端数据采集计算机、客户端基于单片机的抄表模块、计量电表三部分组成。
客户终端单片机模块和数据采集计算机通过RS-485串行通信口连接,实现数据传输。
本例中被测量的电表为威胜3型电表。
本例主要介绍客户端基于单片机的电表抄表终端的设计和实现方案在设计本例抄表系统时,以上功能均需要满足,其中主要部分是供电方式设计、数据掉电保护。
功能设计、终端抄表模块与数据采集计算机通信协议设计、实时时钟功能设计。
其中终端单片机抄表模块主要功能如下:采用三相四线(3x220/380V)供电方式,在三相交流电压断一相或二相的条件下,交流电源能维持终端正常工作,并且系统具有备用电池供电功能;具有实时测量用户用电电量功能;具有掉电数据保护功能,能保存用户用电电量信息。
支持DL/T—645电表通信规约。
终端和数据采集计算机通过RS-485通信,终端和主站通信具备数据完整性认证机制以保。
终端具有实时时钟功能,并且有对时功能。
关键词:单片机;抄表系统;串行通信;Based on SCM meter meter-reading system东北林业大学毕业设计AbstractA utomatic Meter Reading, AMR Meter (where) refers to the communication and computer network technology such as Automatic Meter Reading and processing data. Energy automatic meter reading technology development is to improve the management level of electricity, network and the technology rapid development. Adopting automatic meter reading techniques, can not only save manpower resources, more important is to improve the accuracy of the meter, and transcribed estimated or electricity bill, make mistakes in a timely and accurate management department can obtain information. In this example the meter reading scheme can be introduced to gas meter, convenient wait for all sorts of intelligent long-distance meter reading system. The meter reading system mainly consists of the host computer and data acquisition based on SCM client module, measuring meter meter three components. Client terminal single-chip computer and data acquisition module by RS - 485 serial communication, data transmission. In this example the meter is measured in type - 3 meters.This major is introduced based on SCM client terminal of the meter meter in design and implementation scheme design of the meter reading system, above all, to meet function main part of power supply is designed, and data protection. Functional design, terminal meter data acquisition module and computer communication protocol design, functional design of real-time clock.One terminal chip meter main function modules are as follows:adopts three-phase four-wire (3x220/380V power supply, in three-phase) ac voltage phase or break a two-phase conditions, the ac power can maintain the normal work and terminal system has a backup battery power function.with real-time measuring electric power users.has the power to save data protection function, electricity power userssupport DL/T -- buttons meter communication protocols.terminal and data collecting computer through the rs-five 485 communication, terminal and host communication with data integrity in the authentication mechanism.terminal with real-time clock function, and a readier function.Keywords: SCM, The computer, Serial communication, C language,2目录摘要Abstract1 绪论 (1)1.1 本课题的研究背景 (1)1.2 电表抄表系统的国内外研究动态 (1)1.3 电表抄表系统的目的及意义 (3)2 系统的总体设计 (4)2.1 系统的组成 (4)2.2电表抄表系统的功能说明及论文要求 (4)2.3电表抄表的关键问题 (5)3系统的电路设计 (6)3.1 单片机简介 (6)3.2技术方面具体体现 (6)3.3 RS-232和RS-485穿行通信设计 (14)3.3.1串行通信的作用 (14)3.3.2技术方案 (15)3.4 通信协议设计 (15)3.4.1通信协议的作用 (15)3.4.2 技术方案 (16)3.5 抄表系统电路图 (19)4 软件的实现 (20)4.1串行通信的基础知识 (20)4.1.1串行通信的数据传输 (20)4.1.2串行通信的数据转换 (20)4.1.3串行通信协议 (22)4.2 RS-232和RS-485串行通信设计 (23)4.3系统通讯方式实现 (26)4.4掉电数据保护的软件实现 (27)4.5数传终端的软件实现 (27)4.5.1AT指令的调试 (26)4.5.2程序的设计 (27)5结论 (32)参考文献附录致谢11基于单片机的电表抄表系统1 绪论1.1 本课题的研究背景目前,我国城乡居民用户抄电表、水表和煤气表的方式基本上都是人工抄表,即由抄表人员每月逐户查抄水表、电表、煤气表。