杨清-毕业论文（定稿）

毕业论文

智能热量表控制系统的设计—LCD显示

学 院 继续教育学院 专业年级 06级机械电子工程 学 号 013106410063 学生姓名 杨清 指导教师 荣梅 评阅老师 荣梅

中国·南京 2009年12月

摘 要

热量表（heat meter）是用于测量及显示水流经热交换系统所释放或吸收热量的仪表，热量表是安装在热交换回路的入口或出口，用以对采暖设施中的热耗进行准确计量及收费控制的智能型热量表。

本文主要介绍了以TI公司生产的MSP430系列单片机为核心、选取了以DV12864J为液晶显示模块的智能热量表控制系统的设计！智能热量表的设计是单片机开发系统的重要应用，该技术能简单快速的显示热量表的一些数据，主要应用于北方以热网集中供热的热量表仪器上，为取暖结算提供很大方便！主要元器件有MSP430系列单片机、DS18B20数字传感器、DV12864J液晶显示模块及其控制器ST7920等!本文首先简单介绍了热量表及其原理，其次详细阐述了我所选取的方案包括它的CPU核心、工作电压及温度传感器，然后介绍了LCD硬件模块DV12864J，最后列出了控制器ST7920的并口驱动程序！

关键词：MSP430单片机 DS18B20数字式传感器 DV12864J

Abstract

Calorimeter (heat meter) is used to measure and display water flow through the heat exchange system to release or absorb heat meters, heat meters are installed in the heat exchange loop entrance or exit to the heating facilities to accurately measure the heat consumptionand charges for the control of intelligent Heat Meter. This paper describes a production of TI's MSP430 series microcontroller as the core, selected in order to DV12864J liquid crystal display module of the Intelligent Heat Meter Control System!Intelligent Heat Meter is designed to be SCM important application development system, the technology can be simple and fast display Calorimeter some of the data, mainly used in the north to central heating of the calorimeter heating network equipment, the settlement provides a great convenience for the heating!The main components are MSP430 MCUs, DS18B20 digital sensors, DV12864J liquid crystal display module and its controller ST7920, etc.! In this paper, a brief introduction of the calorimeter and its principles, followed by the detailed program I selected, including its CPU core, the work ofvoltage and temperature sensors, and then introduced the LCD hardware modules DV12864J, controller ST7920 listed at the end of the parallel port driver!

Key words: MSP430microcontroller DS18B20 digital sensor DV12864J

目 录

第一章 绪论 .................................................................................................................. 1

1.1 热量表的简介 ................................................................................................. 1 1.2 本文主要内容 ................................................................................................. 3 第二章 方案选择 .......................................................................................................... 4

2.1方案的选择 ...................................................................................................... 4 2.2 LCD与LED的区别 ....................................................................................... 4 2.3 MSP430的简介 ............................................................................................... 5 第三章 系统的硬件模块 ............................................................................................ 7

3.1 电源模块 ......................................................................................................... 7 3.2 工作电压 ......................................................................................................... 7 3.3 复位电路 ......................................................................................................... 8 3.4 温度传感器 ..................................................................................................... 9

3.4.1 DS18B20的主要特性 .......................................................................... 9 3.4.2 DS18B20的外形和内部结构 .............................................................. 9 3.3.3 DS18B20工作原理 ............................................................................ 10 3.3.4 高速暂存存储器 ................................................................................ 11 3.5 LCD显示 ....................................................................................................... 12

3.5.1 液晶显示模块概述 ............................................................................ 12 3.5.2 模块引脚说明 .................................................................................... 13 3.5.3 接口时序 ............................................................................................ 13 3.5.4 用户指令集 ........................................................................................ 15 3.5.5 显示RAM ......................................................................................... 17 3.5.6 ST7920控制器 ................................................................................... 17

第四章 系统的软件 .................................................................................................... 20

4.1 ST7920控制器驱动程序 .............................................................................. 20 第五章 总结与展望 .................................................................................................... 28 致 谢 .......................................................................................................................... 29 参考文献 ...................................................................................................................... 29 附录 .............................................................................................................................. 31