河南理工大学毕业论文 第 1 页 共 52 页
毕业设计报告书
河南理工大学毕业论文 第 2 页 共 52 页
基于单片机的温度采集系统
摘 要
现今，自动控制技术尤其是温度控制技术在国内外得到广泛的应用和发展。时滞效应始终困扰着其实际应用，为此人们发明了多种控制方法来解决时滞问题，例如比例控制方式、DDC控制方式，本文将针对一种温度控制方式进行学习，并设计一个以8051单片机为核心、利用新型集成化智能1-Wire总线数字温度传感器DS18B20实现的温度采集控制系统，同时还阐述了直接数字控制（DDC）中的最少拍控制算法。
本设计采用以8位8051单片机作为系统的CPU。使用电加热器升温，直流电机风扇降温，配合键盘输入，液晶显示器显示。具有硬件结构简单、人机界面友善、管理功能健全、系统可靠性高、记录数据准确、使用维护方便等优点。
本系统按照模块化程序设计思想，完成了对系统软件部分的设计，给出了各个功能模块的设计思想和流程图。温度采集控制控制系统不但能够准确地进行温度数据的采样转换，稳定进行升温、降温、恒温的控制过程，而且可以记录温度—时间对应关系，并以现今广泛使用的液晶显示器作为输出设备，使数据读取更加直观。现场实验表明，该系统在测试过程中工作稳定，满足设计要求。
关键字：温度采集控制系统；单片机；DS18B20；DDC
河南理工大学毕业论文 第 3 页 共 52 页
Abstract
Nowadays, the automatic control technique is a temperature particularly controls technique at domestic and international get the extensive application with develop. Time postpone effect perplex always in fact on the occasion of applied, for this person invents various controls method to resolve the problem of Time postpone. This paper introduces a design of temperature data acquisition system based on single-chip 8051. The system collects temperature data through 1-Wire Digital Thermometer DS18B20, and the control algorithm of fuzzy adjustment of DDC parameters is presented.
The temperature data acquisition and control system adoption with 8 8051 single a machine for system CPU. The usage electricity heating apparatus heats, the direct current electrical engineering fan reduces the heat, matching with the keyboard importation, displays with the LCD. It has simple structure, high system reliability, and the data recorded are reliable and the operation and maintenance are convenient. This system according to mold a design for turning procedure design toughing, completing to system software part of designs, giving each function mold piece thought with flow chart. A function temperature control system can proceed accurately the data adopts the kind converts, stabilizing the proceeding heat, reduce the heat, the control process of the constant temperature, and can satisfy completely to the request of the system accuracy. and can show them to the operators by the way of the Liquid Crystal Display. This system used the present the usage the LCD and actions output equipments, make data kept the view more. The results of the experiments show that the system works stably and meets the expected design requirements.
Key words: temperature data acquisition and control system；single-chip；DS18B20；DDC
河南理工大学毕业论文 第 4 页 共 52 页
目 录
引言 ····································································1 1 绪论··································································3
1.1 课题背景······························································3 1.2 立题的目的和意义······················································3 1.3 温度采集控制系统的预期功能和基本原理··································3 1.4 本系统主要研究内容····················································4
2 温度采集控制系统总体分析与设计···································5
2.1 温度采集控制系统的组成和工作原理······································5 2.2 温度采集转换系统······················································6 2.3 升降温控制系统系统····················································7 2.4 键盘显示系统··························································9 2.5 报警系统······························································9 2.6 电源系统·····························································10 2.7 硬件电路设计·························································10 2.7.1 系统硬件配置······················································10 2.7.2 主要元件简介······················································10
3 软件系统设计······················································22
3.1 软件总体设计························································22 3.2 系统初始化函数······················································23 3.3 控制函数····························································23 3.4 键盘显示函数························································24 3.5 降温函数····························································24 3.6 曲线算法····························································25 3.７ 采样································································26 3.８ 时间函数····························································27
4 调试与运行························································28 致谢····································································32 参考文献·······························································33 附录一系统源程序·····················································34
河南理工大学毕业论文 第 5 页 共 52 页