【正文】 可以用于溫度、濕度等非電信號的測量，能獨(dú)立工作的單片機(jī)溫度檢測、溫度控制系統(tǒng)已經(jīng)廣泛應(yīng)用到很多領(lǐng)域。對本科生畢業(yè)設(shè)計（論文） 2 于不同場所、不同工藝、所需溫度高低范 圍不同、精度不同，則采用的測溫元件、測溫方法以及對溫度的控制方法也將不同；產(chǎn)品工藝不同、控制溫度的精度不同、時效不同，則對數(shù)據(jù)采集的精度和采用的控制算法也不同。在溫度控制器中應(yīng)用單片機(jī)，具有設(shè)計簡單、可靠性高、控制精度高， 功能易擴(kuò)展， 有較強(qiáng)的通用性 等優(yōu)點(diǎn)。溫度傳感器應(yīng)用范圍很廣、使用數(shù)量很大，但是在常規(guī)的環(huán) 境參數(shù)中由于溫度受其它因素影響較大，而且難以校準(zhǔn)，因此，溫度也是最難準(zhǔn)確測量的一個參數(shù)。它迅猛的發(fā)展到了各個領(lǐng)域，人們也越來越感到應(yīng)用單片機(jī)技術(shù)的優(yōu)越性，因而單片機(jī)也得到了廣泛的應(yīng)用。 關(guān)鍵詞 ： 單片機(jī)；恒溫；控制；報警； PID Abstract In recent years, microcontroller is developed very rapid,microcontroller applications have perated into various the measurement and control of temperature bees more and more important, the temperature control has a positive significance in various traditional method of temperature acquisition is not only timeconsuming and laborious, but poor accuracy,the emergence of microcontroller makes the problem of data acquisition and processing temperature can get very good using microcontroller to control temperature is not only easy to control, simple, flexibility and other characteristics, but also can greatly improve the temperature which was charged with technical indicators, which can greatly improve the quality of the product. Thermostatic control play a decisive role in the process of industrial production, temperature control directly affects the yield and quality of industrial design is the constant temperature box control system based on AT89C51 microcontroller, the system is divided into two parts of hardware and software,the hardware includes:temperature sensor,display,control and alarm design。所以采用單片機(jī)對溫度進(jìn)行控制不僅具有控制方便、簡單、靈活性大等特點(diǎn)，而且還可以大幅度提高被控溫度的技術(shù)指標(biāo)，從而能夠大大提高產(chǎn)品的質(zhì)量。 摘 要 近年來單片機(jī)發(fā)展十分迅速，單片機(jī)的應(yīng)用已經(jīng)滲透到各個行業(yè)。 本設(shè)計是基于 AT89C51 單片機(jī)的恒溫箱控制系統(tǒng)，系統(tǒng)分為硬件和軟件兩部分，其中硬件包括：溫度傳感器、顯示、控制和報警的設(shè)計；軟件包 括：顯示程序設(shè)計、控制程序設(shè)計和溫度報警程序設(shè)計。software includes:a display program design, programdesign and temperature alarm program design. Write a program bining hardware debugging,can realize the setting and adjusting the initial temperature, for display, alarm immediately when heated to the set design from practical application selected small,relatively high accuracy digital temperature sensor DS18B20 as the temperature logger,AT89C51 microcontroller as the master chip, LCD1602 as display output,and also contains the PID algorithm,realize the realtime measurement of temperature and constant control. Keywords： microcontroller； thermostat； control； alarm； PID I 目 錄 第 1 章 緒論 ..................................................................................................................... 1 課題背景 ............................................................................................................. 1 課題意義 ............................................................................................................. 1 課題內(nèi)容 ............................................................................................................. 2 恒溫箱的發(fā)展與趨勢 ......................................................................................... 2 本文結(jié)構(gòu)安排 ..................................................................................................... 3 第 2 章 系統(tǒng)概述 ............................................................................................................. 4 設(shè)計思路分析 ..................................................................................................... 4 系統(tǒng)需求分析 ..................................................................................................... 4 方案選擇 ............................................................................................................. 5 恒溫箱的工作過程 ............................................................................................. 6 本章小結(jié) ............................................................................................................. 6 第 3 章 系統(tǒng)硬件設(shè)計 .................................................................................................... 7 硬件電路設(shè)計概述 ............................................................................................. 7 系統(tǒng)功能介紹 ..................................................................................................... 8 時鐘頻率電路設(shè)計 ............................................................................................. 8 顯示電路的設(shè)計 ................................................................................................. 9 開關(guān)鍵盤設(shè)計 ....................................................................................................11 溫度報警電路設(shè)計 ........................................................................................... 12 溫度采集電路 ................................................................................................... 13 本章小結(jié) ........................................................................................................... 19 第 4 章 系統(tǒng)軟件設(shè)計 .................................................................................................. 20 軟件任務(wù)分析 ................................................................................................... 20 程序流程圖 ....................................................................................................... 20 II 系統(tǒng)控制算法 ................................................................................................... 24 參數(shù)整定 ........................................................................................................... 26 本章小結(jié) ........................................................................................................... 27 結(jié) 論 ............................................................................................................................... 28 參考文獻(xiàn) ......................................................................................................................... 29 致 謝 ......................................................................................................