【正文】 的特點，在工業(yè)控制的實踐中得到越來越廣泛的應用 。 課題研究的目的及意義 目前市場上家用燃氣鍋爐 大部分 為進 口，價格 較 高，售后服務 也 不夠完善，不利于燃氣鍋爐的推廣 與 使用，研制燃氣鍋爐的 企業(yè)與公司也 相對較少。隨著計算機和信息技術的高速發(fā)展， 單片機 廣泛的應用于工業(yè)控制中。由于加熱元件工作由外部電氣開關控制，所以啟停速度快。不需要布管路，沒有燃燒室、煙 道，不會出現(xiàn)燃煤、燃油、燃氣的泄漏和爆炸危險。 2） 無污染。Liquid CrystalDisplay。 關鍵詞 ： 單片機； 溫度控制 ； DS18B20； 燃氣鍋爐 ； LCD； 安徽建筑 大學 畢業(yè)設計（論文） ABSTRACT According to the market demand and the characteristics of domestic heating, this paper develops MCU intelligence controller for the minor gasfired boiler which is domestic heating equipment on the basis of investigation of heating demand widely. The research purpose is to change the inconvenience of temperature control bring by using coal fired boiler for centralized heating, to increase economics of software called Protel99se for circuit designed is used to develop the hardware of the controller. The hardware includes the power supply circuit, the reset circuit,the clock circuit, the alarm circuit, the LCD display circuit, and the temperature collection which is the core of this controller. The threepin integratedcircuit voltage regulator W7800 (7900) series ponent 7805 is used for the power supply. The Atmel AT89S51 chip is the core chip of the controller. The integrated temperature sensor DS18B20 is used to measure water temperature in boiler. The key circuit is used to set the alerm temperature and analog water in or out. In addition, LCD is used to display water level bound, current water level, temperature alerm value by presupposition and current temperature. When water level beyond its bound or when current temperature beyond its alerm value, the system gives an alerm and makes boiler burner off. When water temperature is down, the system releases alerm and makes boiler burener on. The system does it again and the system can save energy and improve energy utilization rate. Aim at the demand and characteristic of the system, on the basis of these hardware and implement method, using assemble language, system designs boiler temperature control system design based on singlechip. This software includes temperature and water level monitor main program, temperature collection subprogram, analoy water in and out subprogram, keyboard scan subprogram, LCD display subprogram etc. Keywords:MCU。等待溫度降到下限值，這時就可以重新鍋爐燃燒器通電，繼續(xù)加溫，如此反復監(jiān)控溫度。利用 Protel99se 軟件 設計電路 ，對智能控制器的電源電路、報警電路、時鐘電路、復位電路、 LCD 液晶顯示電路以及控制器的核心 — 溫度采集電路進行了設計。電源采用三端集成穩(wěn)壓器 W7800 (W7900)系列元件 7805,交流 220 v電壓轉換為單片機所需要的 5V電壓；利用 AT89S51 作為控制器的核心器件；利用集成電路溫度傳感器 DS18B20 測量鍋爐水溫 。這樣就可以提高能源的使用率 ， 節(jié)約能源。 Temperature control。 安徽建筑 大學 畢業(yè)設計（論文） 目 錄 1 緒論 ....................................................................................................................................1 課題背景 ................................................................ 1 ..................................................... 2 ....................................................... 2 2 系統(tǒng)方案選擇及工作原理 ......................................................................................................4 系統(tǒng)設計方案 ............................................................ 4 系統(tǒng)結構框圖 ............................................................ 5 ..................................................... 7 輔助器件選擇 ....................................................... 7 3 硬件電路設計 ........................................................................................................................8 主控單片機 AT89S51芯片介紹 ............................................... 8 主要性能特點 ....................................................... 8 AT89S51管腳說明 ................................................... 9 單片機最小系統(tǒng) ......................................................... 11 圖 最小單片機系統(tǒng) ................................................... 11 .......................................................... 11 復位電路 ......................................................... 12 溫度控制電路 設計 ....................................................... 12 ............................................................ 13 水位檢測電路設計 ....................................................... 13 穩(wěn)壓電源電路設計 ....................................................... 14 ............................................ 16 DS18B20簡介 ...................................................... 16 ...................................................... 17 ................................................................ 17 固態(tài)繼電器 SSR .................................................... 17 ...................................................... 19 .................................................. 19 4 系統(tǒng)軟件的設計 .................................................................................................................. 22 系統(tǒng)主程序 ............................................................. 22 子模塊軟件設計 ......................................................... 22 A/D轉換環(huán)節(jié)子程序設計 ............................................ 23 DS18B20溫度采集子程序設計 ........................................ 24 LCD液晶顯示子程序設計 ............................................ 25 按鍵子程序設計 .................................................... 25 總結 ....................................................................................................................................... 27 參考文獻 ................................................................................................................................ 28 致 謝 ..................................................................................................................................... 29 附錄一 ................................................................................................