【正文】 liquid level measurement is widely used in industry, economy, life and other fields. This design take the water tank water supply as a model, uses in carries on the survey to the water tank fluid position signal to monitor the record. The liquid level measurement device base on MCU is widely used because of many characteristics such as high measurement accuracy, good repeatability, low power consumption and long useful time. When we study Scientific Outlook on Development thoroughly, the design of electronic aid should include the thought of sustainable development. So, beyond the liquid level measurement device based on MCU, expand the functions of realtime monitoring, data acquisition, serial munication. Through the new functions, the scientific method of the liquid level measurement could be bined with Statistical Science, be used to manage the water resources reasonable, reduce energy consumption.This thesis introduces the design process of the liquid level control system by several parts as system schema, the design of hardware circuit, the software of host puter and system software, ultimately achieved the level of realtime measurement and monitoring. Finally, the paper summarizes the problems and solutions of the design process, describes briefly the method of data processing, and leads to ideas of the further design and development.Keywords：MCU；Liquid Level Measurement；Realtime monitoring；Serial Communication安徽工程大學(xué)畢業(yè)設(shè)計(jì)（論文） III 目 錄引言 ......................................................................1第 1 章 緒論 ..............................................................2 課題背景與研究意義 ..................................................2 國內(nèi)外研究現(xiàn)狀及發(fā)展 ................................................2 本課題主要研究內(nèi)容 ..................................................3第 2 章 系統(tǒng)總體方案 ......................................................4 系統(tǒng)設(shè)計(jì)要求 ........................................................4 系統(tǒng)框圖 ............................................................4 硬件設(shè)計(jì)方案 ........................................................4 主控模塊設(shè)計(jì)方案 ................................................5 鍵盤模塊設(shè)計(jì)方案 ................................................5 顯示模塊設(shè)計(jì)方案 ................................................6 數(shù)據(jù)存儲模塊設(shè)計(jì)方案 ............................................6 時(shí)間模塊設(shè)計(jì)方案 ................................................7 A/D 轉(zhuǎn)換模塊設(shè)計(jì)方案 ............................................8 通信模塊設(shè)計(jì)方案 ................................................9 電機(jī)控制模塊設(shè)計(jì)方案 ...........................................10第 3 章 硬件電路設(shè)計(jì) .....................................................11 AT89S52 硬件設(shè)計(jì) ...................................................11 按鍵設(shè)計(jì) ...........................................................13 顯示單元硬件設(shè)計(jì) ...................................................14 存儲單元硬件設(shè)計(jì) ...................................................15 時(shí)間單元硬件設(shè)計(jì) ...................................................17 A/D 轉(zhuǎn)換單元硬件設(shè)計(jì) ...............................................18 通信單元硬件設(shè)計(jì) ...................................................19 其他外圍電路的設(shè)計(jì) .................................................20第 4 章 系統(tǒng)軟件設(shè)計(jì) .....................................................22 系統(tǒng)軟件 ...........................................................22 系統(tǒng)軟件編譯開發(fā)環(huán)境 ...........................................22 系統(tǒng)主程序流程圖 ...............................................22 系統(tǒng)初始化 .....................................................22 顯示與 A/D 轉(zhuǎn)換的數(shù)據(jù)處理 .......................................24 按鍵部分軟件設(shè)計(jì) ...............................................25 顯示模塊的軟件設(shè)計(jì) .............................................26 A/D 轉(zhuǎn)換模塊軟件設(shè)計(jì) ...........................................26 電機(jī)控制模塊軟件設(shè)計(jì) ...........................................26 通信協(xié)議及通信模塊軟件設(shè)計(jì) .....................................27 時(shí)間模塊軟件設(shè)計(jì) ..............................................29 上位機(jī)軟件設(shè)計(jì) .....................................................30 上位機(jī)軟件開發(fā)編譯環(huán)境 .........................................30金小龍：基于單片機(jī)的液位控制系統(tǒng)的設(shè)計(jì) IV 上位機(jī)軟件的界面設(shè)計(jì) ...........................................31 上位機(jī)串口通信功能的實(shí)現(xiàn) .......................................32 上位機(jī)軟件中的數(shù)據(jù)處理 .........................................34結(jié)論與展望 ...............................................................35致謝 .....................................................................37參考文獻(xiàn) .................................................................38附錄 A 系統(tǒng)電路原理圖 ....................................................39附錄 B 外文文獻(xiàn)及譯文 ....................................................40附錄 C 主要參考文獻(xiàn)的題錄及摘要 ..........................................49附錄 D 系統(tǒng)軟件源代碼 ....................................................52安徽工程大學(xué)畢業(yè)設(shè)計(jì)（論文） V 插圖清單圖 21 系統(tǒng)總體框圖……………………………………………………………………… 1圖 31 AT89S52 引腳及網(wǎng)絡(luò)標(biāo)號………………………………………………………… 11圖 32 復(fù)位電路及時(shí)鐘電路………………………………………………………………13圖 33 系統(tǒng)按鍵電路………………………………………………………………………14圖 34 74LS273 及 74LS47 引腳圖 ……………………………………………………… 14圖 35 顯示部分電路圖……………………………………………………………………15圖 36 62256 引腳圖……………………………………………………………………… 16圖 37 存儲的單元電路……………………………………………………………………16圖 38 DS1302 引腳圖………………………………………………………………………17圖 39 時(shí)間單元電路………………………………………………………………………17圖 310 ADC0804 引腳圖……………………………………………………………………18圖 311 A/D 轉(zhuǎn)換單元電路圖………………………………………………………………19圖 312 MAX485 引腳圖…………………………………………………………………… 19圖 313 串行通信模塊電路圖…………………………………………………………… 20圖 314 繼電器部分電路圖……………………………………………………………… 20圖 315 電源指示燈電路圖……………………………………………………………… 21圖 41 主程序流程圖………………………………………………………………………23圖 42 鍵盤程序流程圖……………………………………………………………………25圖 43 液位檢測流程圖……………………………………………………………………27圖 44 通信檢測流程圖……………………………………………………………………28圖 45 上位機(jī)軟件界面效果圖……………………………………………………………33圖 46 水箱液位控制結(jié)構(gòu)圖………………………………………………………………33圖 51 MATLAB 繪制圖形……………………………………………………………………36金小龍：基于單片機(jī)的液位控制系統(tǒng)的設(shè)計(jì) VI 表格清單表 31 端口引腳第二功能…………………………………………………………………12表 4