【正文】 tion. The role of water level controller can be set in accordance with the requirements of people to automatically start and shut down the motor to control the water level,When the water level reaches the set value, the motor automatically stops on water level meter, conducive to meet the growing demand for the science and technology applied to the water level control.This topic is in the simple, accurate capacitive sensor, through the 555 NE555P oscillator will water level elevation information into square wave frequency changes, after filter input single chip puter 80 C51, the monolithic integrated circuit to the frequency of the capture and count realize water level elevation detection. Through the SCM analysis, collected signal processing, drive LCD monitor LCD1602 show water level elevation, and at the same time through motor drive chip L298, control of water level to realize the small pump maintenance balance, that is, when the warning level higher than small water pump automatic drain, below the warning level automatic water pump when small, realize the automatic level of testing and maintenance function. Through the test can to below or above the warning level automatic smoke when the function of the drainage. And after many tests average results and the practical level small errors, temperature humidity changes in the environment of the test results can still meet the requirements. Finally, the realization of the system of the digital water meter and the results of the validation are summary of the design and its further improvements are discussed.Keywords: singlechip microputer。 water level。 sensonsor 西南交通大學(xué)本科畢業(yè)設(shè)計(jì)（論文） 第 V 頁(yè)目 錄摘 要 ..............................................................................................................................IVABSTRACT...............................................................................................................................V目 錄 ....................................................................................................................................VI第 1 章 緒 論 ......................................................................................................................1 本論文的背景和意義 ..............................................................................................1 本論文的主要方法和研究進(jìn)展 ..............................................................................1 本論文的主要內(nèi)容 ..................................................................................................2第 2 章 設(shè)計(jì)方案的確定 ......................................................................................................3第 3 章 硬件設(shè)計(jì) ................................................................................................................4 單片機(jī)概述 ..............................................................................................................4 單片機(jī)選擇 ..................................................................................................4 80C51 芯片簡(jiǎn)介 ..........................................................................................4 定時(shí)/計(jì)數(shù)器 ................................................................................................7 復(fù)位電路和時(shí)鐘電路的設(shè)計(jì) ..................................................................................9 復(fù)位電路的設(shè)計(jì) ..........................................................................................9 時(shí)鐘電路的選擇 ........................................................................................10 傳感器 ....................................................................................................................11 傳感器的概述 ............................................................................................11 傳感器的原理 ............................................................................................11 傳感器的制作 ............................................................................................12 信號(hào)處理模塊 ........................................................................................................16 器件選擇 ..................................................16 信號(hào)處理電路設(shè)計(jì) ..........................................17 電源模塊 ........................................................19 控制電路 ........................................................20 工作原理 ....................................................................................................20 控制電路的設(shè)計(jì) ........................................................................................22 顯示模塊 ................................................................................................................23 液晶顯示屏概述 ............................................23 液晶顯示模塊介紹 ..........................................23 顯示電路設(shè)計(jì) ............................................................................................24第 4 章 軟件設(shè)計(jì) ................................................................................................................26 西南交通大學(xué)本科畢業(yè)設(shè)計(jì)（論文） 第 VI 頁(yè) 軟件設(shè)計(jì)概述 ........................................................................................................26 結(jié)構(gòu)及程序流程 ....................................................................................................26 程序介紹 ................................................................................................................28 控制模塊 ....................................................................................................28 顯示模塊 ....................................................................................................30第 5 章 PCB 制作與測(cè)試 .....................................................................................................32 簡(jiǎn)介 .................................................................................................................32 制作 ................................................