【正文】 I 摘 要 本文論述了一種基于單片機(jī)的多功能參數(shù)檢測(cè)系統(tǒng)的設(shè)計(jì)與實(shí)現(xiàn)過程。系統(tǒng)采用了單片機(jī) STC89C52為主控芯片，設(shè)計(jì)了電流電壓轉(zhuǎn)換電路，能夠?qū)F(xiàn)場(chǎng)的溫度、壓力、流量、液位等物理量所對(duì)應(yīng)的 420mA 電流信號(hào)轉(zhuǎn)換成 15V的直流電壓信號(hào)，并提供給 A/D轉(zhuǎn)換電路。根據(jù)系統(tǒng)測(cè)量的模擬量較多的特點(diǎn)，使用 ADC0809作為 A/D轉(zhuǎn)換芯片。使用 LCD1602 作為顯示器件，能夠?qū)崟r(shí)顯示采集的溫度、壓力、流量、液位等物理量。同時(shí)，系統(tǒng)還設(shè)計(jì)了參數(shù)設(shè)置與報(bào)警提示等功能電路。 論文共分三部分介紹了基于單片機(jī)的多功能參數(shù)檢測(cè) 系統(tǒng)設(shè)計(jì)過程。第一部分，主要介紹了系統(tǒng)的方案設(shè)計(jì)，明確了系統(tǒng)的功能要求，給出了系統(tǒng)方案框圖，并對(duì)部分元器件的選擇、軟硬件開發(fā)環(huán)境進(jìn)行了介紹；第二部分，主要介紹了硬件電路的設(shè)計(jì)過程，包括主要器件的介紹、與單片機(jī)接口電路設(shè)計(jì)思路敘述；第三部分，對(duì)軟件部分的設(shè)計(jì)思路做了介紹，并分別數(shù)據(jù)采集、顯示、按鍵處理等各功能部分設(shè)計(jì)過程進(jìn)行了敘述。 關(guān)鍵詞 ：?jiǎn)纹瑱C(jī)；電流電壓轉(zhuǎn)換； A/D 轉(zhuǎn)換； LCD1602；聲光報(bào)警 II Abstract This paper discusses a kind of multifunctional parameter detection system based on single chip design use the single chip microputer as the controller STC89C52 chip,using current voltage conversion circuit can change the scene of the physical quantities,such as temperature,pressure,flow,level of 420 mA current signal into 15 V voltage signal,and provide for A/D conversion to the characteristics of the measurement system that there are much more analog quantities,ADC0809 is used as A/D conversion chip,using LCD1602 as a display device,can collect realtime display of temperature,pressure,flow and liquid the same time,the system also designed the circuit for parameter setting and sound and light alarming function. This paper is divided into three part introduces multifunctional parameter detection system based on single chip first part,mainly introduced the system design,the functional requirements of system,the system block diagram is given,and the selection of some ponents,hardware and software development environments are introduced。The second part,mainly introduces the design process of hardware circuit,including the main device,single chip microputer interface circuit design ideas of narrative。The third part,the design idea of the software part is presented,and various functions such as data acquisition,display and buttons processing are discusses. Key words: Single chip microputer。 Current voltage conversion。 A/D conversion。 LCD1602。Sound and light alarm III 目 錄 緒 論 .......................................................................................................................................... 1 1 方案設(shè)計(jì) .............................................................................................................................. 2 總體框架的設(shè)計(jì) ........................................................................................................ 2 單片機(jī)開發(fā)環(huán)境的選擇 ............................................................................................ 3 電路圖繪制軟件 .............................................................................................. 3 Keil_C軟件 ...................................................................................................... 4 2 硬件電路設(shè)計(jì) ...................................................................................................................... 6 傳感器的選型 ............................................................................................................ 6 單片機(jī)最小系統(tǒng)設(shè)計(jì) ................................................................................................ 6 單片機(jī)的選型 .................................................................................................. 6 時(shí)鐘電路與復(fù)位電路 ...................................................................................... 8 單片機(jī)使用注意事項(xiàng) .................................................................................... 10 電流電壓轉(zhuǎn)換電路設(shè)計(jì) .......................................................................................... 11 模擬量采集電路設(shè)計(jì) .............................................................................................. 13 ADC0809概述 ............................................................................................... 13 ADC0809與單片機(jī)接口電路 ....................................................................... 15 顯示電路設(shè)計(jì) .......................................................................................................... 16 LCD1602引腳結(jié)構(gòu) ....................................................................................... 16 LCD1602主要技術(shù)參數(shù)及特性 ................................................................... 16 LCD1602與單片機(jī)的接口電路 ................................................................... 17 按鍵接口電路設(shè)計(jì) .................................................................................................. 17 報(bào)警電路設(shè)計(jì) .......................................................................................................... 18 串行口功能設(shè)計(jì) ...................................................................................................... 19 RS232串行接口 ........................................................................................... 19 MAX232簡(jiǎn)介 ................................................................................................ 20 3 軟件部分設(shè)計(jì) .................................................................................................................... 22 主程序工作流程 ...................................................................................................... 22 A/D轉(zhuǎn)換子程序 ...................................................................................................... 23 數(shù)字濾波及標(biāo)度變換程序設(shè)計(jì) .............................................................................. 24 IV 顯示程序設(shè)計(jì) .......................................................................................................... 25 按鍵處理程序設(shè)計(jì) .................................................................................................. 27 報(bào)警程序設(shè)計(jì) .......................................................................................................... 28 結(jié) 論 ...............................................................................................................