【正文】 業(yè)名 均寫全稱；成績登記表雙面打印。數(shù)字電流表把電子技術(shù)、計算技術(shù)、自動化技術(shù)的成果與精密電測量技術(shù)密切的結(jié)合在一起，成為儀器、儀表領(lǐng)域中獨(dú)立而完整的一個分支，數(shù)字電流表標(biāo)志著電子儀器領(lǐng)域的一場 革命，也開創(chuàng)了現(xiàn)代電子測量技術(shù)的先河。 關(guān)鍵詞： 單片機(jī) AT89C51 A/D 轉(zhuǎn)換 ADC0809 數(shù)據(jù)處理 ABSTRACT ABSTRACT The birth of digital voltage meter to break the traditional mode of electronic measuring instruments and patterns. It shows the clear and intuitive, accurate reading, the use of advanced digital technology, greatly reducing the human factor due to measurement errors caused by the incident. Digital voltmeter is the continuous analog (DC input voltage) into a noncontinuous, discrete digital form and displayed in the instrument. Digital voltage meter to electronic technology, puting technology, automation technology and precision electrical measurement results of the close bination of technology, as equipment, instruments and plete the field of a branch of the independent, digital voltage meter marks a revolution in the field of electronic devices Also created a precedent for modern electronic measurement technology. This design uses a microcontroller as a development platform, the control system using AT89C52 microcontroller, A / D conversion using ADC0809. System in addition to ensure the required functionality, but also can facilitate the 8 other A / D conversion volume measurement, such as extended transmission distance measurement function. Simple digital voltage measuring circuit from the A / D conversion, data processing, display control and so on. Key words: SCM AT89C51 A / D converter ADC0809 data processing 目錄 i 目 錄 第一章 引言 ................................................................................................................... 1 引言 ................................................................................................................... 1 課題研究的現(xiàn)狀和發(fā)展趨勢 ........................................................................... 1 智能儀表目前發(fā)展?fàn)顩r ................................................................................... 2 第二章 設(shè)計任務(wù)及可行性分析 ................................................................................... 5 系統(tǒng)設(shè)計要求 ................................................................................................... 5 系統(tǒng)設(shè)計思路 ................................................................................................... 5 總體結(jié)構(gòu) ........................................................................................................... 6 數(shù)字電流表的組成 ................................................................................... 6 電路設(shè)計 ................................................................................................... 6 10 倍放大器電路 .......................................................................................... 7 A/D 轉(zhuǎn)換電路 ............................................................................................... 7 電橋輸入電路 ........................................................................................... 8 測量電路 ................................................................................................... 9 第三章 元器件的選擇 ................................................................................................. 11 單片機(jī)的選擇 ................................................................................................. 11 A/D 轉(zhuǎn)換器的選擇 ......................................................................................... 12 LED 顯示電路的選擇 .................................................................................... 13 所需元器件清單 ............................................................................................. 14 第四章 數(shù)字式電流表的硬件設(shè)計 ............................................................................. 15 硬件電路設(shè)計概述 ......................................................................................... 15 主要元器件的介紹 ......................................................................................... 15 單片機(jī) AT89S51..................................................................................... 15 主要性能參數(shù) ......................................................................................... 16 AT89S51 的引腳 ......................................................................................... 16 A/D 轉(zhuǎn)換芯片 ADC0809 ........................................................................... 22 ADC0809 內(nèi)部邏輯結(jié)構(gòu) ........................................................................... 22 ii 目錄 ADC0809 的引腳 ....................................................................................... 23 ADC0809 的工作原理 ............................................................................... 24 4 位一體 7 段 LED 數(shù)碼管 ........................................................................ 24 控制電路模塊 ................................................................................................. 25 總電路 ..................................................................................................... 25 AT89S51 的復(fù)位電路和時鐘電路 ............................................................. 26 A/D 轉(zhuǎn)換電路 ............................................................................................. 27 顯示電路 ................................................................................................. 28 第五章 數(shù)字式電流表的軟件設(shè)計 ............................................................................. 29 系統(tǒng)程序設(shè)計總方案 ..................................................................................... 29 系統(tǒng)子程序設(shè)計 ............................................................................................. 29 初始化程序 ............................................................................................. 29 A/D 轉(zhuǎn)換子程序 .......................