【正文】 上圖為CPU原理圖。設(shè)計(jì)中采用了模數(shù)轉(zhuǎn)換器，利用AD0809型8位MOS型A/D轉(zhuǎn)換器。按1：進(jìn)入下一模式。關(guān)鍵詞：?jiǎn)纹瑱C(jī) ADC0809 A/D轉(zhuǎn)換 模塊顯示 電壓測(cè)量目　錄一 緒論.................................................................. 1...................................................... 目的、任務(wù)................................. .. 1 .............................................. ...1 .................................... ...2二 硬件電路設(shè)計(jì)............................. ............................ 2 主要芯片介紹................................................. 2 AT89S51 .................................................2 A/D0809................................................. 3 單片機(jī)電路 ...................................................4 單片機(jī)電路板............................................4 單片機(jī)最小系統(tǒng)......................................... 4 單片機(jī)的復(fù)位電路 .......................................5 開關(guān)電路 ...............................................5 顯示譯碼電路 ...........................................6 蜂鳴器和繼電器電路 .....................................7 A/D轉(zhuǎn)換 ......................................................7 ADC0809內(nèi)部結(jié)構(gòu) ........................................7 ADC0809轉(zhuǎn)換原理 ........................................8................................................8 ...............................8三 軟件設(shè)計(jì) ..............................................................9 設(shè)計(jì)任務(wù)..................................................... 9 基本任務(wù) .............................................9 擴(kuò)展任務(wù) .............................................9 程序代碼.....................................................9 C語言實(shí)現(xiàn)基本功能 ......................................9 ............................................17四 系統(tǒng)調(diào)試 .............................................................17 硬件部分 ...................................................17 軟件部分 ...................................................18五 總結(jié)..................................................................18參考文獻(xiàn)：...............................................................18附錄一 A/D轉(zhuǎn)換板原理圖 ..........