【正文】 of 0. 23 per t housand. ( Fal pr event ion 目 錄 摘 要 ............................................................... 目 錄 ............................................................... 第一章 緒論 .......................................................... 單片機概述 ..................................................... 信號發(fā)生器的分類 ............................................... 研究內(nèi)容 ....................................................... 第二章 方案的設計與選擇 .............................................. 方案的比較 ..................................................... 設計原理 ....................................................... 設計思想 ....................................................... 設計功能 ....................................................... 第三章 硬件設計 ...................................................... 硬件原理框圖 ................................................... 主控電路 ....................................................... 數(shù)、模轉(zhuǎn)換電路 ................................................. 按鍵接口電路 ................................................... 時鐘電路 ....................................................... 顯示電路 ....................................................... 第四章 軟件設計 ...................................................... 程序流程圖 ..................................................... 第五章 總結(jié)與展望 .................................................... 致 謝 ............................................................... 參考文獻 ............................................................. 附錄 1 電路原理圖 ..................................................... 附錄 2 源程序 ........................................................ 附錄 3 器件清單 ...................................................... 3 第一章 緒論 單片機概述 隨著大規(guī)模集成電路技術(shù)的發(fā)展，中央處理器 (CPU)、隨機存取存儲器 (RAM)、只讀存儲器 (ROM)、 (I/O)接口、定時器 /計數(shù)器和串行通信接口，以及其他一些計算機外圍電路等均可集成在一塊芯片上構(gòu)成單片微型計算機，簡稱為單片機。 classic al swine f ever im m unizat ion 123, 932, densit y of im m une 92%。s f oot and m out h disease im m une 123, 698 im m une densit y 91%。 avian inf luenza im m unizat ion 958, 626 f eather, 100% im m unization schedule, wit h t he except ion of five, t he im m unit y densit y at 100% . . Ful cover age f or wor king m ode, leaving no dead ends, 321 t echnical pr oposal, dist r ict wide open. Dist r ict, and Xiang, and ( t own) r espectively est ablished spr ing anim al epidem ic pr event ion wor k led gr oup and t echnol gy gr oup, est ablished sound anim al epidem ic pr evention account abilt y, car ef uly deploym ent, caref uly or ganizat ion, t o t ownship t echnicians, and vilage level epidem ic pr event ion m em ber and vilage gr oup cadr es posit ion im m une m ando, by vilage by households concent rat ed im m une, accor ding t o five not leak and f ive not playing of t echnology r equir em ent s im plem ent at ion anim al epidem ic pr event ion whole vilage advance wor k. Form 26 im mune over t he spr ing against m ando, Cun, pat ter ns covering 7 of t ownship ( t own), in 60 vilages, 711 vilage gr oup, pig f oot andm outh 123,698, swine f ever in im m unit y 125, 719 im m une 125, 540 t he highly pat hogenic blue ear pig disease. Scale f arm ers veter inary depar tm ent s super vise and pr ovide vaccines, im munization pr ogr ams to car ry out im munizat ion. Al f r ee r ange pigs ar e in t he aut onomous r egion wit h t he 321 t echnical solut ion t o allow an im m unizat ion, t he im m une str ess r espons e r at e is 0. 45 per t housand, and r eaction r at e of 0. 23 per thousand. ( Fall pr event ion 摘 要 本文介紹一種用 AT89C51 單片機構(gòu)成的波形發(fā)生器，可產(chǎn)生方波、三角波、正弦波、鋸齒波等多種波形，波形的周期可用程序改變，并可根據(jù)需要選擇單極性輸出或雙極性輸出，具有線路簡單、結(jié)構(gòu)緊湊、性能優(yōu)越等特點。 classical swine f ever im m unizat ion 123, 932, densit y of im m une 92%。s f oot and m out h disease im m une 123, 698 im m une densit y 91%。 no occur red eat, and took, and card, and t o of phenomenon。 one is t o car r y out t he anti cor rupt ion study, build a st r ong ideological def ense line, f urt her st udy and im plement he im pr oved st yle, close t ies wit h t he eight pr ovisions of Yunnan pr ovince, and six pr ohibit ions. Second, f ocus on pr eventing j obr elat ed cr im es war ning education, or ganize wor kers t o f ocus on wat ching t he war ning educat ion docum entar ies, or ganize cadres and wor kers t o XX pr isons involved in t he war ning educat ion。 thir d, t o est ablish a sound syst em of int ernal f inancial cont r ol. Thr ough m echanism s, activit ies t o f ur ther promote t he de Chang Xiu as Chief of st af f , Chang Si gr eed of victim s, of t en set s t he hear t int o concret e action in t he t hought r eally solve t he init iat ive t o accept super vision and const r aint pr oblem s, and consciously abide by honesty and self discipline r egulat ions. 3, seriously car ry out t hreet hree educat ion. I n t he f orm of concentr ated study and gr oup discussion, lear ning and pr acticing t he t hree thr ee pr im ar y content. Al cadr es and wor kers t o str engt hen part y spir it , belief and f ait h, enhance the m oral r ealm , t he pur suit of noble sent im ent s and consciously stay away f rom vulgar, and consciously t o bat evil. Pr act ical planning and wor k, t he ideas, policies and pr ogramm es in line wit h t he act ual sit uat ion . . . Syst em m anagement , System Manager , system managem ent m echanism, str engthen t he super vision and m anagement of cadres and wor kers, so as t o incr ease t he str engt h of honest wor k. Ser iously implement at ion Cent ral Commission f or discipline inspect ion on st rict ly ban using posit ions Shang of convenience seek not due int er ests of sever al pr ovides in t he of pr ovides。 no occur red leader s weddings dacaodaban, and part icipat ion gambling, and bus pr ivate, and bus t our ism of sit uation。 bovine