双语教学双语教学4.doc

《双语教学双语教学4.doc》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Ch4   The Program Design of Assembly LanguagelKeywords：机器语言（MachineLanguage）汇编语言（AssemblyLanguage）高级语言（High-Level Language） 简单程序（simpleprogram）分支程序（branchprogram）循环程序（circleorloopprogram）子程序（Subprogram）lIntroduction：The8031supportsMachineLanguage，AssemblyLanguageandHigh-Level Language

2、programming.Inthe8031assemblyprogramming，theprogramhasoftenthreekindsofforms：Simpleprogram，BranchprogramandCircleprogram.Thenwe’lltellyouhowtodesignaprogram.Togainthefulldepthcontainedineachlinesexplanation,wehighlyrecommendyourefertoeachlineanditsdescription.Line1:stackThisdefinesthe

3、stackentrypoint,allwin32programscontainaSTACK.Line2:dataAlldatadefinitionsaredefinedhereLine3:codeAllProgramcodetobeexecutedgoesbelowthisstatementLine4:START:ThislinetellsthecompilerwheretoexecutetheMAINcode.AllcodewithintheSTARTandENDSTARTlabelsisexecuted.TheprogramwillLOOPthroughthe

4、contentsuntilENDSTARTisfound.Anythingwithaproceeding:isalabel.Line5:movAX,segmsgWecallupontheasm'mov'instructiontomovthecontentsofsegmentofmsgintotheAXRegister.Movisasfollows:movdestination,sourceEg:movAX,10wouldplacethevalue10intotheAXregister.Line6:movds,AXBecausewecannotmoveimmedia

5、tedatadirectlyintotheDSandESregisters,wemustmoveourdataintothegeneralpurposeregisters,andthenfromthere,intotheDataSegmentandExtraSegments.Line7:ENDSTARTWhatIhaveleftoutabovearethelinesthatcontain;'sAlinethatcontainsa;carriesacomment.Anythingafterthe;isconsideredtobeacomment,andisignor

6、edbythecompiler.Acommenthelpsimproveprogramreadability.Hopefullythissmallexampleprogramwillhelpyouonyourwaytolearningthebasicstoassemblerprogramming.Tohelpyouonyourjourney,Iwillnowgiveyousomefuninterruptstoplaywith,thatmayhelpyoudiscovernewandexcitingthings=)InterruptsOneinterruptinwh

7、ichisfoundratherhandyis16H,whichwaitsforasinglekeypressfromthekeyboard,thefollowingcodewillpausetheprogramuntilakeyhasbeenpressed:Nearlyallinterruptswillcallupontheregistersasvariableswhentheyexecutetheirinstructions.Forinterrupt16h,wemustcleartheaxregister.Interrupt16histhestandardke

8、yboar