计算机之父确立现代计算机结构的著名论文《First Draft of a Report on the EDVAC》。提出计算机由运算器、控制器、存储器、输入、输出设备五部分构成。存储程序原理。采用2进制。不过只有英文版。不知道谁能翻译。

1.0DEFINITIONS

1.1Theconsiderationswhichfollowdealwiththestructureofaveryhighspeedautomaticdigitalcomputingsystem,andinparticularwithitslogicalcontrol.Beforegoingintospeci cdetails,somegeneralexplanatoryremarksregardingtheseconceptsmaybeappropriate.

1.2Anautomaticcomputingsystemisa(usuallyhighlycomposite)device,whichcancarryoutinstructionstoperformcalculationsofaconsiderableorderofcomplexity—e.g.tosolveanon-linearpartialdi erentialequationin2or3independentvariablesnumerically.

Theinstructionswhichgovernthisoperationmustbegiventothedeviceinabsolutelyexhaus-tivedetail.Theyincludeallnumericalinformationwhichisrequiredtosolvetheproblemunderconsideration:Initialandboundaryvaluesofthedependentvariables,valuesof xedparameters(constants),tablesof xedfunctionswhichoccurinthestatementoftheproblem.Theseinstruc-tionsmustbegiveninsomeformwhichthedevicecansense:Punchedintoasystemofpunchcardsoronteletypetape,magneticallyimpressedonsteeltapeorwire,photographicallyimpressedonmotionpicture lm,wiredintooneormore xedorexchangeableplugboards—thislistbeingbynomeansnecessarilycomplete.Alltheseproceduresrequiretheuseofsomecodetoexpressthelogicalandthealgebraicalde nitionoftheproblemunderconsideration,aswellasthenecessarynumericalmaterial(cf.above).

Oncetheseinstructionsaregiventothedevice,itmustbeabletocarrythemoutcompletelyandwithoutanyneedforfurtherintelligenthumanintervention.Attheendoftherequiredoperationsthedevicemustrecordtheresultsagaininoneoftheformsreferredtoabove.Theresultsarenumericaldata;theyareaspeci edpartofthenumericalmaterialproducedbythedeviceintheprocessofcarryingouttheinstructionsreferredtoabove.

1.3Itisworthnoting,however,thatthedevicewillingeneralproduceessentiallymorenumericalmaterial(inordertoreachtheresults)thanthe( nal)resultsmentioned.Thusonlyafractionofitsnumericaloutputwillhavetoberecordedasindicatedin1.2,theremainderwillonlycirculateintheinteriorofthedevice,andneverberecordedforhumansensing.Thispointwillreceivecloserconsiderationsubsequently,inparticularin{12.4}.

1.4Theremarksof1.2onthedesiredautomaticfunctioningofthedevicemust,ofcourse,assumethatitfunctionsfaultlessly.Malfunctioningofanydevicehas,however,alwaysa niteprobability—andforacomplicateddeviceandalongsequenceofoperationsitmaynotbepossibletokeepthisprobabilitynegligible.Anyerrormayvitiatetheentireoutputofthedevice.Fortherecognitionandcorrectionofsuchmalfunctionsintelligenthumaninterventionwillingeneralbenecessary.

However,itmaybepossibletoavoideventhesephenomenatosomeextent.Thedevicemayrecognizethemostfrequentmalfunctionsautomatically,indicatetheirpresenceandlocationbyexternallyvisiblesigns,andthenstop.Undercertainconditionsitmightevencarryoutthenecessarycorrectionautomaticallyandcontinue(cf.{3.3}).

2.0MAINSUBDIVISIONSOFTHESYSTEM

2.1Inanalyzingthefunctioningofthecontemplateddevice,certainclassi catorydistinctionssug-gestthemselvesimmediately.

2.2First:Sincethedeviceisprimarilyacomputer,itwillhavetoperformtheelementaryopera-tionsofarithmeticsmostfrequently.Theseareaddition,subtraction,multiplicationanddivision:+, ,×,÷.Itisthereforereasonablethatitshouldcontainspecializedorgansforjusttheseopera-tions.

Itmustbeobserved,however,thatwhilethisprincipleassuchisprobablysound,thespeci cwayinwhichitisrealizedrequiresclosescrutiny.Eventheabovelistofoperations:+, ,×,÷,is

,sgn,||,alsolog10,notbeyonddoubt.Itmaybeextendedtoincludesuchoperationas√

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