数制 英文 ppt.ppt

《数制 英文 ppt.ppt》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、DigitalFundamentalsTenthEditionFloydChapter2©2008PearsonEducationThepositionofeachdigitinaweightednumbersystemisassignedaweightbasedonthebaseorradixofthesystem.Theradixofdecimalnumbersisten,becauseonlytensymbols(0through9)areusedtorepresentanynumber.SummaryThecolumnweightsofdeci

2、malnumbersarepowersoftenthatincreasefromrighttoleftbeginningwith100=1:DecimalNumbers…105104103102101100.Forfractionaldecimalnumbers,thecolumnweightsarenegativepowersoftenthatdecreasefromlefttoright:102101100.10-110-210-310-4…SummaryDecimalNumbersExpressthenumber480.52asthesumofv

3、aluesofeachdigit.ExampleSolution(9x103)+(2x102)+(4x101)+(0x100)or9x1,000+2x100+4x 10+0x1Decimalnumberscanbeexpressedasthesumoftheproductsofeachdigittimesthecolumnvalueforthatdigit.Thus,thenumber9240canbeexpressedas480.52=(4x102)+(8x101)+(0x100)+(5x10-1)+(2x10-2)SummaryBinaryNumb

4、ersFordigitalsystems,thebinarynumbersystemisused.Binaryhasaradixoftwoandusesthedigits0and1torepresentquantities.Thecolumnweightsofbinarynumbersarepowersoftwothatincreasefromrighttoleftbeginningwith20=1:…252423222120.Forfractionalbinarynumbers,thecolumnweightsarenegativepowersoft

5、wothatdecreasefromlefttoright:222120.2-12-22-32-4…SummaryBinaryNumbersAbinarycountingsequencefornumbersfromzerotofifteenisshown.00000100012001030011401005010160110701118100091001101010111011121100131101141110151111DecimalNumberBinaryNumberNoticethepatternofzerosandonesineachcolu

6、mn.Digitalcountersfrequentlyhavethissamepatternofdigits:SummaryBinaryConversionsThedecimalequivalentofabinarynumbercanbedeterminedbyaddingthecolumnvaluesofallofthebitsthatare1anddiscardingallofthebitsthatare0.Convertthebinarynumber100101.01todecimal.ExampleSolutionStartbywriting

7、thecolumnweights;thenaddtheweightsthatcorrespondtoeach1inthenumber.252423222120.2-12-232168421.½¼100101.0132+4+1+¼=37¼SummaryBinaryConversionsYoucanconvertadecimalwholenumbertobinarybyreversingtheprocedure.Writethedecimalweightofeachcolumnandplace1’sinthecolumnsthatsumtothedecim

8、alnumber.Convertthedecimalnumber49tobinary.Exam