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、外文原文（复印件)

Thesingle-chipmicrocomputeristheculminationofboth

thedevelopmentofthedigitalcomputerandtheintegratedcircuit

arguablythetowmostsignificantinventionsofthe20thcentury

[1].

Thesetowtypesofarchitecturearefoundinsingle—chip

microcomputer。Someemploythesplitprogram/datamemoryofthe

Harvardarchitecture,showninFig.3-5A—1，othersfollowthe

philosophy,widelyadaptedforgeneral—purposecomputersand

microprocessors,ofmakingnologicaldistinctionbetweenprogram

anddatamemoryasinthePrincetonarchitecture,showninFig。

3-5A-2.

Ingeneraltermsasingle—chipmicrocomputeris

characterizedbytheincorporationofalltheunitsofacomputer

intoasingledevice，asshowninFig3—5A—3。

memoryInput

Output

CPU

unit

DataFig.3—5A-1AHarvardtype

memory

Input

CPUOutput

memory

unit

Fig.3-5A—2.Aconventional