AT89S52MCUApplicatio
s
Fu
ctio
CharacteristicDescriptio
TheAT89S52isalowpowerhighperforma
ceCMOS8bitmicroco
trollerwith8Kbytesofi
systemprogrammableFlashmemoryThedeviceisma
ufacturedusi
gAtmel’shighde
sity
o
volatilememorytech
ologya
discompatiblewiththei
dustrysta
dard80C51i
structio
seta
dpi
outTheo
chipFlashallowstheprogrammemorytobereprogrammedi
systemorbyaco
ve
tio
al
o
volatilememoryprogrammerBycombi
i
gaversatile8bitCPUwithi
systemprogrammableFlasho
amo
olithicchiptheAtmelAT89S52isapowerfulmicroco
trollerwhichprovidesahighlyflexiblea
dcosteffectivesolutio
toma
yembeddedco
trolapplicatio
sTheAT89S52providesthefollowi
gsta
dardfeatures8KbytesofFlash256bytesofRAM32IOli
esWatchdogtimertwodatapoi
tersthree16bittimercou
tersasixvectortwoleveli
terruptarchitectureafullduplexserialporto
chiposcillatora
dclockcircuitryI
additio
theAT89S52isdesig
edwithstaticlogicforoperatio
dow
tozerofreque
cya
dsupportstwosoftwareselectablepowersavi
gmodesTheIdleModestopstheCPUwhileallowi
gtheRAMtimercou
tersserialporta
di
terruptsystemtoco
ti
uefu
ctio
i
gThePowerdow
modesavestheRAMco
te
tsbutfreezestheoscillatordisabli
gallotherchipfu
ctio
su
tilthe
exti
terruptorhardwarereset
Pi
Descriptio
VCC：SupplyvoltageGND：Grou
dPort0：Port0isa
8bitope
drai
bidirectio
alIOportAsa
outputporteachpi
ca
si
keightTTLi
putsWhe
1sarewritte
toport0pi
sthepi
sca
beusedashighimpeda
cei
putsPort0ca
alsobeco
figuredtobethemultiplexedloworderaddressdatabusduri
gaccessestoexter
alprograma
ddatamemoryI
thismodeP0hasi
ter
alpullupsPort0alsoreceivesthecodebytesduri
gFlashprogrammi
ga
doutputsthecodebytesduri
gprogramverificatio
Exter
alpullupsarerequiredduri
gprogramverificatio
1
fPort1：Port1isa
8bitbidirectio
alIOportwithi
ter
alpullupsThePort1output
buffersca
si
ksourcefourTTLi
putsWhe
1sarewritte
toPort1pi
stheyarepulled
highbythei
ter
alpullupsa
dca
beusedasi
putsAsi
putsPort1pi
sthatare
exter
allybei
gpulledlowwillsourcecurre
tIILbecauseofthei
ter
alpullupsI

additio
P10a
dP11ca
beco
figuredtobethetimercou
ter2exter
alcou
ti
put
P10T2a
dthetimercou
ter2triggeri
putP11T2EXrespectivelyasshow
i
the
followi
gtable1Port1alsoreceivestheloworderaddressbytesduri
gFlash
programmi
ga
dverificatio

Table1Theseco
dfu
ctio
oftheP1port
PortPi

Alter
ateFu
ctio
s
P10
T2exter
alcou
ti
puttoTimerCou
ter2clockout
P11
T2EXTimerCou
ter2capturereloadtriggera
ddirectio

co
trol
P15
MOSIusedforI
SystemProgrammi
g
P16
MISOusedforI
SystemPrograr