User`s guide

Rev. 1.10 92 November 14, 2014 Rev. 1.10 93 November 14, 2014
HT66FW2230
Wireless Charger A/D Flash 8-Bit MCU
I
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C Interface
TheI
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Cinterfaceisusedtocommunicatewithexternalperipheraldevicessuchassensors,
EEPROMmemoryetc.OriginallydevelopedbyPhilips,itisatwolinelowspeedserialinterface
forsynchronousserialdatatransfer.Theadvantageofonlytwolinesforcommunication,relatively
simplecommunicationprotocolandtheabilitytoaccommodatemultipledevicesonthesamebus
hasmadeitanextremelypopularinterfacetypeformanyapplications.
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I
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C Master/Slave Bus Connection
I
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C Interface Operation
TheI
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Cserialinterfaceisatwolineinterface,aserialdataline,SDA,andserialclockline,SCL.As
manydevicesmaybeconnectedtogetheronthesamebus,theiroutputsarebothopendraintypes.
Forthisreasonitisnecessarythatexternalpull-highresistorsareconnectedtotheseoutputs.Note
thatnochipselectlineexists,aseachdeviceontheI
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Cbusisidentiedbyauniqueaddresswhich
willbetransmittedandreceivedontheI
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Cbus.
WhentwodevicescommunicatewitheachotheronthebidirectionalI
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Cbus,oneisknownasthe
masterdeviceandoneastheslavedevice.Bothmasterandslavecantransmitandreceivedata,
however,itisthemasterdevicethathasoverallcontrolofthebus.Forthisdevice,whichonly
operatesinslavemode,therearetwomethodsoftransferringdataontheI
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Cbus,theslavetransmit
modeandtheslavereceivemode.
ItissuggestedthattheusershallnotenterthemicroprocessortoHALTmodebyapplication
programduringprocessingI
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Ccommunication.
IfthepinisconguredtoSDAorSCLfunctionofI
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Cinterface,thepinisconguredtoopen-collect
Input/Outputportanditspull-upfunctioncanbeenabledbyprogrammingtherelatedGenericPull-
upControlRegister.
START signal
from M aste r
Send s la ve addre ss
and R/W bit from M aste r
A cknow le dge
from s la ve
S end data byte
from M aste r
A cknow l edge
from s la ve
STOP s ig nal
from M aste r