Holtek HT66F0175 - Page 137

Rev. 1.50 136 August 28, 2017 Rev. 1.50 137 August 28, 2017
HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
HT66F0175/HT66F0185
A/D Flash MCU with EEPROM
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
TheSIMDEB1andSIMDEB0bitsdeterminethedebouncetimeoftheI
2
Cinterface.Thisuses
thesystemclocktoineffectaddadebouncetimetotheexternalclocktoreducethepossibility
ofglitchesontheclocklinecausingerroneousoperation.Thedebouncetime,ifselected,canbe
chosentobeeither2or4systemclocks.ToachievetherequiredI
2
Cdatatransferspeed,there
existsarelationshipbetweenthesystemclock,f
SYS
,andtheI
2
Cdebouncetime.ForeithertheI
2
C
StandardorFastmodeoperation,usersmusttakecareoftheselectedsystemclockfrequencyand
thecongureddebouncetimetomatchthecriterionshowninthefollowingtable.
I
2
C Debounce Time Selection I
2
C Standard Mode (100kHz) I
2
C Fast Mode (400kHz)
No Devounce f
SYS
> 2 MHz f
SYS
> 5 MHz
2 system clock debounce f
SYS
> 4 MHz f
SYS
> 10 MHz
4 system clock debounce f
SYS
> 8 MHz f
SYS
> 20 MHz
I
2
C Minimum f
SYS
Frequency
I
2
C Registers
TherearethreecontrolregistersassociatedwiththeI
2
Cbus,SIMC0,SIMC1andSIMTOC,one
slaveaddressregister,SIMA,andonedataregister,SIMD.TheSIMDregister,whichisshownin
theaboveSPIsection,isusedtostorethedatabeingtransmittedandreceivedontheI
2
Cbus.Before
themicrocontrollerwritesdatatotheI
2
Cbus,theactualdatatobetransmittedmustbeplacedinthe
SIMDregister.AfterthedataisreceivedfromtheI
2
Cbus,themicrocontrollercanreaditfromthe
SIMDregister.AnytransmissionorreceptionofdatafromtheI
2
CbusmustbemadeviatheSIMD
register.
NotethattheSIMAregisteralsohasthenameSIMC2whichisusedbytheSPIfunction.BitSIMEN
andbitsSIM2~SIM0inregisterSIMC0areusedbytheI
2
Cinterface.
Register
Name
Bit
7 6 5 4 3 2 1 0
SIMC0 SIM2 SIM1 SIM0 — SIMDEB1 SIMDEB0 SIMEN SIMICF
SIMC1 HCF HAAS HBB HTX TXAK SRW IAMWU RXAK
SIMA IICA6 IICA5 IICA4 IICA3 IICA2 IICA1 IICA0 D0
SIMD D7 D6 D5 D4 D3 D2 D1 D0
SIMTOC SIMTOEN SIMTOF SIMTOS5 SIMTOS4 SIMTOS3 SIMTOS2 SIMTOS1 SIMTOS0
I
2
C Registers List