Holtek HT66F30 - Page 171

Rev. 2.50 170 June 22, 2017 Rev. 2.50 171 June 22, 2017
HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
HT66F20/HT66F30/HT66F40/HT66F50/HT66F60
HT66FU30/HT66FU40/HT66FU50/HT66FU60
A/D Flash MCU with EEPROM
ADCR0 Register
• HT66F20/HT66F30/HT66F40/HT66F50
Bit 7 6 5 4 3 2 1 0
Name START EOCB ADOFF ADRFS — ACS2
ACS1 ACS0
R/W R/W R R/W R/W — R/W R/W R/W
POR 0
1 1 0 — 0 0 0
Bit7 START:StarttheA/Dconversion
0→1→0:start
0→1:ResettheA/DconverterandsetEOCBto“1”
ThisbitisusedtoinitiateanA/Dconversionprocess.Thebitisnormallylowbutifset
highandthenclearedlowagain,theA/Dconverterwillinitiateaconversionprocess.
WhenthebitissethightheA/Dconverterwillbereset.
Bit6 EOCB:EndofA/Dconversionag
0:A/Dconversionended
1:A/Dconversioninprogress
ThisreadonlyagisusedtoindicatewhenanA/Dconversionprocesshascompleted.
Whentheconversionprocessisrunningthebitwillbehigh.
Bit5 ADOFF:ADCmodulepoweron/offcontrolbit
0:ADCmodulepoweron
1:ADCmodulepoweroff
ThisbitcontrolsthepowertotheA/Dinternalfunction.Thisbitshouldbecleared
tozerotoenabletheA/Dconverter.IfthebitissethighthentheA/Dconverterwill
beswitchedoffreducingthedevicepowerconsumption.AstheA/Dconverterwill
consumealimitedamountofpower,evenwhennotexecutingaconversion,thismay
beanimportantconsiderationinpowersensitivebatterypoweredapplications.
Note:1.itisrecommendedtosetADOFF=1beforeenteringIDLE/SLEEPModefor
savingpower.
2.ADOFF=1willpowerdowntheADCmodule.
Bit4 ADRFS:ADCDataFormatControl
0:ADCDataMSBisADRHbit7,LSBisADRLbit4
1:ADCDataMSBisADRHbit3,LSBisADRLbit0
Thisbitcontrolstheformatofthe12-bitconvertedA/DvalueinthetwoA/Ddata
registers.DetailsareprovidedintheA/Ddataregistersection.
Bit3 Unimplemented,readas“0”
Bit2~0 ACS2, ACS1, ACS0:SelectA/Dchannel(whenACS4is"0")
000:AN0
001:AN1
010:AN2
011:AN3
100:AN4
101:AN5
110:AN6
111:AN7
ThesearetheA/Dchannelselectcontrolbits.Asthereisonlyoneinternalhardware
A/DconvertereachoftheeightA/Dinputsmustberoutedtotheinternalconverter
usingthesebits.IfbitACS4intheADCR1registerissethighthentheinternal1.25V
willberoutedtotheA/DConverter.