HT67F370 datasheet(84/225 Pages) HOLTEK

84 / 225 page

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Rev. 1.00

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HT67F370

TinyPowerTM A/D Flash MCU with LCD & EEPROM

HT67F370

TinyPowerTM A/D Flash MCU with LCD & EEPROM

Programming Considerations

Withintheuserprogram,oneofthefirstthingstoconsiderisportinitialisation.Afterareset,all

oftheI/Odataandportcontrolregisterswillbesethigh.ThismeansthatallI/Opinswilldefault

toaninputstate,thelevelofwhichdependsontheotherconnectedcircuitryandwhetherpull-

highselectionshavebeenchosen.Iftheportcontrolregistersarethenprogrammedtosetupsome

pinsasoutputs,theseoutputpinswillhaveaninitialhighoutputvalueunlesstheassociatedport

dataregistersarefirstprogrammed.Selectingwhichpinsareinputsandwhichareoutputscanbe

achievedbyte-widebyloadingthecorrectvaluesintotheappropriateportcontrolregisterorby

programmingindividualbitsintheportcontrolregisterusingthe"SET[m].i"and"CLR[m].i"

instructions.Notethatwhenusingthesebitcontrolinstructions,aread-modify-writeoperationtakes

place.Themicrocontrollermustfirstreadinthedataontheentireport,modifyittotherequirednew

bitvaluesandthenrewritethisdatabacktotheoutputports.

PortAhastheadditionalcapabilityofprovidingwake-upfunctions.Whenthedeviceisinthe

SLEEPorIDLEMode,variousmethodsareavailabletowakethedeviceup.Oneoftheseisahigh

tolowtransitionofanyofthePortApins.SingleormultiplepinsonPortAcanbesetuptohavethis

function.

HT67F370 Datasheet(PDF) 84 Page - Holtek Semiconductor Inc