Holtek HT66F30 - In Circ�It Programming - ICP

Rev. 2.50 32 June 22, 2017 Rev. 2.50 33 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
In Circuit Programming – ICP
TheprovisionofFlashtypeProgramMemoryprovidestheuserwithameansofconvenientand
easyupgradesandmodicationstotheirprogramsonthesamedevice.
Asanadditionalconvenience,Holtekhasprovidedameansofprogrammingthemicrocontroller
in-circuitusinga5-pininterface.Thisprovidesmanufacturerswiththepossibilityofmanufacturing
theircircuitboardscompletewithaprogrammedorun-programmedmicrocontroller,andthen
programmingorupgradingtheprogramatalaterstage.Thisenablesproductmanufacturerstoeasily
keeptheirmanufacturedproductssuppliedwiththelatestprogramreleaseswithoutremovaland
re-insertionofthedevice.
MCU Programming Pins Function
PA0
Serial Data Input/Output
PA2 Serial Clock
RES Device Reset
VDD
Power Supply
VSS Ground
TheProgramMemoryandEEPROMdatamemorycanbothbeprogrammedseriallyin-circuitusing
this5-wireinterface.Dataisdownloadedanduploadedseriallyonasinglepinwithanadditional
linefortheclock.Twoadditionallinesarerequiredforthepowersupplyandonelineforthereset.
Thetechnicaldetailsregardingthein-circuitprogrammingofthedevicesarebeyondthescopeof
thisdocumentandwillbesuppliedinsupplementaryliterature.
DuringtheprogrammingprocesstheRESpinwillbeheldlowbytheprogrammerdisablingthe
normaloperationofthemicrocontroller andtakingcontrolofthePA0andPA2I/Opinsfordata
andclockprogrammingpurposes.Theusermusttheretakecaretoensurethatnootheroutputsare
connectedtothesetwopins.
*
* *
Writer_V DD
RES
DATA
CLK
Writer_V SS
To o t her C ircuit
DATA
CLK
VSS
RES
VDD
Writer C onnecto r
Sig nals
MCU Progra mmin g
Pins
Note:*mayberesistororcapacitor.Theresistanceof*mustbegreater
than1kΩorthecapacitanceof*mustbelessthan1nF.
Programmer Pin Pins
RES PB0
DATA PA0
CLK PA2
Programmer and MCU Pins