标签: pic16c5x

PIC16C5XEPROM8位CMOS单片机……

ThisapplicationnotedescribesanLCDcontrollerimplementationusingaPIC16C55microcontroller.Thistechniqueoffersdisplaycapabilitiesforapplicationsthatrequireasmalldisplayatalowcost,togetherwiththecapabilitiesofthestandardPIC16C55microcontrol-ler.WestartbyanoverviewofLCDdevicesandtheirtheoryofoperationfollowedbysoftwareimplementa-tionissuesofthecontroller.Thesourcecodeforcon-trollingamultiplexedLCDdisplayisincludedinAppendixA.AN563UsingPIC16C5XMicrocontrollersasLCDDriversToturnanLCDsegment“on,”whichmakestheAuthor:AlLovrichsegmentturndarkoropaque,anLCDRMSvoltageMicrochipTechnologyInc.thatisgreaterthantheLCDthresholdvoltageisappliedtotheLCD.TheRMSLCDvoltageistheRMSvoltageINTRODUCTIONacrossthecapacitorCinFigure1,whichisequaltothe……

ThisapplicationnoteprovidessomeutilitymathroutinesforMicrochip’sPIC16C5XandPIC16CXXXseriesof8-bitmicrocontrollers.Thefollowingmathoutlinesareprovided:•8x8unsignedmultiply•16x16doubleprecisionmultiply•FixedPointDivision(Table3)•16x16doubleprecisionaddition•16x16doubleprecisionsubtraction•BCD(BinaryCodedDecimal)tobinaryconversionroutines•BinarytoBCDconversionroutines•BCDaddition•BCDsubtraction•SquarerootThesearewritteninnativeassemblylanguageandthelistingfilesareprovided.Theyarealsoavailableonadisk(MS-DOS).Alltheroutinesprovidedcanbecalledassubroutines.Mostoftheroutineshavetwodif-ferentversions:oneoptimizedforspeedandtheotheroptimizedforcodesize.Thecallingsequenceofeachroutineisexplainedatthebeginningofeachlistingfile.AN526PIC16C5X/PIC16CXXXMathUtilityRoutinesTABLE1:PERFORMANCESPECSAuthor:AmarPalacherlaMicrochipTechnologyInc.SpecProgramMemoryInstructionCyclesPLEASENOTE:ThisapplicationnoteusestheoldSpeedEfcient3537MicrochipMathRoutineformat.Itisintendedforref-CodeEfcient1671erencepurposesonlyandisbeingprovidedforthoseofyoustillimplementingBinaryCodedDeci-FIGURE1:FlowchartforUnsigned……