HT45F0084 datasheet(21/160 Pages) HOLTEK

21 / 160 page

Rev. 1.00

�0

�a�� 1�� 01�

Rev. 1.00

�1

�a�� 1�� 01�

HT45F0084

Cord-free Vacuum Cleaner ASSP Flash MCU

Look-up Table

AnylocationwithintheProgramMemorycanbedefinedasalook-uptablewhereprogrammerscan

storefixeddata.Tousethelook-uptable,thetablepointermustfirstbesetupbyplacingtheaddress

ofthelookupdatatoberetrievedinthetablepointerregister,TBLPandTBHP.Theseregisters

definethetotaladdressofthelook-uptable.

Aftersettingupthetablepointer,thetabledatacanberetrievedfromtheProgramMemoryusing

the“TABRD[m]”or“TABRDL[m]”instructions,respectively.Whentheinstructionisexecuted,

thelowerordertablebytefromtheProgramMemorywillbetransferredtotheuserdefined

DataMemoryregister[m]asspecifiedintheinstruction.Thehigherordertabledatabytefrom

theProgramMemorywillbetransferredtotheTBLHspecialregister.Anyunusedbitsinthis

transferredhigherorderbytewillbereadas“0”.

Theaccompanyingdiagramillustratestheaddressingdataflowofthelook-uptable.

Re gi st er T BL H

Us er S el ec te d

Re gi st er

Hi gh B yt eL ow B yt e

La st p age o r

TB HP R egi st er

TB LP R eg is te r

Da ta

16bi ts

Pr og ra m Me mo ry

Instruction

Table Location Bits

b10

TABRD [m]

@10

@�

TABRDL [m]

@�

Table Location

Note:b10~b0:Tablelocationbits

@7~@0:Tablepointer(TBLP)bits

@10~@8:Tablepointer(TBHP)bits

Table Program Example

Thefollowingexampleshowshowthetablepointerandtabledataisdefinedandretrievedfromthe

microcontroller.ThisexampleusesrawtabledatalocatedintheProgramMemorywhichisstored

thereusingtheORGstatement.ThevalueatthisORGstatementis“700H”whichreferstothestart

addressofthelastpagewithinthe2KwordsProgramMemoryofthedevice.Thetablepointeris

setupheretohaveaninitialvalueof“06H”.Thiswillensurethatthefirstdatareadfromthedata

tablewillbeattheProgramMemoryaddress“706H”or6locationsafterthestartofthelastpage.

Notethatthevalueforthetablepointerisreferencedtothefirstaddressofthepresentpageifthe

“TABRD[m]”instructionisbeingused.Thehighbyteofthetabledatawhichinthiscaseisequal

tozerowillbetransferredtotheTBLHregisterautomaticallywhenthe“TABRD[m]”instructionis

executed.

BecausetheTBLHregisterisaread-onlyregisterandcannotberestored,careshouldbetaken

toensureitsprotectionifboththemainroutineandInterruptServiceRoutineusetableread

instructions.Ifusingthetablereadinstructions,theInterruptServiceRoutinesmaychangethe

valueoftheTBLHandsubsequentlycauseerrorsifusedagainbythemainroutine.Asaruleitis

recommendedthatsimultaneoususeofthetablereadinstructionsshouldbeavoided.However,in

situationswheresimultaneoususecannotbeavoided,theinterruptsshouldbedisabledpriortothe

HT45F0084 Datasheet(PDF) 21 Page - Holtek Semiconductor Inc

HT45F0084 Datasheet(HTML) 21 Page - Holtek Semiconductor Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL