Microprocessor and InterfacesMicroprocessorandInterfaces

Logicoperations

Logical instructionsLogicalinstructions

These instructions perform logical operations onTheseinstructionsperformlogicaloperationsondatastoredinregisters,memoryandstatusflags

The logical operations areThelogicaloperationsare AND OROR XOR RotateRotate Compare ComplementComplement

AND, OR, XORAND,OR,XOR

Any 8bit data or the contents of register orAny8 bitdata,orthecontentsofregister,ormemorylocationcanlogicallyhavetheseoperations with the contents of accumulatoroperationswiththecontentsofaccumulator ANDoperationOR operation ORoperation

XORoperationTh lt i t d i l t Theresultisstoredinaccumulator

RotateRotate

Each bit in the accumulator can be shiftedEachbitintheaccumulatorcanbeshiftedeitherleftorrighttothenextposition

CompareCompare

Any 8bit data or the contents of register orAny8 bitdata,orthecontentsofregister,ormemorylocationcanbecomparedfor Equality Equality GreaterThanLess Than LessThan

withthecontentsofaccumulator. Theresultisreflectedinstatusflags.

ComplementComplement

The contents of accumulator can beThecontentsofaccumulatorcanbecomplemented

Each 0 is replaced by 1 and each 1 is replaced Each0isreplacedby1andeach1isreplacedby0

Compareregisterormemorywithlaccumulator

Opcode Operand

CMPR

M

Contentsoftheoperand(registerormemory)arecomparedwiththecontentsofaccumulatorB h dBothcontentsarepreserved

Example: CMP B or CMP MExample:CMPBorCMPM

Compareregisterormemorywithlaccumulator

The result of the comparison is shown by setting theTheresultofthecomparisonisshownbysettingtheflagsofthePSWasfollows if(A)(reg/mem):carryandzeroflagsarereset

Compare immediate with accumulatorCompareimmediatewithaccumulator

Opcode Operand

CPI 8bitdata

Thesecondbyte(8bitdata)iscomparedwiththey ( ) pcontentsoftheaccumulatorThevaluesbeingcomparedremainunchanged

Example:CPI89H

Compare immediate with accumulatorCompareimmediatewithaccumulator

The result of the comparison is shown byTheresultofthecomparisonisshownbysettingtheflagsofthePSWasfollows: if (A) < data: carry flag is set if(A) data: carry and zero flags are reset if(A)>data:carryandzeroflagsarereset

LogicalANDregisterormemorywithlaccumulator

Opcode Operand

ANAR

M

ThecontentsoftheaccumulatorarelogicallyANDedwiththecontentsoftheoperand(registerormemory),d h l i l d i h landtheresultisplacedintheaccumulator

Iftheoperandisamemorylocation,itsaddressisspecified by the contents of HL registersspecifiedbythecontentsofHLregistersS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYisreset.ACissetp

Example:ANABorANAM

LogicalANDimmediatewithlaccumulator

Opcode Operand

ANI 8bitdata

ThecontentsoftheaccumulatorarelogicallyANDedg ywiththe8bitdata(operand)andtheresultisplacedintheaccumulatorS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYisreset.ACisset

Example:ANI86H

ExclusiveORregisterormemorywithlaccumulator

Opcode Operand

XRAR

M

ThecontentsoftheaccumulatorareExclusiveORedwiththecontentsoftheoperand(registerormemory),d h l i l d i h landtheresultisplacedintheaccumulator

Iftheoperandisamemorylocation,itsaddressisspecified by the contents of HL registersspecifiedbythecontentsofHLregistersS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYandACareresetp

Example:XRABorXRAM

ExclusiveORimmediatewithlaccumulator

Opcode Operand

XRI 8bitdata

ThecontentsoftheaccumulatorareExclusiveORedwiththe8bitdata(operand)andtheresultisplacedintheaccumulatorS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYandACarereset

Example:XRI86H

LogicalORregisterormemorywithlaccumulaotr

Opcode Operand

ORAR

M

ThecontentsoftheaccumulatorarelogicallyORedwiththecontentsoftheoperand(registerormemory),d h l i l d i h landtheresultisplacedintheaccumulator

Iftheoperandisamemorylocation,itsaddressisspecified by the contents of HL registersspecifiedbythecontentsofHLregistersS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYandACareresetp

Example:ORABorORAM

LogicalORimmediatewithlaccumulator

Opcode Operand

ORI 8bitdata

ThecontentsoftheaccumulatorarelogicallyORedg ywiththe8bitdata(operand)andtheresultisplacedintheaccumulatorS,Z,Paremodifiedtoreflecttheresultoftheoperation.CYandACarereset

Example:ORI86H

Rotate accumulator leftRotateaccumulatorleftOpcode Operand

RLC none

Eachbinarybitoftheaccumulatorisrotatedleftbyy yonePositionBitD7isplacedinthepositionofD0aswellasintheCarryflagCYismodifiedaccordingtobitD7S Z P AC are not affectedS,Z,P,ACarenotaffected

Example: RLCExample:RLC

Rotate accumulator rightRotateaccumulatorrightOpcode Operand

RRC none

Eachbinarybitoftheaccumulatorisrotatedrightbyy g yonepositionBitD0isplacedinthepositionofD7aswellasintheCarryflagCYismodifiedaccordingtobitD0S Z P AC are not affectedS,Z,P,ACarenotaffected

Example: RRCExample:RRC

Rotate accumulator left through carryRotateaccumulatorleftthroughcarry

Opcode Operand

RAL none

Eachbinarybitoftheaccumulatorisrotatedleftbyy yonepositionthroughtheCarryflagBitD7isplacedintheCarryflag,andtheCarryflagisplacedintheleastsignificantpositionD0CYismodifiedaccordingtobitD7S Z P AC are not affectedS,Z,P,ACarenotaffected

Example: RALExample:RAL

Rotate accumulator right through carryRotateaccumulatorrightthroughcarry

Opcode Operand

RAR none

Eachbinarybitoftheaccumulatorisrotatedrightbyy g yonepositionthroughtheCarryflagBitD0isplacedintheCarryflag,andtheCarryflagisplacedinthemostsignificantpositionD7CYismodifiedaccordingtobitD0S Z P AC are not affectedS,Z,P,ACarenotaffected

Example: RARExample:RAR

Complement accumulatorComplementaccumulatorOpcode Operand

CMA none

ThecontentsoftheaccumulatorarecomplementedpNoflagsareaffected

Example:CMA

Complement carryComplementcarryOpcode Operand

CMC none

TheCarryflagiscomplementedy g pNootherflagsareaffected

Example:CMC

Set CarrySetCarryOpcode Operand

STC none

TheCarryflagissetto1y gNootherflagsareaffected

Example:STC