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REPZ/REPE (Repeat while zero/Repeat while equal). It is a conditional repeat instruction prefix. It behaves the same as a REP instruction provided the Zero Flag is set (i.e. ZF = 1). It is used with CMPS instruction. REPNZ/REPNE (Repeat while not zero/Repeat while not equal). It is a conditional repeat
Like the unconditional repeat prefix, there are conditional repeat prefixes that come with string instructions. REPE (Repeat if Equal) or REPZ (Repeat if ZF="1") is one of the conditional repeat prefixes that come with string instructions. Its operation is similar to the REP prefix except that repetition is also conditional on the Zero
Opcode. Instruction. Description. F3 6C. REP INS r/m8, DX. Input (E)CX bytes from port DX into ES:[(E)DI]. F3 6D. REP INS r/m16,DX. Input (E)CX words from port DX into ES:[(E)DI]. F3 6D. REP INS r/m32,DX. Input (E)CX doublewords from port DX into ES:[(E)DI]. F3 A4. REP MOVS m8,m8. Move (E)CX bytes from DS:[(E)SI]
To work on an entire string at a time, each string instruction can be accompanied by a repeat prefix, either REP or one of REPE and REPNE (or their synonyms REPZ and REPNZ). These cause the instruction to be repeated the number of times in the count register, CX; for REPE and REPNE, the Zero flag is tested at the end
REP/REPE/REPZ/REPNE/REPNZ -- Repeat Following String Operation Opcode Instruction Clocks Description F3 6C REP INS r/m8, DX 13+6*(E)CX, pm="7"+6*(E)CX If CPL <= IOPL/ 27+6*(E)CX If CPL > IOPL or if in virtual 8086 mode Input (E)CX bytes from port DX into ES:[(E)DI] F3 6D REP INS r/m16,DX 13+6*(E)CX,
REPE/REPZ causes the succeeding string instruction to be repeated as long as the comapred bytes or words are equal (ZF = 1) and CX is not yet counted down to zero. The REPNE and the Usage REPE/REPE/REPZ/REPNZ Operands, Clocks, Size in Bytes. 8086, 286, 386, 486. none, 2, 2, 2, 1, 1
REPE/REPZ - Repeat Equal / Repeat Zero Usage: REPE REPZ Modifies flags: None Repeats execution of string instructions while CX != 0 and the Zero Flag is set. CX is decremented and the Zero Flag tested after each string operation. The combination of a repeat prefix and a segment override on processors other than
8086 has a powerful set of string related instructions and are DIscussed below: REP GROUP: REPE prefix will cause string instruction to be repeated, as long as compared bytes or words are equal or CX is not zero. GenerALly used with These instructions are used with REP, REPE or REPNE prefixes. - - - - - - MOV CX
Direction Flag. one of 8086 processor control flags. controls the direction of string operations: DF = 0 => forward (left to right) processing; DF = 1 => backward (right to left) processing. CLD - clears the DF; sets DF = 0. STD - sets DF = 1
The return address to the calling program (the current value of the IP) is saved on the stack; IP get the offset address of the first instruction of the procedure (this . is found (zf = 1) or cx = 0; repnz is a synonym for repne; repe (repeat while equal) repeats a string instruction until zf = 0 or cx = 0; repz is a](http://cdn08.dayviews.com/501/_u4/_u1/_u9/_u4/_u0/_u2/u4194022/63768_1522076464/Repe_instruction_in_8086_http_tbo_cloudz_pw_download_file_repe_instruction_in_8086_Download_Repe.jpg)
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Repe instruction in 8086: >> http://tbo.cloudz.pw/download?file=repe+instruction+in+8086 << (Download)
Repe instruction in 8086: >> http://tbo.cloudz.pw/read?file=repe+instruction+in+8086 << (Read Online)
REPZ/REPE (Repeat while zero/Repeat while equal). It is a conditional repeat instruction prefix. It behaves the same as a REP instruction provided the Zero Flag is set (i.e. ZF = 1). It is used with CMPS instruction. REPNZ/REPNE (Repeat while not zero/Repeat while not equal). It is a conditional repeat
Like the unconditional repeat prefix, there are conditional repeat prefixes that come with string instructions. REPE (Repeat if Equal) or REPZ (Repeat if ZF="1") is one of the conditional repeat prefixes that come with string instructions. Its operation is similar to the REP prefix except that repetition is also conditional on the Zero
Opcode. Instruction. Description. F3 6C. REP INS r/m8, DX. Input (E)CX bytes from port DX into ES:[(E)DI]. F3 6D. REP INS r/m16,DX. Input (E)CX words from port DX into ES:[(E)DI]. F3 6D. REP INS r/m32,DX. Input (E)CX doublewords from port DX into ES:[(E)DI]. F3 A4. REP MOVS m8,m8. Move (E)CX bytes from DS:[(E)SI]
To work on an entire string at a time, each string instruction can be accompanied by a repeat prefix, either REP or one of REPE and REPNE (or their synonyms REPZ and REPNZ). These cause the instruction to be repeated the number of times in the count register, CX; for REPE and REPNE, the Zero flag is tested at the end
REP/REPE/REPZ/REPNE/REPNZ -- Repeat Following String Operation Opcode Instruction Clocks Description F3 6C REP INS r/m8, DX 13+6*(E)CX, pm="7"+6*(E)CX If CPL <= IOPL/ 27+6*(E)CX If CPL > IOPL or if in virtual 8086 mode Input (E)CX bytes from port DX into ES:[(E)DI] F3 6D REP INS r/m16,DX 13+6*(E)CX,
REPE/REPZ causes the succeeding string instruction to be repeated as long as the comapred bytes or words are equal (ZF = 1) and CX is not yet counted down to zero. The REPNE and the Usage REPE/REPE/REPZ/REPNZ <String Instruction> Operands, Clocks, Size in Bytes. 8086, 286, 386, 486. none, 2, 2, 2, 1, 1
REPE/REPZ - Repeat Equal / Repeat Zero Usage: REPE REPZ Modifies flags: None Repeats execution of string instructions while CX != 0 and the Zero Flag is set. CX is decremented and the Zero Flag tested after each string operation. The combination of a repeat prefix and a segment override on processors other than
8086 has a powerful set of string related instructions and are DIscussed below: REP GROUP: REPE prefix will cause string instruction to be repeated, as long as compared bytes or words are equal or CX is not zero. GenerALly used with These instructions are used with REP, REPE or REPNE prefixes. - - - - - - MOV CX
Direction Flag. one of 8086 processor control flags. controls the direction of string operations: DF = 0 => forward (left to right) processing; DF = 1 => backward (right to left) processing. CLD - clears the DF; sets DF = 0. STD - sets DF = 1
The return address to the calling program (the current value of the IP) is saved on the stack; IP get the offset address of the first instruction of the procedure (this . is found (zf = 1) or cx = 0; repnz is a synonym for repne; repe (repeat while equal) repeats a string instruction until zf = 0 or cx = 0; repz is a synonym for repe.
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