ADDADCINC SUBSBBDEC NEGCMP MULIMUL DAADASAAAAAS ANDORXORNOTTEST SHLSHRSALSAR ROLRORRCLRCR MOVMOVSBMOVSWSTOSBSTOSWLODSBLODSWREPCLDSTD CMPSBCMPSWSCASBSCASWREPEREPNEREPZREPNZ IN OUT JMPJZJNZJSJNSJOJNOJPJNPJBJNB
Status Sign Description: 1 - Instruction Set This flag bit is 1 0 - instruction Set the value of this flag bit to 0 R - flag bit depends on the return finger of the instruction. - The value of the flag bit is uncertain (1 or 0 is possible) Instruction Operation Description Add
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Add. Algorithm: operand1 = OPERAND1 OPERAND2 EXAMPLE: MOV Al, 5; Al = 5 Add Al, -3; Al = 2 RET
CZSOPARRRRR ADC
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Add with carry. Algorithm: operand1 = OPERAND1 OPERAND2 CF EXAMPLE: STC; SET CF = 1 MOV Al, 5; Al = 5 ADC Al, 1; Al = 7 RET
CZSOPARRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR INC
REG
Memory
INCREMENT. Algorithm: Operand = Operand 1 Example: MOV Al, 4 Inc Al; Al = 5 RET
ZsoParrrr Cf - Unchanged! SUB
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Subtract. Algorithm: Operand1 = OPERAND1 - OPERAND2 EXAMPLE: MOV AL, 5 SUB Al, 1; Al = 4 RET
CzsoParrrrrr SBB
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Subtract with borrow. Algorithm: Operand1 = OPERAND1 - OPERAND2 - CF EXAMPLE: STC MOV Al, 5 SBB AL, 3; Al = 5 - 3 - 1 = 1 Ret
CZSOPARRRRRR DEC
REG
Memory
Decrement. Algorithm: Operand = OPERAND - 1 Example: MOV Al, 255; Al = 0FFH (255 OR-1) DEC Al; Al = 0FEH (254 OR-2) RET
ZsoParrrr Cf - Unchanged! NEG
REG
Memory
NEGATE. MAKES OPERAND NEGATIVE (Two's Complement). Algorithm:
Invert All Bits of the Operandd 1 To Inverted Operand Example: MOV Al, 5; Al = 05H NEG AL; Al = 0FBH (-5) NEG Al; Al = 05H (5) Retczsoparrrrr CMP
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Compare. Algorithm: Operand1 - Operand2 Result Is Not Stored Anywhere, Flags Are Set (Of, SF, ZF, AF, PF, CF) According to Result. EXAMPLE: MOV Al, 5 MOV BL, 5 CMP AL, BL; Al = 5, zf = 1 (so equal!) RET
CZSOPARRRRR MUL
REG
Memory
Unsigned Multiply. Algorithm:
When Operand Is A
BYTE:
AX = Al * Operand.
When Operand is a word:
(DX AX) = ax * operand.
Example: MOV Al, 200; Al = 0C8H MOV BL, 4 MUL BL; AX = 0320H (800) RET
CZSOPAR ?? r ?? cf = of the result is zero. Imul
REG
Memory
Signed Multiply. Algorithm:
When Operand is a byte:
AX = Al * Operand.
When Operand is a word:
(DX AX) = ax * operand.
EXAMPLE: MOV Al, -2 MOV BL, -4 Imul BL; AX = 8 RET
CZSOPAr ?? r ?? CF = OF = 0 when result fits into operand of IMUL DAA No operands Decimal adjust After Addition Corrects the result of addition of two packed BCD values Algorithm:... If low nibble of AL> 9 or AF = 1 THEN:
Al = Al 6AF = 1 if Al> 9fh or cf = 1 THEN:
Al = Al 60HCF = 1 EXAMPLE: MOV Al, 0FH; Al = 0FH (15) DAA; Al = 15h RET
CZSOPARRRRR DAS No Operands Decimal Adjust After Subtraction of Two Packed BCD Values. Algorithm: if Low Nibble of Al> 9 OR AF = 1 THEN:
Al = Al - 6AF = 1 IF al> 9fh or cf = 1 THEN:
Al = Al - 60HCF = 1 Example: MOV Al, 0FFH; Al = 0FFH (-1) DAS; Al = 99H, CF = 1 Retczsoparrrrr AAA No Operands ASCII Adjust After Addition. CORRECTS RESULT IN AH AND Al After ADDITION WHEN WORKING WITH BCD VALUES. It works According to the Following Algorithm: if Low Nibble of Al> 9 OR AF = 1 THEN:
Al = Al 6ah = AH 1AF = 1cf = 1 else
AF = 0cf = 0 in Both Case: Cairs the high Nibble of Al. EXAMPLE: MOV AX, 15; AH = 00, Al = 0FH AAA; AH = 01, Al = 05 RET
CZSOPAR ???? R AAS No Operands ASCII Adjust After Subtraction. CORRECTS RESULT IN AH AND Al After Subtraction WHEN WORKING WITH BCD VALUES. Algorithm: if Low Nibble of Al> 9 OR AF = 1 Then:
Al = Al - 6ah = ah - 1AF = 1cf = 1 else
AF = 0cf = 0 in Both Case: Cases: Cairs the High Nibble of Al. EXAMPLE: MOV AX, 02FFH; AH = 02, Al = 0FFH AAS; AH = 01, Al = 09 RET
CZSOPAR ???? r and
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Logical and Between All Bits of Two Operands. Result is Stored IN OPERAND1. THESE RULES APPLY: 1 and 1 = 1 1 and 0 = 0 0 and 1 = 0 0 = 0 Example: MOV Al, 'A'; Al = 01100001B and Al, 1101111B; Al = 01000001B ('a') RET
CZSOP0RR0R OR OR
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Logical or Between All Bits of Two Operands. Result is Stored In First Operand. Thase Rules Apply: 1 OR 1 = 1 1 OR 0 = 0 OR 1 = 1 0 OR 0 = 0 Example: MOV Al, 'A'; Al = 01000001B or Al, 00100000B; Al = 01100001B ('a') RET
CZSOPA0R0R? Xor
REG, MEMORY
Memory, Regreg, REG
Memory, Immediate
REG, IMMEDIATE
Logical XOR (Exclusive OR) Between All Bits of Two Operands. Result is Stored In First Operand. Thase Rules Apply: 1 xor 1 = 0 1 xor 0 = 1 0 xor 1 = 1 0 xor 0 = 0 Example: MOV Al, 00000111B XOR Al, 00000010B; Al = 00000101B RET
CZSOPA0RR0R? NOT
REG
Memory
Invert Each Bit of the Operand. Algorithm:
If Bit IS 1 Turn It TO 0. If Bit IS 0 Turn It TO 1. EXAMPLE: MOV Al, 00011011B Not Al; Al = 11100100B Ret
CZSOPAunchanged Test
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
Logical and Between All Bits Of Two Operands for Flags ONLY. THESE FLAGS Are Effected: ZF, SF, PF. Result IS NOT Stored Anywhere. These Rules Apply: 1 and 1 = 1 1 and 0 = 0 0 and 1 = 0 0 0 = 0 EXAMPLE: MOV Al, 00000101B Test Al, 1; ZF = 0. Test Al, 10B; ZF = 1. Ret
CZSOP0RR0R SHL
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Shift Operand1 Left. The number of shifts is set by operand2. Algorithm:
SHIFT All Bits LEFT, The Bit That Goes Off Is TO CF.ZERO BIT IS ISERTED TO CF.ZERO BIT POSITION. EXAMPLE: MOV AL, 11100000B SHL Al, 1; Al = 11000000B, CF = 1. RET
Corr of = 0 if first Operand Keeps Original Sign. SHR
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Shift Operand1 Right. The number of shifts is set by operand2. Algorithm:
Shift All Bits Right, The Bit That Goes OFF ISET TO CF.ZERO BIT IS ISERTED to CF. izero bit is inserted to the left-most position. EXAMPLE: MOV Al, 00000111B SHR Al, 1; Al = 00000011B, CF = 1. RET
Corr of = 0 if first Operand Keeps Original Sign. Sal
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Shift Arithmetic operand1 Left The number of shifts is set by operand2 Algorithm: Shift all bits left, the bit that goes off is set to CF.Zero bit is inserted to the right-most position Example:... MOV AL, 0E0h; AL = 11100000B Sal Al, 1; Al = 11000000B, CF = 1. Ret
Corr of = 0 if First Operand Keeps Original Sign. SAR
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Shift Arithmetic Operand1 Right. The number of shifts is set by operand2. Algorithm:
SHIFT All Bits Right, The Bit That Bit That IS ISERTED TO CF.THE SIGN BIT THAT THAT THATED. EXAMPLE: MOV Al, 0E0H; Al = 11100000B SAR AL, 1 Al = 11110000B, CF = 0. MOV BL, 4CH; BL = 01001100B SAR BL, 1; BL = 00100110B, CF = 0. RET
Corr of = 0 if first Operand Keeps Original Sign. ROL
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Rotate Operand1 Left. The number of rotates is set by operand2. Algorithm:
SHIFT All Bits Left, The Bit That Goes Off Is Insert To The Right-Most Position.
EXAMPLE: MOV Al, 1CH; Al = 00011100B ROL Al, 1; Al = 00111000B, CF = 0. Ret
Corr of = 0 if First Operand Keeps Original Sign. ROR
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Rotate Operand1 Right. The number of rotates is set by operand2. Algorithm:
Shift All Bits Right, The Bit That Goes Off Is Insert To The Left-Most Position.
EXAMPLE: MOV Al, 1CH; Al = 00011100B ROR Al, 1; Al = 00001110B, CF = 0. RET
Corr of = 0 if first Operand Keeps Original Sign. RCL
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Rotate operand1 left through Carry Flag. The number of rotates is set by operand2. When immediate is greater then 1, assembler generates several RCL xx, 1 instructions because 8086 has machine code only for this instruction (the same principle works for all other shift / Rotate Instructions. Algorithm: Shift All Bits Left, The Bit That Goes Off Is Set To Cf and Previous Value of Cf Is Inserted to The Right-Most Position.
EXAMPLE: STC; SET Carry (CF = 1). MOV Al, 1CH; Al = 00011100B RCL Al, 1; Al = 00111001B, CF = 0. RET
Corr of = 0 if first Operand Keeps Original Sign. RCR
Memory, Immediate
REG, IMMEDIATE
Memory, Cl
REG, CL
Rotate Operand1 Right Through Carry Flag. The number of rotates is set by operand2. Algorithm:
Shift All Bits Right, The Bit That Goes Off Is Set To Cf and Previous Value of Cf is inserted to The Left-Most Position.
EXAMPLE: STC; SET Carry (CF = 1). MOV Al, 1CH; Al = 00011100B RCR Al, 1; Al = 10001110B, CF = 0. Ret
Corr of = 0 if first Operand Keeps Original Sign. MOV
REG, MEMORY
Memory, REG
REG, REG
Memory, Immediate
REG, IMMEDIATE
SREG, MEMORY
Memory, SREG
REG, SREG
SREG, REG
Copy Operand2 to Operand1. The Mov Instruction Cannot:
. Set the value of the CS and IP registers.copy value of one segment register to another segment register (should copy to general register first) .copy immediate value to segment register (should copy to general register first) Algorithm:
OPERAND1 = OPERAND2
Example: # Make_com # ORG 100H MOV AX, 0B800H; SET AX = B800H (VGA Memory). MOV DS, AX; Copy Value of Ax To DS. MOV CL, 'A'; CL = 41H (ASCII CODE). MOV Ch , 01011111b; CL = color attribute. MOV BX, 15EH; bx = position on screen. MOV [BX], CX; W. [0B800H: 015EH] = CX. Ret; returns to operation system.czsopaunchanged Movsb No Operands Copy Byte AtTe DS: [Si] To Es: [di]. Update Si and Di. Algorithm:
ES: [DI] = DS: [Si] IF DF = 0 THEN
Si = Si 1Di = DI 1 ELSE
Si = Si - 1Di = di - 1 Example: # Make_com # ORG 100H Lea Si, A1 Lea Di, A2 MOV CX, 5 Rep Movsb Ret A1 DB 1, 2, 3, 4, 5 A2 DB 5 DUP (0)
CZSOPAunchanged Movsw No Operands Copy Word At DS: [Si] To Es: [Di]. Update Si and Di. Algorithm:
ES: [DI] = DS: [Si] IF DF = 0 THEN
Si = Si 2DI = DI 2 ELSE
Si = Si - 2di = di - 2 example: # make_com # org 100h Lea Si, A1 Lea Di, A2 MOV CX, 5 Rep Movsw Ret A1 DW 1, 2, 3, 4, 5 A2 DW 5 DUP (0)
CzsoPaunchanged Stosb No Operands Store Byte in Al Into ES: [DI]. Update Si. Algorithm:
ES: [di] = al if DF = 0 THEN
Di = DI 1 ELSE
Di = DI - 1 Example: # Make_com # ORG 100H Lea Di, A1 MOV Al, 12H MOV CX, 5 Rep Stosb Ret A1 DB 5 DUP (0)
CZSopaunchanged Stosw No Operands Store Word In Ax Into ES: [DI]. Update Si. Algorithm:
ES: [DI] = AX if DF = 0 THEN
Di = DI 2 ELSE
Di = DI - 2 Example: # Make_com # ORG 100H Lea Di, A1 MOV AX, 1234H MOV CX, 5 Rep Stosw Ret A1 DW 5 DUP (0)
CZSOPAunchanged Lodsb No Operands Load Byte At DS: [Si] INTO Al. Update Si. Algorithm:
Al = DS: [Si] IF DF = 0 THEN
Si = Si 1 ELSE
Si = Si - 1 Example: # Make_com # ORG 100H Lea Si, A1 MOV CX, 5 MOV AH, 0EH M: LODSB INT 10H LOOP M RET A1 DB 'H', 'E', 'L', 'L', 'O'czsoPaunchanged Lodsw No Operands Load Word AT DS: [Si] INTO AX. Update Si. Algorithm:
AX = DS: [Si] IF DF = 0 THEN
Si = Si 2 ELSE
Si = Si - 2 EXAMPLE: # Make_com # ORG 100H Lea Si, A1 MOV CX, 5 Rep Lodsw; Finally There Will BE 555H in Ax. Ret A1 DW 111H, 222H, 333H, 444H, 555H
CZSOPAunchanged Rep
Chain Instruction
REPEAT FOLLOWING MOVSB, MOVSW, LODSB, LODSW, Stosb, Stosw instructions cx Times. Algorithm: Check_CX: IF CX <> 0 THEN
Do Following Chain Instructioncx = CX - 1GO Back to Check_CX Else
EXIT from rep Cycle
ZR CLD No Operands Clear Direction Flag. Si and Di Will Be Increment by Chain Instructions: Cmpsb, Cmpsw, Lodsb, Lodsw, Movsb, Movsw, Stosb, Stosw. Algorithm: DF = 0
D0 Std No Operands Set Direction Flag. Si and Di Will Be Decrement by Chain Instructions: CMPSB, Cmpsw, Lodsb, Lodsw, Movsb, Movsw, Stosb, Stosw. Algorithm: DF = 1
D1 Cmpsb No Operands Compare Bytes:
ES: [DI] from DS: [Si].
Algorithm:
DS: [Si] - ES: [DI] Set Flags According To Result: of, SF, ZF, AF, PF, CF IF DF = 0 THEN
Si = Si 1Di = DI 1 ELSE
Si = Si - 1Di = di - 1 Example: See Cmpsb.asm in Samples.
CZSOPARRRRR CMPSW No Operands Compare Words:
ES: [DI] from DS: [Si].
Algorithm:
DS: [Si] - ES: [DI] Set Flags According To Result: of, SF, ZF, AF, PF, CF IF DF = 0 THEN
Si = Si 2DI = DI 2 ELSE
Si = Si - 2di = di - 2 Example: See cmpsw.asm in samples.
CZSOPARRRRR SCASB No Operands Compare Bytes:
Al from ES: [Di] .algorithm:
ES: [DI] - Al Set Flags According To Result: of, SF, ZF, AF, PF, CF IF DF = 0 THEN
Di = DI 1 ELSE
Di = di - 1
CZSOPARRRRR SCASW No Operands Compare Words:
Ax from ES: [DI].
Algorithm:
ES: [DI] - AX Set Flags According To Result: of, SF, ZF, AF, PF, CF IF DF = 0 THEN
Di = DI 2 ELSE
Di = di - 2
CZSOPARRRRR REPE
Chain Instruction
REPEAT FOLLOWING CMPSB, CMPSW, ScaSB, Scasw ISTRUCTIONS WHILAL, MAXIMUM CX TIMES. Algorithm: Check_cx: IF CX <> 0 THEN
Do Following Chain Instructioncx = CX - 1IF ZF = 1 THEN:
Go Back to Check_CX ELSE
EXIT from REPE CYCLE ELSE
EXIT from REPE CYCLE EXAMPLE: See Cmpsb.asm in Samples.
Zr repne
Chain Instruction
REPEAT FOLLOWING CMPSB, CMPSW, SCASB, Scasw instructions while zf = 0 (Result is not equals, maximum cx Times. Algorithm: Check_cx: IF CX <> 0 THEN
Do Following Chain Instructioncx = CX - 1IF ZF = 0 THEN:
Go Back to Check_CX ELSE
EXIT from Repne Cycle Else
Exit from repne Cycle
ZR REPZ
Chain Instruction
REPEAT FOLLOWING CMPSB, CMPSW, SCASB, Scasw instructions while zf = 1 (Result is Zero), Maximum CX Times. Algorithm: Check_Cx: IF CX <> 0 THEN
Do Following Chain Instructioncx = CX - 1IF ZF = 1 THEN:
Go Back to Check_CX ELSE
Exit from repz Cycle Else
Exit from repz Cycle
Zr repnz
Chain Instruction
REPEAT FOLLOWING CMPSB, CMPSW, SCASB, Scasw instructions while zf = 0 (Result is not zero), Maximum CX Times. Algorithm: Check_CX: IF CX <> 0 THEN
Do Following Chain Instructioncx = CX - 1IF ZF = 0 THEN:
Go Back to Check_CX ELSE
EXIT from RepNZ Cycle Else
EXIT from RepNZ Cyclezr in
Al, Im.byte
Al, DX
AX, Im.byte
AX, DX
Input from port INTO Al OR AX. Second operand is a port number over 505 - dx register surplend. EXAMPLE: IN AX, 4; Get Status of Traffic Lights. In Al, 7; Get Status Of Stepper-Motor.
CzsoPaunchanged Out
Im.byte, al
Im.byte, AX
DX, Al
DX, AX
Output from al or ax number. If Required to access port number over 255 - dx register shouth. EXAMPLE: MOV AX, 0FFFH; Turn ON All Out 4, Ax; Traffic Lights. Mov Al , 100b; Turn on The Third OUT 7, Al; Magnet of The Stepper-Motor.
CZSOPAunchanged JMP
label
4-byte address
Unconditional Jump. Transfers Control to Another Part of the Program. 4-Byte Address May Be Entered In this form: 1234H: 5678H, First Value Is A Segment Second Value is an offset. Algorithm:
Always Jump
EXAMPLE: INCLUDE 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 5 JMP Label1; Jump Over 2 Lines! Print 'Not Jumped!' MOV Al, 0 Label1: Print 'Got Here!' Ret
CZSOPAunchanged JZ
label
SHORT JUMP IF ZERO (Equal). Set by CMP, SUB, ADD, TEST, AND, OR, XOR INSTRUCTIONS. Algorithm:
IF zf = 1 THEN JUMP
Example: include 'emu8086.inc' # Make_com # ORG 100H MOV Al, 5 CMP AL, 5 JZ Label1 Print 'Al Is Not Equal to 5.' JMP Equal to 5. 'EXIT: RET
CzsoPaunchanged JNZ
label
SHORT JUMP IF NOT ZERO (NOT Equal). Set by CMP, Sub, Add, Test, And, OR, XOR Instructions. Algorithm:
IF zf = 0 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 00000111b; Al = 7 OR Al, 0; Just Set Flags. JNZ Label1 Print 'Zero.' JMP EXIT Label1: Print 'Not Zero.' EXIT: RETCZSOPAUNCHANGED JS
label
Short Jump if Signed (if NEGATIVE). Set by CMP, SUB, Add, Test, And, OR, XOR Instructions. Algorithm:
IF sf = 1 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # MAKE_COM # ORG 100H MOV Al, 10000000B; Al = -128 OR Al, 0; Just Set Flags. JS Label1 Print 'Not Signed.' JMP EXIT Label1: Print 'Signed.' Exit: RET
CZSOPAunchanged JNS
label
Short jump if not sign (if posight). Set by CMP, SUB, Add, Test, And, OR, XOR Instructions. Algorithm:
IF sf = 0 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 00000111b; Al = 7 OR Al, 0; Just Set Flags. JNS Label1 Print 'Signed.' JMP EXIT Label1: Print 'Not Signed.' EXIT: RET
CZSOPAunchanged Jo
label
Short jump if overflow. Algorithm:
IF of = 1 THEN JUMP
Example:; -5 - 127 = -132 (not in -128..127); The Result of Sub is WRONG (124),; SO of = 1 is set: include 'EMU8086.Inc' # Make_com # org 100h MOV Al, -5 SUB Al, 127; Al = 7CH (124) JO Label1 Print 'No overflow.' JMP EXIT Label1: Print 'overflow!' EXIT: RET
CzsoPaunchanged JNO
label
Short jump if not overflow. Algorithm:
IF of = 0 THEN JUMP
EXAMPLE:; -5 - 2 = -7 (Inside -128..127); The result of sub is is correct,; so of = 0: include 'emu8086.inc' # make_com # org 100h MOV Al, -5 SUB Al , 2; Al = 0F9H (-7) JNO Label1 Print 'overflow!' JMP EXIT Label1: Print 'No overflow.' EXIT: RET
CZSOPAunchanged JP
Labelshort Jump if Parity (Even). Only 8 Low Bits of Result Are Checked. Set by Cmp, Sub, Add, Test, And, OR, XOR INSTRUCTIONS. Algorithm:
IF pf = 1 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # MAKE_COM # ORG 100H MOV Al, 00000101B; Al = 5 or Al, 0; Just Set Flags. JP Label1 Print 'Parity ODD.' JMP EXIT Label1: Print 'Parity Even.' Exit: RET
CZSOPAunchanged JNP
label
SHORT JUMP IF NO PARITY (ODD). Only 8 Low Bits of Result Are Cmp, Sub, Add, Test, And, OR, XOR INSTRUCTIONS. Algorithm:
IF pf = 0 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 00000111b; Al = 7 OR Al, 0; Just Set Flags. JNP Label1 Print 'Parity Even.' JMP EXIT Label1: Print 'Parity Odd.' Exit: RET
CZSOPAunchanged JB
label
SHORT JUMP if First Operand is Below Second Operand (as set by cmp instruction). Unsigned. Algorithm:
IF cf = 1 THEN JUMP
EXAMPLE: INCLUDE 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 1 CMP Al, 5 JB Label1 Print 'Al Is Not Below 5' JMP EXIT Label1: Print 'Al Is Below 5' EXIT: RET
CZSOPAunchanged JNB
label
SHORT JUMP if First Operand is Not Below Second Operand (As Set by Cmp Instruction). Unsigned. Algorithm:
IF cf = 0 THEN JUMP
Example: include 'EMU8086.INC' # Make_com # ORG 100H MOV Al, 7 CMP Al, 5 JNB Label1 Print 'Al <5.' JMP EXIT Label1: Print 'Al> = 5.' EXIT: RET
CzsoPaunchanged
