![• Operation Performed :--
• Destination Destination AND source
• Examples :--
1. AND BH,CL ;AND byte in CL with Byte in BH,
result in BH.
2. AND BX,00FFH ;AND word in BX with immediate
data 00ffH
3. AND [5000H], DX ;AND word in DX with a
word in memory with offset
5000 in DS.
AND (Logical AND) contd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-5-320.jpg)
![• Operation Performed :--
• Destination Destination OR source
• Examples :--
1. OR BH,CL ;OR byte in CL with Byte in BH,
result in BH.
2. OR BX,00FFH ;OR word in BX with immediate
data 00ffH
3. OR [5000H], DX ; OR word in DX with a
word in memory with offset
5000 in DS.
OR (Logical OR) contd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-8-320.jpg)
![• Operation Performed :--
• Destination Destination XOR source
• Examples :--
1. XOR BH,CL ;XOR byte in CL with Byte in BH,
result in BH.
2. XOR BX,00FFH ;XOR word in BX with immediate
data 00ffH
3. XOR [5000H], DX ; XOR word in DX with a
word in memory with offset
5000 in DS.
XOR (Logical XOR) contd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-11-320.jpg)
![• Operation Performed :--
• Destination NOT Destination
• Examples :--
1. NOT BH ;Complement byte in BH, result in BH.
2. NOT BX ; Complement word in BX, result in BX.
3. NOT BYTE PTR [5000H] ; Complement byte
in memory with offset 5000 in DS.
NOT (Logical Invert ) contd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-14-320.jpg)
![• Operation Performed :--
– Flags set result of Destination AND source
• Examples :--
1. TEST BH,CL ;AND byte in CL with Byte in BH,
no result but flags are affected.
2. TEST BX,00FFH ;AND word in BX with immediate
data 00ffH, no result but flags are
affected.
3. TEST DX, [5000H];AND word in DX with a word in
memory with offset 5000 in DS,
no result but flags are affected.
TEST (Logical Compare) contd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-17-320.jpg)
![• Example :--
• Use of SHL instruction for Multiplication:-
– If CF = 0, BH = 04H
– MOV CL, 03 ; Load CL register for
the count
– SHL BH, CL ; Shift the contents
of BX register by one
towards left
– BH = 20H (32D) [ 04 * 23 = 32 D]
– Note :-- SHL can be used to multiply a number
with powers of 2.
SHL / SAL (Shift Logical/Arithmetic Left)Cntd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-20-320.jpg)
![• Example :--
• Use of SAR instruction for Division:-
– If CF = 0, BH = 14H
– MOV CL, 02 ; Load CL register for the
count
– SAR BH, CL ; Shift the contents
of BX register by one
towards right
– BH = 05H (20D) [ 20 / 22 = 05D]
– Note :-- SAR can be used to divide a number with
powers of 2 and get the quotient.
SAR (Shift Arithmetic Right )Cntd..](https://image.slidesharecdn.com/chapter38086instlogical2-200319141120/85/Chapter3-8086inst-logical-2-24-320.jpg)
Chapter3 8086inst logical 2
- 1. Summary of Arithmetic Instructions –ADD D,S –ADC D,S –SUB D,S –SBB D,S –CMP D,S –NEG D –DAA –DAS
- 2. Summary of Arithmetic Instructions – AAA – AAS – AAM – AAD – INC D – DEC D – DIV S – IDIV S – MUL S – IMUL S – CBW – CWD
- 3. Logical Instructions –These are the instructions used for basic logic operations such as AND, OR, NOT and XOR. –These are also used for carrying out bit by bit operations such as shift (SHR,SHL) or rotate (ROL,ROR,RCR,RCL). – One more Instruction under this category is TEST instruction.
- 4. AND (Logical AND) Syntax :-- AND destination, source • This instruction is used to bit by bit AND the contents of source to the destination. •The result is stored in the destination. •The source operand can be a immediate, a register or a memory location. •The destination can be a register or a memory location, but not an immediate data. •Both operands cannot be immediate data or memory location. •Flags affected : OF = 0 ,CF = 0 , AF is undefined. • And other flags (SF, ZF, PF) are affected based on the AND operation.
- 5. • Operation Performed :-- • Destination Destination AND source • Examples :-- 1. AND BH,CL ;AND byte in CL with Byte in BH, result in BH. 2. AND BX,00FFH ;AND word in BX with immediate data 00ffH 3. AND [5000H], DX ;AND word in DX with a word in memory with offset 5000 in DS. AND (Logical AND) contd..
- 6. Numeric Example If AX = 3F0F, After Instruction, AND AX,9078H ; AX AX AND 9078H ;AX 3F0F AND 9078 3F0F 0011 1111 0000 1111 AND 9078 1001 0000 0111 1000 ------------------------------------- = 0001 0000 0000 1000 1008H in AX register
- 7. OR (Logical OR) Syntax :-- OR destination, source • This instruction is used to bit by bit OR the contents of source to the destination. •The result is stored in the destination. •The source operand can be a immediate, a register or a memory location. •The destination can be a register or a memory location, but not an immediate data. •Both operands cannot be immediate data or memory location. •Flags affected : OF = 0 ,CF = 0 , AF is undefined. • And other flags (SF, ZF, PF) are affected based on the OR operation.
- 8. • Operation Performed :-- • Destination Destination OR source • Examples :-- 1. OR BH,CL ;OR byte in CL with Byte in BH, result in BH. 2. OR BX,00FFH ;OR word in BX with immediate data 00ffH 3. OR [5000H], DX ; OR word in DX with a word in memory with offset 5000 in DS. OR (Logical OR) contd..
- 9. Numeric Example If AX = 3F0F, After Instruction, OR AX,9078H ; AX AX OR 9078H ;AX 3F0F OR 9078 3F0F 0011 1111 0000 1111 OR 9078 1001 0000 0111 1000 ------------------------------------- = 1011 1111 0111 1111 BF7FH in AX register
- 10. XOR (Logical XOR) Syntax :-- XOR destination, source • This instruction is used to bit by bit XOR the contents of source to the destination. •The result is stored in the destination. •The source operand can be a immediate, a register or a memory location. •The destination can be a register or a memory location, but not an immediate data. •Both operands cannot be immediate data or memory location. •Flags affected : OF = 0 ,CF = 0 , AF is undefined. • And other flags (SF, ZF, PF) are affected based on the XOR operation.
- 11. • Operation Performed :-- • Destination Destination XOR source • Examples :-- 1. XOR BH,CL ;XOR byte in CL with Byte in BH, result in BH. 2. XOR BX,00FFH ;XOR word in BX with immediate data 00ffH 3. XOR [5000H], DX ; XOR word in DX with a word in memory with offset 5000 in DS. XOR (Logical XOR) contd..
- 12. Numeric Example If AX = 3F0F, After Instruction, XOR AX,9078H ; AX AX XOR 9078H ;AX 3F0F XOR 9078 3F0F 0011 1111 0000 1111 XOR 9078 1001 0000 0111 1000 ------------------------------------- = 1010 1111 0111 0111 AF77H in AX register
- 13. NOT (Logical Invert ) Syntax :-- NOT destination • This instruction complements (inverts) each bit of the byte or word stored in the destination. •The result is stored in the destination. •The destination can be a register or a memory location. •No Flags affected
- 14. • Operation Performed :-- • Destination NOT Destination • Examples :-- 1. NOT BH ;Complement byte in BH, result in BH. 2. NOT BX ; Complement word in BX, result in BX. 3. NOT BYTE PTR [5000H] ; Complement byte in memory with offset 5000 in DS. NOT (Logical Invert ) contd..
- 15. Numeric Example If AX = 3F0F, After Instruction, NOT AX ; AX NOT AX ;AX NOT 3F0F 3F0F 0011 1111 0000 1111 Complement ------------------------------------- = 1100 0000 1111 0000 C0F0H in AX register
- 16. TEST (Logical compare ) Syntax :-- TEST destination, source • This instruction is used to bit by bit AND the contents of source to the destination. •The result is not stored in the destination. •The source operand can be a immediate, a register or a memory location. •The destination can be a register or a memory location, but not an immediate data. •Both operands cannot be immediate data or memory location. •Flags affected : OF = 0 ,CF = 0 , SF, ZF, PF. •TEST instruction is used to set flags before a conditional jump instruction
- 17. • Operation Performed :-- – Flags set result of Destination AND source • Examples :-- 1. TEST BH,CL ;AND byte in CL with Byte in BH, no result but flags are affected. 2. TEST BX,00FFH ;AND word in BX with immediate data 00ffH, no result but flags are affected. 3. TEST DX, [5000H];AND word in DX with a word in memory with offset 5000 in DS, no result but flags are affected. TEST (Logical Compare) contd..
- 18. SHL / SAL (Shift Logical/Arithmetic Left) Syntax :-- SHL/SAL destination, count • SHL & SAL are the opcodes for the same operation •This instruction shifts the destination bit by bit to the left and insert zeroes in the newly introduced least significant bits. •The shift operation is through carry. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF, SF, ZF, PF. •These instructions can be used to multiply an unsigned number by power of 2.
- 19. CF BX 0 0 1 CF BX • Operation Performed :-- –CF MSB ------------------ LSB 0 • Example :-- – If CF = 0, BX = E6D3H – After SAL BX, 1 ; Shift the contents of BX register by one towards left SHL / SAL (Shift Logical/Arithmetic Left)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 0 BX = CDA6
- 20. • Example :-- • Use of SHL instruction for Multiplication:- – If CF = 0, BH = 04H – MOV CL, 03 ; Load CL register for the count – SHL BH, CL ; Shift the contents of BX register by one towards left – BH = 20H (32D) [ 04 * 23 = 32 D] – Note :-- SHL can be used to multiply a number with powers of 2. SHL / SAL (Shift Logical/Arithmetic Left)Cntd..
- 21. 0 0 0 1 0 0 0 0 CF BH 0 0 0 0 0 0 0 SHL / SAL (Shift Logical/Arithmetic Left)Cntd.. BH = 20H with CF = 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0
- 22. SAR (Shift Arithmetic Right ) Syntax :-- SAR destination, count • This instruction shifts the destination bit by bit to the right and MSB position is kept in the old MSB position •The shift operation is through carry, LSB is shifted to CF. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF, SF, ZF, PF. •This instruction can be used to divide an unsigned number by power of 2.
- 23. BX CF 0 1 BX CF 1 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 • Operation Performed :-- – MSB ----------------- LSB CF • Example :-- – If CF = 0, BX = E6D3H – After SAR BX, 1 ; Shift the contents of BX register by one towards right SAR (Shift Arithmetic Right)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = F369H
- 24. • Example :-- • Use of SAR instruction for Division:- – If CF = 0, BH = 14H – MOV CL, 02 ; Load CL register for the count – SAR BH, CL ; Shift the contents of BX register by one towards right – BH = 05H (20D) [ 20 / 22 = 05D] – Note :-- SAR can be used to divide a number with powers of 2 and get the quotient. SAR (Shift Arithmetic Right )Cntd..
- 25. 0 0 0 0 0 1 0 1 BH CF 0 0 0 SAR (Shift Arithmetic Right)Cntd.. BH = 05H with CF = 0 0 0 0 1 0 1 0 0 0 0 0 0 1 0 1 0
- 26. SHR (Shift Logical Right) Syntax :-- SHR destination, count •This instruction shifts the destination bit by bit to the right and insert zeroes in the newly introduced most significant bits. •The shift operation is through carry. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF, SF, ZF, PF.
- 27. BX CF 0 0 1 BX CF 0 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 • Operation Performed :-- –0 MSB ------------------ LSB CF • Example :-- – If CF = 0, BX = E6D3H – After SHR BX, 1 ; Shift the contents of BX register by one towards right SHR (Shift Logical Right)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = 7369H
- 28. ROR (Rotate Right without Carry) Syntax :-- ROR destination, count •This instruction rotates the destination bit by bit to the right excluding the carry •The bit moved out of LSB is rotated around into the MSB and also copied to CF. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF
- 29. BX CF 0 1 BX CF 1 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 • Operation Performed :-- – MSB LSB CF • Example :-- – If CF = 0, BX = E6D3H – After ROR BX, 1 ; Rotate the contents of BX register by one towards right ROR (Rotate Right without Carry)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = F369H
- 30. • Example :-- – If CF = 0, BH = 54H – MOV CL, 02 ; Load CL register for the count ROR BH, CL ; Rotate the contents of BH register by twice towards right ROR (Rotate Right without Carry)Cntd.. 0 0 0 1 0 1 0 1 BH CF 0 0 0 0 1 0 1 0 1 0 0 0 0 1 0 1 0 1 0 BH = 15H with CF = 0
- 31. • Uses of ROR instruction:-- • This instruction can be used to swap the nibbles in a byte or to swap the bytes in a word. – MOV CL,04H ROR AL, CL • It can also be used to rotate the bit into CF which can be checked later for a conditional jump. (JC or JNC)
- 32. ROL (Rotate Left without Carry) Syntax :-- ROL destination, count •This instruction rotates the destination bit by bit to the left excluding the carry •The bit moved out of MSB is rotated around into the LSB and also copied to CF. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF
- 33. CF BX 0 1 CF BX 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 1 • Operation Performed :-- – CF MSB LSB • Example :-- – If CF = 0, BX = E6D3H – After ROL BX, 1 ; Rotate the contents of BX register by one towards left ROL (Rotate Left without Carry)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = CDA7H
- 34. • Example :-- – If CF = 0, BH = 54H – MOV CL, 02 ; Load CL register for the count ROL BH, CL ; Rotate the contents of BH register by twice towards Left ROL (Rotate Left without Carry)Cntd.. 0 1 0 1 0 0 0 1 CF BH 0 0 1 0 1 0 1 0 1 0 0 1 0 1 0 1 0 0 0 BH = 51H with CF = 1
- 35. • Uses of ROL instruction:-- • This instruction can be used to swap the nibbles in a byte or to swap the bytes in a word. – MOV CL,04H ROL AL, CL • It can also be used to rotate the bit into CF which can be checked later for a conditional jump. (JC or JNC)
- 36. RCR (Rotate Right with Carry) Syntax :-- ROR destination, count •This instruction rotates the destination bit by bit to the right including the carry •The bit moved out of LSB is rotated into CF and the bit in CF is rotated into the MSB. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF
- 37. BX CF 0 1 BX CF 0 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 • Operation Performed :-- – MSB LSB CF • Example :-- – If CF = 0, BX = E6D3H – After RCR BX, 1 ; Rotate the contents of BX register by one towards right through carry RCR (Rotate Right with Carry)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = 7369H
- 38. • Example :-- – If CF = 0, BH = 54H – MOV CL, 02 ; Load CL register for the count RCR BH, CL ; Rotate the contents of BH register by twice towards right through carry RCR (Rotate Right with Carry)Cntd.. 0 0 0 1 0 1 0 1 BH CF 0 0 0 0 1 0 1 0 1 0 0 0 0 1 0 1 0 1 0 BH = 15H with CF = 0
- 39. RCL (Rotate Left with Carry) Syntax :-- RCL destination, count •This instruction rotates the destination bit by bit to the left including the carry •The bit moved out of MSB is rotated into CF and the bit in CF is rotated into the LSB. •The count can be either 1 or specified by CL register. •The destination can be a byte or a word in register or a memory location, but not an immediate data. •Flags affected : OF ,CF
- 40. CF BX 0 1 CF BX 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 0 • Operation Performed :-- – CF MSB LSB • Example :-- – If CF = 0, BX = E6D3H – After RCL BX, 1 ; Rotate the contents of BX register by one towards left through carry RCL (Rotate Left with Carry)Cntd.. 1 1 1 0 0 1 1 0 1 1 0 1 0 0 1 1 BX = CDA6H
- 41. • Example :-- – If CF = 0, BH = 54H – MOV CL, 02 ; Load CL register for the count RCL BH, CL ; Rotate the contents of BH register by twice towards Left through carry RCL (Rotate Left with Carry)Cntd.. 0 1 0 1 0 0 0 0 CF BH 0 0 1 0 1 0 1 0 1 0 0 1 0 1 0 1 0 0 0 BH = 50H with CF = 1