This document provides an overview of assembly language programming on the 8086 processor. It includes examples of assembly code using MOV, MUL, and other instructions. It then summarizes various 8086 instruction types like data transfer, arithmetic, logical, and control flow instructions. For each type, it lists some common instructions and provides brief descriptions and examples.

1. University of Pune
S.E. I.T.
Subject code: 214447
Processor Architecture and
Interfacing
Part 02: Assembly Language Programming
With 8086
Tushar B Kute,
Sandip Institute of Technology
and Research Centre, Nashik
tbkute@gmail.com

2. Program Development
• Assembly Language Program Development

3. DATA SEGMENT ;Data segment declaration
MULTIPLICAND DW 341AH
MULTIPLIER DW 20F4H
PRODUCT DW 2 DUP(0)
DATA ENDS
CODE SEGMENT
ASSUME CS:CODE, DS:DATA
START: MOV AX, DATA
MOV DS, AX
Example Code
MOV AX, MULTIPLICAND
MUL MULTIPLIER
MOV PRODUCT, AX
MOV PRODUCT+2, DX
INT 3
CODE ENDS
END START

4. 8086 Instructions
• Data transfer
• Arithmetic
• Bit manipulation
• String
• Program execution transfer
• Processor control

5. Data Transfer Instructions
General
• MOV
• PUSH
• POP
• PUSHA
• POPA
• XCHG
• XLAT

6. MOV Destination, Source
• MOV CX, 045FH
• MOV BL, [43E4H]
• MOV AX, DX
• MOV DH, [BX]
• MOV DS, BX
• MOV RESULTS[BP], AX

7. PUSH Source
• PUSH BX
• PUSH DS
• PUSH TABLE[BX]
POP Destination
• POP BX
• POP DS
• POP TABLE[BX]

8. • PUSHA
• POPA
• XLAT / XLATB
XCHG Destination, Source
• XCHG AX, BX
• XCHG AL, CH
• XCHG AL, PRICES[BX]

9. Data Transfer Instructions
• IN
Simple IO port transfer
• OUT
• LEA
Special address transfer
• LDS
• LES
• LAHF
• SAHF Flag transfer
• PUSHF
• POPF

10. IN Accumulator, Port
• IN AL, 0C4H
• IN AX, 34H
OUT Port, Accumulator
• OUT 3BH, AL
• OUT 2CH, AX

11. LES Register, Memory addr of first word
• LES BX, [789AH]
• LES DI, [BX]
LEA Register, Source
• LEA BX, PRICES
• LEA BP, SS:STACK_TOP
• LEA CX, [BX][DI]

12. LDS Register, Memory addr of first word
• LDS BX, [789AH]
• LDS DI, [BX]

13. Flag Transfer Instructions
• LAHF [Load AH With Flags]
• SAHF [Store AH in Flags]
• PUSHF [Push flags on stack]
• POPF [Pop stack top to flags]

14. Arithmetic Instructions
• ADD • AAS
• ADC • DAS
• INC • MUL
• AAA • IMUL
• DAA • AAM
• SBB • DIV
• SUB • IDIV
• DEC • AAD
• NEG
• CBW
• CMP
• CDW

15. ADD Destination, Source
• ADD AL, 74H
• ADD CL, BL
• ADD DX, BX
• ADD DX, [SI]
ADC Destination, Source
• ADC AL, 74H
• ADC CL, BL
• ADC DX, BX
• ADC DX, [SI]

16. INC Destination
• INC BL
• INC CX
• INC VARIABLE
AAA [ASCII Adjust Accumulator After Addition]
DAA [Decimal Adjust Accumulator After Addition]

17. SUB Destination, Source
• SUB CX, BX
• SUB CH, AL
• SUB AX, 4563H
• SUB PRICES[BX], 04H
SBB Destination, Source
• SBB CX, BX
• SBB CH, AL
• SBB AX, 4563H

18. DEC Destination
• DEC AL
• DEC BP
• DEC VARIABLE
NEG Destination
• NEG AL
• NEG BX
• NEG BYTE PTR[BX]

19. CMP Destination, Source
• CMP AL, 01H
• CMP BH, CL
• CMP CX, TEMP_MIN
• CMP TEMP_MIN, CX
AAS [ASCII Adjust Accumulator For Subtraction]
DAS [Decimal Adjust Accumulator For Subtraction]

20. MUL Source
• MUL BH
• MUL CX
• MUL BYTE PTR[BX]
AAM
[BCD Adjust Accumulator After Multiply]

21. DIV Source
• DIV BH
• DIV CX
• DIV BYTE PTR[BX]
AAD
[Binary Adjust Accumulator Before Division]

22. CBW
Convert Signed Byte to Signed Word
CWD
Convert Signed Word to Signed Double Word

23. Bit Manipulation Instructions
Logical Shift Rotate
• NOT • SAL • ROL
• AND • SHL • RCL
• OR • SAR • ROR
• XOR • SHR • RCR
• TEST

24. NOT Destination
• NOT BX
• NOT BYTE PTR[BX]
AND Destination, Source
• AND BH, CL
• AND CX, [SI]
• AND BX, 00FFH
• AND DX, BX

25. OR Destination, Source
• OR BH, CL
• OR CX, [SI]
• OR BX, 00FFH
• OR DX, BX
XOR Destination, Source
• XOR BH, CL
• XOR BP, DI
• XOR DX, BX

26. TEST Destination, Source
• TEST BH, CL
• TEST CX, [SI]
• TEST BX, 00FFH
• TEST DX, BX

27. SAL / SHL Destination, Count
• SAL BX, 01
• SAL BP, CL
• MOV CL, 04H
• SAL AL, CL
C B7 B6 B5 B4 B3 B2 B1 B0
0 1 0 1 1 0 1 1 1
1 0 1 1 0 1 1 1 0

28. SHR Destination, Count
• SHR BP, 01
• SHR AL, CL
B7 B6 B5 B4 B3 B2 B1 B0 C
0 1 0 1 1 0 1 1 1 0
0 1 0 1 1 0 1 1 1

29. SAR Destination, Count
• SAR DI, 1
• SAR AL, 01
B7 B6 B5 B4 B3 B2 B1 B0 C
1 0 1 1 0 1 1 1 0
1 1 0 1 1 0 1 1 1

30. ROL Destination, Count
• ROL AX, 1
• ROL BL, CL
C B7 B6 B5 B4 B3 B2 B1 B0
0 1 0 1 1 0 1 1 1
1 0 1 1 0 1 1 1 1

31. RCL Destination, Count
• RCL AX, 1
• RCL BL, CL
C B7 B6 B5 B4 B3 B2 B1 B0
0 1 0 1 1 0 1 1 1
1 0 1 1 0 1 1 1 0

32. ROR Destination, Count
• ROR BL, 01
• ROR AL, CL
B7 B6 B5 B4 B3 B2 B1 B0 C
1 0 1 1 0 1 1 1 0
1 1 0 1 1 0 1 1 1

33. RCR Destination, Count
• RCR BL, 01
• RCR AL, CL
B7 B6 B5 B4 B3 B2 B1 B0 C
1 0 1 1 0 1 1 1 0
1 1 0 1 1 0 1 1 1

34. Program Execution Transfer
CALL name of procedure
• CALL SQRT
• CALL BX
• CALL WORD PTR(BX)
RET

35. Jump Instructions
• JMP label
Instruction Description (Jump if) Conditions
JA/JNBE Above/Below Not Equal C=0, Z=0
JAE/JNB Above or Equal/ Not Below C=0, Z=1
JB/JNAE Below/Not Above nor Equal C=1, Z=0
JBE/JNA Below or Equal/Not Above C=1, Z=1
JC Carry flag=1 C=1
JE/JZ Equal / Zero Z=1

36. Jump Instructions
Instruction Description (Jump if) Conditions
JG/JNLE Greater/Not Less Than or C=O, Z=0
Equal
JGE/JNL Greater Than or Equal/Not S=O
Less Than
JL/JNGE Less Than/Not Greater S≠O
Than or Equal
JLE/JNG Less Than or Equal/Not S=O, Z=1
Greater Than
JNC No Carry C=0
JNE/JNZ Not Equal / Not Zero Z=0

37. Jump Instructions
Instruction Description (Jump if) Conditions
JNO Not Overflow O=0
JNP/JPO Not Parity/Parity Odd P=0
JNS Not Sign S=0
JO Overflow O=1
JP/JPE Parity/Parity Even P=1
JS Sign Flag S=1
JCXZ CX is Zero CX=0

38. Iteration Control Instructions
Instruction Description Conditions
for Exit
LOOP Loop through sequence of CX=0
instructions
LOOPE/ Loop through sequence of CX=0 or
instructions ZF=0
LOOPZ
LOOPNE/ Loop through sequence of CX=0 or
instructions ZF=1
LOOPNZ

39. Processor Control Instructions
• STC
• CLC
• CMC
• STD
• CLD
• STI
• CLI

40. External Hardware Synchronization
• HLT
• WAIT
• ESC
• LOCK
• NOP

41. Interrupt Instructions
• INT
• INTO
• IRET

42. References
• “Microprocessors and Interfacing” by Douglas
Hall, Tata McGraw Hill Publishing.