8086 Programs: Basic operations on two BCD Numbers

Basic operations such as addition and subtraction will be performed on two BCD numbers using Assembly programming.

Addition of two BCD Numbers

Aim:

To perform the addition of two BCD numbers using Assembly language for 8086 microprocessor.

Software Used:

MASM

Program Code:

CODE SEGMENT
        ASSUME CS:CODE
        ORG 1000H
        MOV SI,1100H
        MOV CL,00H
        MOV AX,[SI]
        MOV BX,[SI]+2
        ADD AL,BL
        DAA
        MOV DL,AL
        MOV AL,AH
        ADC AL,BH
        DAA
        MOV DH,AL
        JNC SKIP
        INC CL
SKIP: MOV [SI+4],DX
        MOV [SI+6],CL
        HLT
CODE ENDS
        END

Sample Input and Output:

Operand 1: 3378h
Operand 2: 8698h

Input		Output
Address	Data	Address	Data
3000	78	3004	76
3001	33	3005	20
3002	98	3006	01
3003	86

Result: 

Sum = 2076h, Carry = 01h

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Subtraction of two BCD Numbers

Aim:
To perform the subtraction of two BCD numbers using Assembly language for 8086 microprocessor. 

Software Used:
MASM

Program Code:
CODE SEGMENT
        ASSUME CS:CODE
        ORG 1000H
        MOV SI,1100H
        MOV CL,00H
        MOV AX,[SI]
        MOV BX,[SI+2]
        SUB AL,BL
        DAS
        MOV DL,AL
        MOV AL,AH
        SBB AL,BH
        DAS
        MOV DH,AL
        JNC SKIP
        INC CL
SKIP: MOV [SI+4],DX
        MOV [SI+6],CL
        HLT
CODE ENDS
        END

Sample Input and Output:

Operand 1: 9572h
Operand 2: 4793h

Input		Output
Address	Data	Address	Data
3000	72	3004	79
3001	95	3005	47
3002	93	3006	00
3003	47

Result: 

Difference = 4779h, Borrow = 00h