How to add two numbers in 8086 Assembly language

 

Use of AAA instruction

The AAA instruction is only useful when it follows an ADD instruction that adds (binary addition) two unpacked BCD values and stores a byte result in the AL register. The AAA instruction then adjusts the contents of the AL register to contain the correct 1-digit unpacked BCD result.

Sample program 

.model small

.stack 100h

.data

msg1 db "Enter first number:$"

msg2 db 10d,"Enter second number:$"

msg3 db 10d,"Addition is:$"

.code

mov ax,@data

mov ds,ax

mov ah,09h

mov dx,offset msg1

int 21h

mov ah,01h

int 21h

mov cl,al

mov ah,09h

mov dx,offset msg2

int 21h

mov ah,01h

int 21h

mov ch,al

add ch,cl

mov al,ch

mov ah,00h

AAA

mov ch,ah

mov cl,al

mov ah,09h

mov dx,offset msg3

int 21h

mov dl,ch

add dl,30h

mov ah,2

int 21h

mov dl,cl

add dl,30h

mov ah,2

int 21h

mov ah,4ch

int 21h

end

Output

Download Tasm or Turbo Assembler here