Assembly program to read two decimal numbers, then add them together and finally print out the result (in decimal ) | MASM program to add two 8-bit numbers (decimal)

assume ds:data,cs:code
data segment
num1 db ?
num2 db ?
result db ?
msg1 db 10,13,"enter first number to add : $"
msg2 db 10,13,"enter second number to add : $"
msg3 db 10,13,"result of addition is : $"
data ends
code segment
start:
mov ax,data
mov ds,ax
mov dx,offset msg1
mov ah,9h
int 21h
mov ah,1
int 21h
sub al,30h
mov num1,al
mov dx,offset msg2
mov ah,9h
int 21h
mov ah,1h
int 21h
sub al,30h
mov num2,al
add al,num1
mov result,al
mov ah,0h
aaa
add ah,30h
add al,30h
mov bx,ax
mov dx,offset msg3
mov ah,9
int 21h
mov ah,2
mov dl,bh
int 21h
mov ah,2
mov dl,bl
int 21h
mov ah,4ch
int 21h
code ends
end start