> .model large
> .stack 64
> .data 
>   num1 db 6 dup(' ')
>   num2 db 6 dup(' ')
>   num3 db 6 dup(' '),"$"
>   num dw 0
>   dolar db "$"
>   msg1 db 13,10,"num1 : $",13,10
>   msg2 db 13,10,"num1 : $",13,10
>   msg3 db 13,10,"res : $",13,10
> .code
> main proc far
> mov ax,@data
> mov ds,ax
> 
> call cls
> 
> mov ah,9
> lea dx,msg1
> int 21h
> 
> lea dx,num1
> call get_num
> mov bx,num
> 
> 
> mov ah,9
> lea dx,msg2
> int 21h
> 
> lea dx,num2
> call get_num
> 
> add bx,num
> mov dx,0
> mov cx,10
> div cx
> add dl,30h
> 
> mov ah,9
> lea dx,msg3
> int 21h
> 
> mov num3,dl
> 
> mov ah,9
> lea dx,num3
> int 21h
> 
> mov ax,4c00h
> int 21h
> main endp
> 
> cls   proc       far
>          push      ax
>          push      bx
>          push      dx
>          pushf   
>          mov      ah, 6h   ;clear screen
>          mov      al, 25   ;number of rows
>          mov      ch, 0
>          mov      cl, 0
>          mov      dh, 24   ;row
>          mov      dl, 79   ;column
>          mov      bh, 7    ;attribute
>          int      10h
>          popf
>          pop      dx
>          pop      bx
>          pop      ax
>          
>          retf
> 
> cls   endp
> get_num       proc       far       
>             push    bp 
>             mov     bp, sp
>             push      si 
>             push      bx
>             push      cx
>             push      dx
> 
>             
>             mov     ah, 3fh
>             mov     dx, [bp+06] 
>             mov     bx, 0000h
>             mov     cx,8
>             int     21h
> 
>               
>               mov      si, dx 
> while_blank:  cmp      byte ptr [bx], ' '        ; skip leading blank
>               jne      end_while_blank   ; exit while
>               inc      bx
>               jmp      while_blank
> end_while_blank:
>               mov      bl, 1               ;default sign multiplier
>               cmp      byte ptr [si], '+'  ;leadin + ?
>               je       skip_sign           ;if so skip over
>               cmp      byte ptr [si], '-'  ;leading - ?
>               jne      save_sign           ;if not save default +
>               mov      bl, -1              ;-1 for minus sign
> skip_sign:    inc      si                  ;past sign
> 
> save_sign:    mov      ax, 0               ;number being accumulated
>               mov      bh, 0               ;count of digits so far
> while_digit:  cmp      byte ptr [si], '0'  ;compare next car to '0'
>               jl       end_while_digit     ;if not a digit exit
>               cmp      byte ptr [si], '9'  ;compare to '9'
>               jg       end_while_digit     ;not a digit if bigger than '9'
>               mov      cx, 10              ;multiplier
>               mul      cx                  ;multiply old number by 10
>               mov      cl, [si]            ;mov ascii char to bl
>               and      cx, 000fh           ;convert to single digit integer
>               add      ax, cx              ;add to sum
>               inc      bh               ;increment digit count
>               inc      si                  ;increment character pointer
>               jmp      while_digit         ;go next char
> end_while_digit:
>               ; imul      bl
>                cmp        bl, 1
>                je         exit1
>                neg        ax
>             exit1:
>                mov       num, ax
>               
>               pop      dx
>               pop      bx
>               pop      cx
>               pop      si 
>               pop       bp
> 
>                retf 2
> get_num        endp
> 
> 
> convert_num_string   proc      far
> 
>               push      bp
>               mov       bp, sp
>               push      si 
>               push      ax
>               push      bx
>               push      cx
>               push      dx
>               mov      ax, word ptr[bp+08]
>               mov      si, word ptr[bp+06]
> 
>               add      si, 5
>               mov      bh, ' '
>               cmp      ax, 0
>               jge      setup         ; skip if not negative
>               mov      bh, '-'
>               neg      ax            ; now ax > 0
> 
> setup:        mov      cx, 10        ; divisor
> divloop:      mov      dx, 0         ; extend number to double word
>               div      cx            ; divide by 10
>               add      dl, 30h       ; convert
>               mov      [si], dl
>               dec      si
>               cmp      ax, 0
>               jne      divloop
>               mov      cl, bh       ; insert sign to string
>               mov      [si], cl
>               
>               pop      dx
>               pop      bx
>               pop      cx
>               pop      ax
>               pop      si
>               pop       bp
>               
>               retf     4
> 
> convert_num_string   endp
> end main