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.model small
.stack 64
.DATA
number1 db 20 dup(55h)
number2 db 20 dup (55h)
result_with_mul db 20 dup (55h)
result_without_mul db 20 dup (55h)
msg1 db 'pls enter the first number with 2 digits: $ ',0ah,0dh
msg2 db 0ah,0dh,'pls enter the second number with 2 digits: $ ',0ah,0dh
msg3 db 'conclusion: results with and without mul are equal $'
msg4 db ' conclusion: results with and without mul are not equal $'
;msg5 db 'error you have enter not what u need to pls try again $'
.CODE
begin proc far
mov ax,@data
mov ds,ax
mov es,ax
lea di,number1
push di
lea di,number2
lea dx,msg1
push dx
call disp_msg
call get_2_digits
lea dx,msg2
push dx
call disp_msg
call get_2_digits
call with_mul
call without_mul
cmp al,dl
je msg_equal
jne msg_not_equal
msg_equal: lea cx,msg3
push cx
&nbs p;
&n bsp;
call disp_msg
msg_not_equal: lea cx,msg4
push cx
call disp_msg
mov ax,4c00h
int 21h
begin endp
;-------------------------------------
disp_msg proc
push bp
mov bp,sp
push dx
mov dx,[bp+4]
call print
pop dx
pop bp
ret 2
disp_msg endp
;------------------------------------------
print proc
mov ah,09h
int 21h
ret
print endp
;--------------------------------------------
get_1_digit proc near
again: call get_char
cmp al,'0' ; check if digit
jl again
cmp al,'9' ;filter 4 digits
jg again
sub al,30h ;de-ascii
ret
get_1_digit endp
;---------------------------------------------
get_2_digits proc near
;convert 2 ascii digits into number -->bl
push ax
call get_1_digit
shl al,1 ;*2
mov bl,al ;save
shl al,1 ;*4
shl al,1 ;*8
add bl,al ;10
call get_1_digit
add bl,al
pop ax
ret
get_2_digits endp
;------------------------
get_char proc
;
mov ah,1
int 21h
ret
get_char endp
;------------------------
;_____________________________
with_mul proc
push bp
mov & nbsp; bp, sp
&n bsp;
;Another stack pointer besides sp
push dx ;Saving the current values
of the registers
push si
xor & nbsp; bx,
bx ;Prepering place for the result
mov & nbsp; si,
[bp+4] ;Reading data from the stack
mov & nbsp; al,
[si] ;The value of the multiplicant
inc si
mov & nbsp; dh,
al ;Copy of the multiplicant
mov & nbsp; ah,
[si] ;The value of the multiplier
mov & nbsp; dl,
-1 ;In dl the place of each bit is been saved
mov & nbsp; cx,
8 ;The length of one byte
next_bit:
shr & nbsp;
al, &n bsp; 1 ;Saving the
place of each bit in order to know the "weight" of it
inc & nbsp;
dl ;Pl ace 0 = weight 1, place 1 = weight 2,
place 2 = weight 4 etc
jc &n bsp; &nbs p;
multi ;If the carry fleg is '1' binary we have to add the
bit's weight to the result
loop next_bit
jmp & nbsp; skip ;Reaching to this
line only when the loop ends
multi: ;Result=(weight*multiplier)+re sult
push ax; Saving the current
value of ax
mov & nbsp; al,
ah ;Duplicate of the multiplier
xor ah, ah
push cx ;Saving the counter of
the external loop
mov cl, dl
shl & nbsp;
ax, &n bsp; cl ;Temporary result
=(weight*multiplier)!!!
add & nbsp; bx, ax
;In the end of the loop the result will be saved in bx
pop cx
pop ax
loop next_bit
skip: ;This part calculate the result by using the mul function
mov & nbsp; al,
dh ;dh=the value of the multiplier
mul & nbsp; ah ;The multiplier
is already exist at al (result=al*ah=ax)!!!
pop si
pop & nbsp;
dx ;Cl eaning the stack
pop bp
ret
with_mul endp
;----------------------------------
without_mul proc ;Building the tens digit by multiplying – (origin digit)*10
mov & nbsp; bl,
al ;duplicating the origin digit
shl & nbsp;
bl, &n bsp; 1 ;(The origin digit)*2
push cx ;saving the current value of
the external loop
mov cl, 3
shl al, cl ;(The origin digit)*8
add & nbsp; bl,
al ;The result saved in bl
pop cx
ret
without_mul endp
;-----------------------------------
end
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