8086 program To multiply two 8 bit numbers
02:59
ØØ Explanation :
· Consider that a byte of data is present in the AL register and second byte of data is present in the BL register.
· We have to multiply the byte in AL with the byte in BL.
· The multiplication of two 8 bit numbers may result into a 16 bit number. So result is stored in AX register.
· The MSB is stored in AH and LSB in AL.
For example :
|
AL = 09 H
|
09 H
| |
BL = 02 H
|
´
|
02 H
| |
0012 H
|
ØØ Algorithm :
Step I : Initialise the data segment.
Step II : Get the first number in AL register.
Step III : Get the second number in BL register. Corel - 3
Step IV : Multiply the two numbers.
Step V : Display the result.
Step VI : Stop
ØØ Flowchart : Refer flowchart 10.
ØØ Program :
.model small
.data
a db 09H
b db 02H
.code
mov ax, @data ; Initialize data section
mov ds, ax
mov ah, 0
mov al, a ; Load number1 in al
mov bl, b ; Load number2 in bl
mul bl ; multiply numbers and result in ax
mov ch, 04h ; Count of digits to be displayed
mov cl, 04h ; Count to roll by 4 bits
mov bx, ax ; Result in reg bx
l2: rol bx, cl ; roll bl so that msb comes to lsb
mov dl, bl ; load dl with data to be displayed
and dl, 0fH ; get only lsb
cmp dl, 09 ; check if digit is 0-9 or letter A-F
jbe l4
add dl, 07 ; if letter add 37H else only add 30H
l4: add dl, 30H
mov ah, 02 ; Function 2 under INT 21H (Display character)
int 21H
dec ch ; Decrement Count
jnz l2
mov ah, 4cH ; Terminate Program
int 21H
end
ØØ Result :
C:\>tasm 8bit-mul.asm
Turbo Assembler Version 3.0 Copyright (c) 1988, 1991 Borland International
Assembling file: 8bit-mul.asm
Error messages: None
Warning messages: None
Passes: 1
Remaining memory: 438k
C:\>tlink 8bit-mul.obj
Turbo Link Version 3.0 Copyright (c) 1987, 1990 Borland International
Warning: No stack
C:\>8bit-mul
0012
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