Write an assembly program that:
- Multiply the content of AL by 5. Use a loop to implement the multiplication (Do not use MUL or IMUL).
- The result will be shown in port 0 in the trainer kit.
Assuming that the trainer kit's port 0 is the output port, here is an example program in x86 assembly language that multiplies the content of the AL register by 5 using a loop:
; Set up the data segment and variables
segment data
multiplier db 5 ; constant multiplier for the loop
result db 0 ; initialize the result variable to 0
endseg
segment code
assume cs:code, ds:data
start:
; Load the value to be multiplied into AL
mov al, 7
; Multiply AL by 5 using a loop
mov cl, multiplier ; load the multiplier into CL
mov bl, al ; move the value of AL into BL for intermediate calculations
multloop:
add al, bl ; add the value of BL to AL, effectively multiplying it by 2 in each iteration
dec cl ; decrement the loop counter
jnz multloop ; jump back to the loop if the counter is not zero
; Store the final result in the result variable
mov result, al
; Output the result to port 0 in the trainer kit
out 0, al
; Halt the program
hlt
end start
Here is an example of an assembly program that multiplies the content of AL by 5 and displays the result in port 0:
```
org 100h ; Set the origin address
section .data
result db 0 ; Define a variable to store the result
count dw 5 ; Define a counter variable
section .text
global _start
_start:
mov al, 5 ; Move the value 5 into AL register
mov cx, count ; Move the count value into CX register
multiplication_loop:
add result, al ; Add the value of AL to the result variable
loop multiplication_loop
mov dx, result ; Move the result value into DX register
mov ah, 02h ; Set the print function code
mov al, dl ; Move the lower 8 bits of DX into AL
int 21h ; Display the result in the trainer kit's port 0
mov ah, 4Ch ; Set the exit function code
int 21h ; Exit the program
```
This program uses a loop to implement the multiplication by 5 by repeatedly adding the value of AL to the result variable. The loop runs for a specified number of times (5 in this case) using the `loop` instruction.
After the multiplication, the result is stored in the `result` variable and then displayed in port 0 using the appropriate interrupt call (`int 21h` with function code 2).
Finally, the program exits using the `int 21h` interrupt call with function code 4Ch.