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Random number generator in 16-bit DOS assembly

Most code for randomizing is not as short as this one. Try to incorporate this procedure in your code and see how it works!



randomize:
        in al, 40h	; read micro-clock for initial seed
        mov ah, al
        in al, 40h
        xchg al, ah
        or ax, 1
        mov rnum, ax
ret

Random number will be stored in rnum. Fairly straightforward isn’t it?


[Edit]


Here’s another solution by sir Eugene Kanindot. This is a 3-digit random number generator.



jmp start
	
xxx:
mov ah, 02ch
int 21h
and dl, 0fh
cmp dl, 9
ja xxx
add dl, 30h
mov [di], dl
ret
	
delay:
mov cx, 0
	
yyy:
mov dx, 0a00h
	
zzz:
xor ax, ax
dec dx
cmp dx, 0
jne zzz
	
loop yyy
ret
	
start:
lea di, numb
call xxx
inc di
call delay
call xxx
inc di
call delay
call xxx
mov ah, 09h
lea dx, numb
int 21h
int 20h
	
numb db 4 dup('$')
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