Random number in TASM

[Revos]

Hi..

I checked out the forum for any random number code in asm and the only thing I found was too complicate plus it was in MASM.

My question is, is there any way I can generate a random number in the range of 1 - 100 or something like that?

Thanks for reading ^ ^

[DrPepUr]

I dunno about Tasm but in Masm u can use masm.lib

Invoke nrandom,100

[Ufo-Pu55y]

Like MOID recently mentioned.. check out advapi's crypt functions.

I also switched from masm32's random function to advapi:

	include				advapi32.inc
	includelib			advapi32.lib.const
	PROV_RSA_FULL		equ	1
	CRYPT_VERIFYCONTEXT	equ	0F0000000h.data?
	hProv				dd	?
	ddRandom			dd	?.code
	invoke CryptAcquireContext,addr hProv,NULL,NULL,PROV_RSA_FULL,CRYPT_VERIFYCONTEXT
	invoke CryptGenRandom,hProv,sizeof DWORD,addr ddRandom
	invoke CryptReleaseContext,hProv,NULL

I never used tasm, but that should be doable :?

In case you need random bytes in a defined range, I wrote and used following function:

GetRandomByte proc prov:DWORD,min:BYTE,max:BYTE
	LOCAL output:BYTE	.repeat
		invoke CryptGenRandom,prov,1,addr output
		mov al,output
	.until al >= min && al <= max	ret
GetRandomByte endp

.. so you could use it like:

invoke CryptAcquireContext,addr hProv,NULL,NULL,PROV_RSA_FULL,CRYPT_VERIFYCONTEXT
invoke GetRandomByte,hProv,'A','Z'
; al = random byte 'A'...'Z'
invoke CryptReleaseContext,hProv,NULL

[Revos]

The only reason I am using tasm is because we are using it in school and that what we are being taught..

Thanks for the fast replies but is there any way to generate a random number without any includes?

If not..is there any way to make something like a loop from 1 to 100 and make the computer choose when to stop the loop? I mean is there and range of numbers that I can get in ASM and it is not static range?

[HVC]

Hi Revos,

Here's the source to a PRNG in ASM. It should, with none or minor modifications, be usable in TASM.

Sorry, don't have TASM to help you, but try it, and post here if you don't succeed.

Someone will help you...

http://www.tuts4you.com/download.php?view.501

Edited May 27, 2008 by HVC

[Revos]

Well..checked it, again in tasm there isn't something like GetTickCount..so thats a problem =\

I thought its too difficult to make a random number with tasm so I got an idea..tell me if it is possible.

I will write to the user "Computer is choosing number, press any key to stop" and meanwhile I will make a loop from 1 to 100 that goes on and on again and again until any key is pressed..

something like this:

while (not any key pressed)

{

if (a==100)

a=1;

a++;

}

I am going to try it..if I success I will post it

Thanks for helping ^ ^

Edited May 27, 2008 by Revos

[HVC]

Hmm

Unless you have to do your project in 16-bit, ofcourse you can use GetTickCount.

Else, take a look at this source here...

http://www.programmersheaven.com/download/1372/download.aspx

or this:

http://www.programmersheaven.com/download/1372/download.aspx

Edited May 27, 2008 by HVC

[Revos]

I have to do it in 16 bit..

I looked at your links and those source codes and I have to say..I didn't understand anything from it.

Thats why I am trying to do what I said but the problem is..how can I wait for any key to be pressed and run a loop..I know how to do each of them alone, but together? this is what I did so far..

				getchar:
						mov ah, 01h
						int 21h
						ret	RandomNum:
			mov al, 1
			again:
		cmp al, 100
		je put_1_in_al
		inc al
		jmp again
			put_1_in_al:
				mov al, 1
				jmp again
			 ret

I have no clue how to mix them..anyone help?

[enhzflep]

Hi, I have some old code that may be of use to you Revos.

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

seedrand

push di

les di, [timer]

mov eax, [es:di] ; get timer tick count

mov [seed], eax ; and use to seed our random gen

push cs

pop es

pop di

ret

;

PART.ZIP

Edited May 27, 2008 by enhzflep