simply n00b question

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gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 07 Jan 2005, 09:01

sounds may lol, but how do i move a 8 bit to a ex 16 bit register, or 8 to 32 bit??.. FX moving AL to DX...

_________________
LOOOL

07 Jan 2005, 09:01

Dryobates

Joined: 13 Jul 2003
Posts: 46
Location: Poland

Dryobates 07 Jan 2005, 10:44

Code:

movzx dx, al ; if you want extend to zero high order byte
movsx dx, al ; if you want preserve sign

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There's one more bug... Smile

07 Jan 2005, 10:44

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 07 Jan 2005, 12:42

Thanks, just donno if it works, i trying to make one there writes back what you write, but i got a problem too again
when i do this(becuase its need a $ for end the write)
mov [dx+1],'$'
its says error with that... any other ways i can do it on and not to be greedy Rolling Eyes

how do i mov db(defined byte) to 8 bit register fx al?

07 Jan 2005, 12:42

bubach

Joined: 17 Sep 2004
Posts: 341
Location: Trollhättan, Sweden

bubach 07 Jan 2005, 13:48

La viro parolas Esperanton... Smile

07 Jan 2005, 13:48

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 07 Jan 2005, 17:03

WHAT?

07 Jan 2005, 17:03

beppe85

Joined: 23 Oct 2004
Posts: 181

beppe85 07 Jan 2005, 17:44

If you are programming in 16 bits, you do not use dx as a base register, but bx(usually) instead. On 32 bits, you must use 32 bits registers:

[codeedx+1], byte '$'[/code]

Note that I specified the size, byte.

07 Jan 2005, 17:44

bubach

Joined: 17 Sep 2004
Posts: 341
Location: Trollhättan, Sweden

bubach 07 Jan 2005, 18:08

It's a phrase in (the language) Esperanto.

Last edited by bubach on 13 Feb 2012, 15:25; edited 1 time in total

07 Jan 2005, 18:08

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 07 Jan 2005, 18:59

how do i change that? or what you saying? ps bubach, i don't understand a shit of what you saying... Razz

07 Jan 2005, 18:59

iklin

Joined: 20 Mar 2004
Posts: 120
Location: Russia, Siberia

iklin 07 Jan 2005, 20:53

bubach wrote:

La viro parolas Esperanton...

Something like "Men speak in Esperanto"?

07 Jan 2005, 20:53

Madis731

Joined: 25 Sep 2003
Posts: 2139
Location: Estonia

Madis731 07 Jan 2005, 21:26

OK, the poster have not exactly understood, where you're getting at:
I think I know what you need:

Code:

Sample db "onvrwovjw"
mov dx,Sample
mov byte[dx+10],'$' ;You don't need BYTE if you have defined "db"

;-OR-
mov edx,Sample
mov byte[edx+10],'$' ;Assembler understands that (e)dx is a byte variable(I think)

;You should use byte, word, dword for code readability or when you really would like to split DWORD into BYTEs or vice versa...

07 Jan 2005, 21:26

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 08 Jan 2005, 10:07

its becuase, with one low bit( Cool

i will may converter it to a 32 register, and also a 32 bit register i will conveter to 8 bit register... I got also another problem - its that i wanna make my program in full interrups, and found a few guides there show FindFirst & FindNextFile. And such things, but donno how to write to regedit... so my question is, how to set a reg_sz string to ms windows registry database...

08 Jan 2005, 10:07

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 08 Jan 2005, 17:45

anybody?

08 Jan 2005, 17:45

iklin

Joined: 20 Mar 2004
Posts: 120
Location: Russia, Siberia

iklin 08 Jan 2005, 18:23

RegSetValue, RegSetValueEx and other Reg....... functions from advapi32.dll

Code:

LONG RegSetValue(
    HKEY hKey,   // handle of key to set value for 
    LPCTSTR lpSubKey,     // address of subkey name 
    DWORD dwType, // type of value 
    LPCTSTR lpData,        // address of value data 
    DWORD cbData   // size of value data 
);

It's from Win32 SDK Reference help aka win32.hlp which I'm using hardly every day Smile

08 Jan 2005, 18:23

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 08 Jan 2005, 18:45

... i know the api, but it is possible to do it with interrups...?

08 Jan 2005, 18:45

f0dder

Joined: 19 Feb 2004
Posts: 3175
Location: Denmark

f0dder 08 Jan 2005, 19:18

Quote:

... i know the api, but it is possible to do it with interrups...?

What's the point? The API will work on all win32 versions, using interrupts will lock you to NT (I believe 9x uses a funky r3->r0 method involving ARPL?)

08 Jan 2005, 19:18

vid
Verbosity in development

Joined: 05 Sep 2003
Posts: 7105
Location: Slovakia

vid 08 Jan 2005, 19:22

not in windoze, you don't use interrupt there anymore (well, only in some device drivers or so).

08 Jan 2005, 19:22

f0dder

Joined: 19 Feb 2004
Posts: 3175
Location: Denmark

f0dder 08 Jan 2005, 20:01

Well, on NT you can access the native API through interrupts... but the question is why you'd want to do it (at least for regular programs).

08 Jan 2005, 20:01

iklin

Joined: 20 Mar 2004
Posts: 120
Location: Russia, Siberia

iklin 08 Jan 2005, 20:14

Are you wanted something like this? Accesing to registry without APIs?
Maybe author of this tool can help you...

Description:	RegView (for DOS, without APIs)	Download
Filename:	regv.rar
Filesize:	21.7 KB
Downloaded:	448 Time(s)

08 Jan 2005, 20:14

gumletis

Joined: 18 Dec 2004
Posts: 128

gumletis 09 Jan 2005, 15:48

there is no source in it...

09 Jan 2005, 15:48

iklin

Joined: 20 Mar 2004
Posts: 120
Location: Russia, Siberia

iklin 09 Jan 2005, 20:59

Yes! And what? You can simply email the author or you can re-engeneering this file and try to understand the algorithms and concepts. Asm-coding is teaching us to dive deeper, imho.
Look at Privalov or JonhFound! They are incredible men! And I'm just an amateur next to them.
Well... If registry contains any kind of information it must have the format. And somethere in the world there is description of this format. And if you couldn't get it you can try to understand it by yourself.
But don't forget that registry format had changed from version to version. And this is may cause a problem...
Good luck! Smile

09 Jan 2005, 20:59

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