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;converting a value to it's ascii representation of binary

.486

.model flat,stdcall

option casemap:none



include \masm32\include\windows.inc

include \masm32\include\masm32.inc

include \masm32\include\gdi32.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc





includelib \masm32\lib\masm32.lib

includelib \masm32\lib\gdi32.lib

includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib





.data

;myarray db '0123456789ABCDEF',0

buff    db 8 dup(?)

titlestring db "ascii2binary",0

szformat db "%u",0



.data?



.code

start:

    xor     eax,eax

    xor     ecx,ecx

    ;mov     ecx,8

    mov     eax,42 ;hex value for ascii character A

do_again:

    shr     eax,1

    

    jne      once_more

    mov     [buff+ecx],'0'

    inc     ecx

    cmp     ecx,8

    jc     done

    jmp     do_again

    

once_more:

    mov     [buff+ecx],'1'

    inc     ecx

    

    ;jnc   done

    jmp     do_again

done:  

    invoke wsprintf,ADDR buff,ADDR szformat,eax

    invoke MessageBox,0,ADDR buff,ADDR titlestring,MB_OK

    invoke ExitProcess,0

end start

it gives me only decimal numbers why is that?

Only other way, with more data :D (dunno if is correct ...)

ascii0 db '0000',0

ascii1 db '0001',0

..

asciiF '1111',0



arrayOfAddr dd ascii0, ascii1,..., asciiF



xor eax, eax

mov al, value

mov ecx, eax

shr ecx, 4

mov eax, [arrayOfAddr+eax*4]

invk strcpy, buffer, eax

lea eax, [bufferOfAddr+4]

mov ecx, [array+ecx*4]

invk strcpy, eax, ecx

???


Have a nice day or night.

Here's how I did figure it out after playing with it last night

;converting a value to it's ascii representation of binary



.486

.model flat,stdcall

option casemap:none



include \masm32\include\windows.inc

include \masm32\include\masm32.inc

include \masm32\include\gdi32.inc

include \masm32\include\user32.inc

include \masm32\include\kernel32.inc





includelib \masm32\lib\masm32.lib

includelib \masm32\lib\gdi32.lib

includelib \masm32\lib\user32.lib

includelib \masm32\lib\kernel32.lib





.data

hex_chars db '0123456789ABCDEF',0

buff    db 8 dup(?)

titlestring db "ascii2binary",0

szformat db "%u",0



.data?



.code

start:

    xor     eax,eax

    xor     ecx,ecx

    xor     ebx,ebx

    lea     esi,hex_chars

    lea     edi,buff



    mov     eax,42 ;value 

    push    eax ;save this value

    and     al,0F0h ;isolate upper nibble

    shr     eax,4    ;adjust the upper nibble so it is in bits 0-3

    mov     dl,[esi+eax]

    mov     [edi],dl

    inc     edi

    pop     eax

    and     al, 0Fh ;isolate lower nibble

    ;shr     eax,4

    mov     dl,[esi+eax]

    mov     [edi],dl

    inc     edi

    mov     byte ptr [edi],0

 

    ;invoke wsprintf,ADDR buff,ADDR szformat,edi

    invoke MessageBox,0,ADDR buff,ADDR titlestring,MB_OK

    invoke ExitProcess,0

end start

thanxs for your replies

Blah, why did you write binary then? Lol.

If you want to convert to hex, then you might as well do it this way:

.486

.model flat

.includelib \masm32\lib\user32.lib

.includelib \masm32\lib\kernel32.lib

.code

titlestring "ascii2binary",0

start:

mov edi,addr buff

push 0

push addr titlestring

push edi

mov al,42

bswap eax

push 2

pop ecx

@@:

rol eax,4

and al,15

daa

cmp al,16

sbb al,207

stosb

loop @B

mov [edi],cl

push ecx

call [__imp__MessageBox@16]

push 0

call [__imp__ExitProcess@4]

end start

No, you understood me right that was my
intentions. But later out of frusation I wrote it that way. Forgive me so bascially I could shift the bits off to get it's binary value huh?:confused:

How can I make this a function, instead of a macro the programmer's ref for MASM
did not talk about writing procs

The one that you put is not exaclty a macro, is more a function because it have a entry point and exit point(some functions have more that one exit point) and a portion of code (or data that will be readed as code ) that will be executed, sure that the function dont have a name, the start is only marked with start:


A function is that, make operations and return some, stricly a function is diferent from a procedure but normally I dont diferentiate them (in programming because I see that a procedure is at the end like a hided function... I am navigating you with my opinions no??), ok.


A function is basically a block of code for do some, like donkey say, between assemblers is not so widely used only one way for mark a block of code that mean a function.



When a function is writed, you only need to aproach the function objetive, you dont care exactly on how the arguments are passed to the function but more how they are manipulated inside and what they are or mean.

Because a function is a block of code with specific meaning (or objetive), you need mark this block in some way and give this block a name inside your code (and in that way, you can call it with that name). Maybe there are two way in general for mark the block.


functionNAME markOfStartFunction
BLOCK
markOfEndFunction

markOfStartFunction functionNAME
BLOCK
markOfEndFunction


Also you will only mark blocks of code, and normally not data ;), because data mean for you some, but if the computer try execute it, maybe it will cause some errors, and yes code is also data only when is executed (marked with eip) have meaning of code, see that this diference is only at level of computer, because for us data is data, and code is code :D.


Have a nice day or night.