Please help and teach me :)

Index > Main > Please help and teach me :)

Author

Thread

mastek

Joined: 29 Jun 2006
Posts: 17

mastek 08 Apr 2015, 09:06

Hello. I am new and beginner about assembler. I choose fasm because it is updating always.

I have C code simple program (source below). But I could not convert fasm code. Can you help me ?

I want to convert fasm 32 bit dos (I love DOS Smile

and Win 32 Window application

Would you tech me ?

best regards

C code :

#include <stdio.h>

int main

{
printf(" Hello World 1 \n");
printf(" Hello World 2 \n");
printf(" Hello World 3 \n");

return 0;
}

08 Apr 2015, 09:06

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20518
Location: In your JS exploiting you and your system

revolution 08 Apr 2015, 09:08

The "hello World" source codes for various systems are already included in the fasm download. See the folder named "examples".

08 Apr 2015, 09:08

CandyMan

Joined: 04 Sep 2009
Posts: 414
Location: film "CandyMan" directed through Bernard Rose OR Candy Shop

CandyMan 08 Apr 2015, 15:16

the simplest examples

Code:

        org     100h

        mov     bx,Hello
        call    PrintStr
        mov     byte [bx+12],'2'
        call    PrintStr
        mov     byte [bx+12],'3'
PrintStr:
        mov     ah,9
        mov     dx,bx
        int     21h
        ret

Hello   db      'Hello World 1',13,10,36

Code:

        org     100h

        call    PrintStr
        call    PrintInc
PrintInc:
        inc     byte [Hello+12]
PrintStr:
        mov     ah,9
        mov     dx,Hello
        int     21h
        ret

Hello   db      'Hello World 1',13,10,36

Code:

        org     100h

        mov     cx,3
      @@:
        mov     ah,9
        mov     dx,Hello
        int     21h
        inc     [Hello+12]
        loop    @B
        ret

Hello   db      'Hello World 1',13,10,36

_________________
smaller is better

08 Apr 2015, 15:16

mastek

Joined: 29 Jun 2006
Posts: 17

mastek 08 Apr 2015, 20:17

CandyMan wrote:

the simplest examples

Code:

        org     100h

        mov     bx,Hello
        call    PrintStr
        mov     byte [bx+12],'2'
        call    PrintStr
        mov     byte [bx+12],'3'
PrintStr:
        mov     ah,9
        mov     dx,bx
        int     21h
        ret

Hello   db      'Hello World 1',13,10,36

Code:

        org     100h

        call    PrintStr
        call    PrintInc
PrintInc:
        inc     byte [Hello+12]
PrintStr:
        mov     ah,9
        mov     dx,Hello
        int     21h
        ret

Hello   db      'Hello World 1',13,10,36

Code:

        org     100h

        mov     cx,3
      @@:
        mov     ah,9
        mov     dx,Hello
        int     21h
        inc     [Hello+12]
        loop    @B
        ret

Hello   db      'Hello World 1',13,10,36

@CandyMan

thank you soo much. Can you show me 32 bit unreal mode and win32 window versions?

08 Apr 2015, 20:17

CandyMan

Joined: 04 Sep 2009
Posts: 414
Location: film "CandyMan" directed through Bernard Rose OR Candy Shop

CandyMan 09 Apr 2015, 12:53

in 32-bit unreal mode sample is the same as real mode
see also:
http://board.flatassembler.net/topic.php?p=134745#134745
http://board.flatassembler.net/topic.php?p=145936#145936
http://board.flatassembler.net/topic.php?p=104631#104631

_________________
smaller is better

Last edited by CandyMan on 14 Apr 2015, 17:48; edited 1 time in total

09 Apr 2015, 12:53

mastek

Joined: 29 Jun 2006
Posts: 17

mastek 10 Apr 2015, 12:50

CandyMan wrote:

in 32-bit unreal mode sample is the same as real mode
see also:
http://board.flatassembler.net/topic.php?p=134745#134745
http://board.flatassembler.net/topic.php?p=145936#145936
http://board.flatassembler.net/topic.php?p=104631#104631

Thank you candyman.

Time to work for me Smile

10 Apr 2015, 12:50

El Tangas

Joined: 11 Oct 2003
Posts: 120
Location: Sunset Empire

El Tangas 24 May 2015, 23:05

Here is an example for windows command line:

Code:

format PE console  ;this is a command line program

include 'win32ax.inc'  ;load standard fasm macros for windows


define  \n 13,10  ;define newline as convenience for C programmers 

.code
start:
        invoke  GetStdHandle,STD_OUTPUT_HANDLE    ;windows funtion that returns handle to STDOUT
        mov     [handle],eax                      ;save handle
        invoke  WriteFile,[handle],string1,str_len1,n_written,0   ;this windows functtion is similar to C "fwrite"
        invoke  WriteFile,[handle],string2,str_len2,n_written,0   ;since we are not using printf formating anyway
        invoke  WriteFile,[handle],string3,str_len3,n_written,0   ;there is a wsprintf function in windows if you really need it

        mov     eax,0   ;these 2 lines are C "return 0;"
        ret

.data

string1 db "Hello, World!!! 1",\n
str_len1 = $-string1   ;to calculate the lenght of the string

string2 db "Hello, World!!! 2",\n
str_len2 = $-string2

string3 db "Hello, World!!! 3",\n
str_len3 = $-string3

n_written dd 0   ;we don't use this variable, but WriteFile requires it...
handle dd 0

.end start      ;.end is a very convenient standard fasm macro

To get details on windows functions, you can check msdn. I used 3 strings instead of a dynamically modifying string like CandyMan did, for clearness. So, you can try to write the windows version of the modifying code as exercise Smile

BTW, I notice you registered here in 2006 Shocked

lol, you post even less than me Laughing

24 May 2015, 23:05

< Last Thread | Next Thread >

Forum Rules:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum