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From: "Develop.ReactOS" <develop.reactos@gmail.com>
To: "gdb" <gdb@sourceware.org>
Subject: Need help debuging i386 in real mode.
Date: Sun, 25 Mar 2007 06:35:00 -0000	[thread overview]
Message-ID: <200703251435091123125@gmail.com> (raw)

Hello:
    I am trying to debug i386 in real mode. How to disassemble 16-bit code?
    gdb appears to always assume a 32-bit segment.Is there a way to coerce gdb into 16-bit disassembly mode?  Is there some other tool or cmd I could use?  

I need 16-bit disassembly instruction,but gdb's output is wrong:
(gdb) x /10i $eip+$cs*16
0xffff0:        ljmp   0x3131,0xf000e05b
0xffff7:        das
0xffff8:        xor    BYTE PTR [ecx],dh
0xffffa:        das
0xffffb:        xor    BYTE PTR [esi],dh
0xffffd:        add    ah,bh
0xfffff:        test   DWORD PTR [eax],0x0
0x100005:       add    BYTE PTR [eax],al
0x100007:       add    BYTE PTR [eax],al
0x100009:       add    BYTE PTR [eax],al

Best regards!
Develop.ReactOS
2007-03-25


             reply	other threads:[~2007-03-25  6:35 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-03-25  6:35 Develop.ReactOS [this message]
2007-03-26  5:55 ` David Daney

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