Message-ID: <34F3B710.7E67@post.comstar.ru>
Date: Wed, 25 Feb 1998 09:15:44 +0300
From: Dim Zegebart <zager AT post DOT comstar DOT ru>
Reply-To: zager AT post DOT comstar DOT ru
Organization: Comstar Ltd.
MIME-Version: 1.0
To: JAP <jap AT mundivia DOT es>
CC: DJGPP Mail List <djgpp AT delorie DOT com>
Subject: Re: Xpressions
References: <6cun1l$qct$1 AT talia DOT mad DOT ibernet DOT es>
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JAP wrote:
> 
> Hi again.
> I don't understand how to compute the segment and the offset from the 32 bit
> address, for example, the __tb buffer in this VESA expression:
> __dpmi_regs regs;
> regs.x.ax=0x4f00;
> regs.x.es=(__tb >> 4) & 0xffff;   /* segment */
> regs.x.di=__tb & 0x0f;    /* offset */
> __dpmi_int(0x10, &regs);
> I don't know what these two expressions mean.
> Thanks.
Look at 'dosmemget' function description.
'>> 4' means shifting four bits right
'& 0x0f' means AND with 15 (15dec==0x0fhex==1111bin)

-- 
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|   \   /   Dim Zegebart
____/____   

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DZcomm - comm library for Allegro
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