From: billlanam AT california DOT com (Bill Lanam)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: [Q] Inline assembler and mov instructions
Date: Thu, 20 Feb 1997 00:36:06 GMT
Message-ID: <330b9890.9518282@seashell.california.com>
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To: djgpp AT delorie DOT com
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On Wed, 19 Feb 97 13:58:43 GMT, johne AT parallax DOT co DOT uk (John Eccleston) wrote:

>Hi All,
>
>I am trying to write some inline assembler to get the address of the
>bios fonts, and I was trying to use MOV instructions like so:
>
>    asm("movw %edx, %bh\n\t");
>
>I use edx as in the extended syntax it is used to pass in a value,
>but the BIOS call requires that the value be in bh.
>
Since you appear to be moving from a large register to a small one you can do

asm ("mov %dl, %bh\n\t\t");

unless you are moving from the esi or edi registers in which case you can do

asm ("mov %si, %bx\n\t\tmov %bl, %bh\n\t\t");

    Bill Lanam