Date: Thu, 30 Dec 1999 09:42:06 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender: eliz AT is
To: sl <junk AT bbs DOT darktech DOT org>
cc: djgpp AT delorie DOT com
Subject: Re: VESA 1.2, cannot get current video mode!
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On Wed, 29 Dec 1999, sl wrote:

> 	Using the VESA 1.2 specification (I also double checked using the MS
> DOS interrupt list) I wrote up the following function.. Unfortunately, on my
> system, this call ALWAYS returns regs.h.al=79 instead of regs.h.al=0 which
> would indicate no error has occured.

79 decimal is 4F in hex, which means VESA is unsupported on your
system.

>    regs.x.ax=0x4F03;
>    regs.h.ah=0x4F;
>    regs.h.al=3;

You only need the first line, the other two are redundant.

>    if (regs.h.al!=0x4F)
>      setError(noSupport); //command not supported

This is backwards: you need to say this:

     if (regs.h.al == 0x4F)
       setError(noSupport); //command not supported