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From:	peprbv AT cfa0 DOT harvard DOT edu (Bob Babcock)
Subject:	Re: Help with vid mem access, please.
Sender:	news AT cfanews DOT harvard DOT edu
Reply-To:	rbabcock AT cfa DOT harvard DOT edu
Organization:	Smithsonian Astrophysical Observatory, Cambridge, MA, USA
References:	<jstev DOT 812761647 AT ccserver>
Date:	Wed, 4 Oct 1995 04:53:29 GMT
Lines:	19
To:	djgpp AT sun DOT soe DOT clarkson DOT edu
Dj-Gateway:	from newsgroup comp.os.msdos.djgpp

Joshua Bates Stevens (jstev AT ccserver DOT uoregon DOT edu) wrote:

: Could someone please post a short code fragment showing how to directly 
: access video memory from djgpp *without* using inline assembly?  I'd be 
: very grateful.

Here's a fragment which displays a single character and attribute at
screen position Screen.  (Screen = 160*row+2*col for 80 char wide screen
assuming 0-based row and col numbers.)

#include <sys/farptr.h>
#define MK_DOS_ADDRESS(seg,ofs) (((unsigned long)(seg) << 4) + (unsigned)(ofs))
	_farsetsel(_dos_ds);
	screen = MK_DOS_ADDRESS(Screen_seg, Screen);
	_farnspokeb(screen, chr);
	_farnspokeb(screen+1, attr);

However, the farptr routines expand to inline assembly, so maybe this
doesn't fit your request.

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