From:	"John M. Aldrich" <fighteer AT cs DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Char blitting
Date:	Fri, 16 Jan 1998 19:41:09 -0500
Organization:	Two pounds of chaos and a pinch of salt.
Lines:	32
Message-ID:	<34BFFE25.192C@cs.com>
References:	<19980116194601 DOT OAA28275 AT ladder02 DOT news DOT aol DOT com>
NNTP-Posting-Host:	ppp247.cs.com
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

HackerOC3 wrote:
> 
> I am using a function to blit chars and strings to the screen.  Below is the
> version that blits chars.  It crashes my computer.  I think it may have
> something to do with the base
> address for the ASCII chars, 0xF000FA6EL.

[snip]

> //Compute the starting offset in the ROM character look - up table.
> 
> *work_char = (unsigned char)0xF000FA6EL + c * CHAR_HEIGHT);

Of course this won't work.  You're trying to access an absolute address
in conventional memory from a protected mode program.  You're also using
an illegal addressing method; remember that DJGPP is not Turbo C.

The equivalent protected mode address would be 0xffa6e, and you can
access it by using the _farpeekX() functions just like you use
_farpokeX() to access video memory.  For more information, see chapter
18 of the Frequently Asked Questions list (v2/faq210b.zip from SimTel or
online at http://www.delorie.com/djgpp/v2faq/).

hth

-- 
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|      John M. Aldrich       | "A committee is a life form with six |
|       aka Fighteer I       | or more legs and no brain."          |
|   mailto:fighteer AT cs DOT com   |                                      |
| http://www.cs.com/fighteer |                 - Lazarus Long       |
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