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From: rg@msel.unh.edu (Roger Gonzalez)
Newsgroups: comp.sys.ibm.pc.misc
Subject: Direct address access via C
Message-ID: <1991Jan28.202900.11946@unhd.unh.edu>
Date: 28 Jan 91 20:29:00 GMT
Sender: news@unhd.unh.edu (USENET News System)
Distribution: comp
Organization: UNH Marine Systems Engineering Laboratory
Lines: 18

I'd like to directly manipulate the text video area via Turbo C.  I gather
that it is located at B something or 8 something, depending on your adaptor.
How do you do the memory access, though?  On a VMEbus based machine, all 
you have to do is coerce a pointer to be the address, and then you can do
stuff like overlay structures on the memory map.  I'm new to this aspect
of PC programming, since I'm mainly a Unix programmer.

Is there any speed gain in doing C->addr manipulations rather than using
Turbo's (a little too restrictive) routines, or do I have to learn Intel's
assembler to really get anything out of it?

-Roger

-- 
"The question of whether a computer can think is no more interesting
 than the question of whether a submarine can swim" - Edsgar W. Dijkstra 
rg@[msel|unhd].unh.edu        |  UNH Marine Systems Engineering Laboratory
r_gonzalez@unhh.bitnet        |  Durham, NH  03824-3525