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From: "Vinzent Hoefler" <0439279208b62c95f1880bf0f8776eeb@t-domaingrabbing.de>
Newsgroups: comp.lang.ada
Subject: Re: How do I write directly to a memory address?
Date: Tue, 08 Feb 2011 22:07:01 +0100
Message-ID: <op.vqlrlzxolzeukk@jellix.jlfencey.com>
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Yannick Duch=C3=AAne (Hibou57) wrote:

> Le Thu, 03 Feb 2011 09:08:50 +0100, mockturtle <framefritti@gmail.com>=
 a
> =C3=A9crit:
>
>>    type Vidmem_Array is array (natural range <>) of Character;
>>    Vidmem : Vidmem_Array (0 .. Max_Size);
>>
>>    for Vidmem'Address use 16#000B_8000#;
>
> There may be a real issue here. This was segment register =3D B800 and=

> offset register =3D 0000, for the base address. Ada does not make any
> distinction about segment and offset.

So it should map the linear address - if possible at all.

> There should be something stated in
> the compiler's documentation, to know how it maps linear address to
> segment:offset address.

Technically there's only one address, even if there are several ways to
address it. It's never been a real issue unless you were comparing
addresses, but even then they were usually normalized before doing so.


Vinzent.

-- =

You know, we're sitting on four million pounds of fuel, one nuclear weap=
on,
and a thing that has 270,000 moving parts built by the lowest bidder.
Makes you feel good, doesn't it?
   --  Rockhound, "Armageddon"