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From: mockturtle <framefritti@gmail.com>
Newsgroups: comp.lang.ada
Subject: Re: How do I write directly to a memory address?
Date: Thu, 3 Feb 2011 00:08:50 -0800 (PST)
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> Below is an
> example of code I would like to be able to implement.
>=20
> ...
> unsigned int print(char *message, unsigned int line)
> {
> 	char *vidmem =3D (char *) 0xb8000;
> 	unsigned int i=3D 0;
>

I do not have any experience about this part of Ada, but maybe I can give y=
ou a "pointer" to some bootstrapping information.  Maybe you could want to =
use an attribute representation  clause for Vidmem'Address (see Section 13.=
3 of the RM) . With some improvisation, I would write something like=20

   type Vidmem_Array is array (natural range <>) of Character;
   Vidmem : Vidmem_Array (0 .. Max_Size);

   for Vidmem'Address use 16#000B_8000#;

Note that  with this approach you need to know the maximum size of your "bu=
ffer".  Otherwise, you could go through System.Address (see 13.7 and follow=
ing of the RM).

As disclaimed above, I am not an expert on this, so maybe someone could wan=
t to integrate/correct/whatever the information above.

  =20
=20
> 	i=3D(line*80*2);
>=20
> 	while(*message!=3D0) // 24h
> 	{
> 		vidmem[i]=3D *message;
> 		*message++;
> 		i++;
> 		vidmem[i]=3D 0x7;
> 		i++;
> 	};
>=20
> 	return(1);
> };
> ...