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From: Gautier <Gautier.deMontmollin@maths.unine.ch>
Subject: Re: VIDEO MEMORY ACCESS WITH POINTERS
Date: 1999/11/30
Message-ID: <3843A999.FC8C4ABE@maths.unine.ch>#1/1
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Reply-To: Gautier.deMontmollin@maths.unine.ch
Newsgroups: comp.lang.ada
Date: 1999-11-30T00:00:00+00:00
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> Simple problem: I want to able to read and write directly into the video
> memory using Ada code. Ex: writting the 16bits value 0x4141 at the address
> 0xb8000000.

> I'm a new user of ADA, in Pascal or C, it's very simple. But with the strong
> protection of Ada, I'm lost. I know the basics of pointers in ADA (called
> access), but I don't know how to directly address the value 0xb800000 to a
> pointer. I've tried to assign the address using Unchecked_Conversion and it
> works. But when I try to read or write the content in memory, a
> constraint_error exception is raisen.

Take a look at SVGA02X4.ZIP

  http://members.xoom.com/gdemont/logiciel/svga02x4.zip

page

  http://members.xoom.com/gdemont/gsoft.htm

HTH

Gautier