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From: "???" <xeneve@yahoo.com>
Subject: VIDEO MEMORY ACCESS WITH POINTERS
Date: 1999/11/27
Message-ID: <81p3sh$h2m$1@news.colba.net>#1/1
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Organization: ColbaNet Internet
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Newsgroups: comp.lang.ada
Date: 1999-11-27T17:20:17+00:00
List-Id: <comp.lang.ada>

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.

Does anybody could help me?