NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/sys/amiga/programmer/4009

Internet Message Format | 1996-08-05 | 1.6 KB

Path: mat.uni.torun.pl!not-for-mail
From: [e-mail] (Andrzej Chojnowski)
Newsgroups: comp.sys.amiga.programmer
Subject: System-friendly programming. How?
Date: 15 Feb 1996 17:46:22 GMT
Organization: Uniwersytet Mikolaja Kopernika
Message-ID: <4fvrhe$[e-mail]>
NNTP-Posting-Host: class1.phys.uni.torun.pl
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-2
Content-Transfer-Encoding: 8bit
X-Newsreader: TIN [UNIX 1.3 950824BETA PL0]

Yesterday I sit down & tried to write simple intro. I decided to put module
player routine call in VBLANK interrupt. I want to make it system-friendly.
Okie. I did it. But after intro execution system got crazy. I sit down once
again & found out what was the cause of such nasty effects: the player routine
It uses the CIA-A timer B which is used probably by the system too. So I got
some questions:

1) Is there any way to allocate/deallocate each CIA timer?
2) Is there any player routine which don't need CIA timers to run?
   (I have 3 different routines: pt-play.s, pt-ciaplay.s, ptplay30b.s)

Another problem appeared when I opened a 32-colour screen. I don't know how
to get rid of arrow pointer WITHOUT manipulation on DMACon (I said I wanna
be system-friendly :) It should be possible. I thought that setting the
screen's viewport flags to not allow displaying sprites will help. It won't.
Any ideas ?? (That silly thing really makes me upset ;)

Last question may sound stupid : How the Amiga multitasks?
Is that a kind of timer interrupt which switches the tasks?
Does calling Disable prevent the task change like Forbid does?

                                                   Andrew.