Path: utzoo!attcan!uunet!cbmvax!joe
From: joe@cbmvax.UUCP (Joe O'Hara - QA)
Newsgroups: comp.sys.atari.st
Subject: Re: Multitasking on the ST
Message-ID: <7664@cbmvax.UUCP>
Date: 15 Aug 89 04:18:08 GMT
References: <8908021826.AA05333@ucbvax.Berkeley.EDU> <15627@watdragon.waterloo.edu> <1989Aug4.173233.8259@sj.ate.slb.com> <376@eagle.wesleyan.edu> <63138@linus.UUCP> <29201@pbhya.PacBell.COM>
Reply-To: joe@cbmvax.UUCP (Joe O'Hara - QA)
Organization: Commodore Technology, West Chester, PA
Lines: 23

In article <29201@pbhya.PacBell.COM> dbsuther@PacBell.COM (Daniel B. Suthers) writes:
>After reading this a question popped into my head.  If you are downloading in
>the back ground (it seems the most popular multi-task task) and running a 
>action game in the foreground,  do you set the download process to the 
>highest priority to avoid losing data or do you just put up with longer
>download times and connect times so your joy-stick will be responsive?

Believe it or not, the answer is neither. The actual I/O is processed by
device drivers, in these examples the serial device and the gameport
device. The drivers have higher-than-standard priorities. In the download
situation, received characters are stored in a buffer until the application
program gains control and "reads" them (burst them into the program). The
joy-stick action results in events which are passed to the game program as
messages. Consequently, the game program could be given higher priority if
you wished without a noticeable degradation of the teleprocessing task. The
serial device buffer can range from 512 - 16,000 bytes (user controlled).
-- 
========================================================================
  Joe O'Hara                ||  Comments represent my own opinions,
  Commodore Electronics Ltd ||  not my employers. Any similarity to
  Software QA               ||  to any other opinions, living or dead,
                            ||  is purely coincidental.
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