Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!cernvax!chx400!bernina!stp
From: stp@bernina.ethz.ch (Stephan Paschedag)
Newsgroups: comp.realtime
Subject: Re: Is polling possible with OS9000 device drivers
Message-ID: <1991Jan20.131236.1015@bernina.ethz.ch>
Date: 20 Jan 91 13:12:36 GMT
References: <1991Jan16.174652.10867@computing-maths.cardiff.ac.uk>
Reply-To: stp@bernina.UUCP (Stephan Paschedag)
Organization: Swiss Federal Institute of Technology (ETH), Zuerich
Lines: 28

In article <1991Jan16.174652.10867@computing-maths.cardiff.ac.uk> rhl@computing-maths.cardiff.ac.uk (Robert Hartill) writes:
>Sorry to OS9 newsgroup readers if this is the wrong place to ask.. is there
>A friend of mine who is new to OS9000 wants to write a device driver for a
>programmable I/O controler which does not raise an interrupt on the host PC.
>
>He says that OS9000 doesn't directly support device drivers that poll devices.
>He's come up with some sort of solution which he is not entirely happy with.
>
>Sorry I can't give any more details than this,
>Any comments ?

I think there are two ways for a solution :

  -  use system state alarms for polling (polling speed is limited to tickrate)

  -  use an external timer for generating the polling frequency (the timer must
     support interrupts).

good luck !

Stephan

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OS/2 & PS/2 : half an operating system for half a computer

Stephan Paschedag                                         stp@ethz.UUCP
MPL AG, Zelgweg 12, CH-5405 Baden-Daettwil     ..!mcvax!cernvax!chx400!ethz!stp
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