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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Problem with task component
Date: Wed, 19 Sep 2012 22:48:28 +0100
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Date: 2012-09-19T22:48:28+01:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> You need an open terminate-alternative ("or terminate;") when the
> object containing the task component is about to finalize.
>
> The usual problem is that the terminate-alternative does not live
> together with the delay-alternative and/or else-part, which makes it
> quite a challenge to implement something like a typical "driver"
> component task:

Indeed!

This particular application detects discrete I/O changes (switch
open/close) via an MCP23017 i/o multiplexer on a Raspberry Pi.

Using interrupts is in the next phase, for now I'm just polling by
reading the chip's registers so I must delay & can't use terminate. A
pain.