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From: Simon Clubley <clubley@remove_me.eisner.decus.org-Earth.UFP>
Newsgroups: comp.lang.ada
Subject: Re: Point a beginner in the right direction? Cheap bare-board to run
 with a RTOS for running ADA
Date: Sun, 7 Jul 2013 10:58:24 +0000 (UTC)
Organization: A noiseless patient Spider
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Date: 2013-07-07T10:58:24+00:00
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On 2013-07-07, Dmitry A. Kazakov <mailbox@dmitry-kazakov.de> wrote:
> On Sun, 7 Jul 2013 02:16:29 -0700 (PDT), Lucretia wrote:
>
>> Why not just buy a small SBC and just target Ada directly on the hardware.
>> You don't have to have an OS at all.
>
> There exist heaters better than a computer performing pointless
> calculations without any I/O.
>

Sorry, Dmitry, but that's so out of touch I don't really know how to
respond so I will just say you don't need a OS to provide I/O services.

You create some routines around the hardware which the rest of your code
can use to talk to the hardware and you structure your I/O support
library so that only the modules needed by the application are actually
linked in.

For the generic I/O support on top of this, you can then use a intermediate
library (in the C world, that could be Newlib for example) or implement the
I/O support in your language (for languages with I/O syntax built in)
or just use your own generic I/O library.

This is the standard approach taken when working with small embedded
systems at bare metal level regardless of language. As Luke said, no
OS needed. How do you think I/O is done on, say, a small AVR or low
end ARM board ?

Simon.

-- 
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Microsoft: Bringing you 1980s technology to a 21st century world