Re: understanding runtime support

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

Patrick,

As I said before, "embedded" means many different things.  The
cheapest and easiest solution is Debian for ARM, it comes with
everything you need, precompiled and ready to go.  Don't be sad that
it contains a Linux kernel and a glibc written in C.  As for
controlling a purpose-built device, it is quite possible that this
purpose-built device can run Debian ARM.  After all, the Raspberry Pi
comes very close to what you need and it runs Debian ARM.  Also, a
purpose-built device might not be the most appropriate solution,
maybe (just maybe) an app running on a smartphone might be better.

If you insist on programming the bare metal in Ada but are a one-man
company with no prior experience, then yes you are being unreasonable.
As Randy pointed out, this is a *very* time-consuming endeavor even
if you start from the GNAT sources.  But it is doable and it has been
done before (I remember writing the firmware for avionics devices in
Ada, programming to the bare metal.  The Ada run-time did not support
tasking or memory deallocation, and could not propagate exceptions
beyond the frame that raised them.  We "just" lived with these
constraints).

I encourage anyone with enough time and expertise to donate some and
send me the patches necessary to support GNAT as a cross-compiler
with Debian as the host and whatever strikes your fancy as the target.
(While I'm at it, I feel I can pre-announce the availability of GNAT
on Debian armhf, thanks to the hard work of Tero Koskinen.  Stay
tuned for the official announcement.)

-- 
Ludovic Brenta.