Re: Embedded Processor/Compiler Selection

[Rakesh Malhotra <rakesh.malhotra@safetran.com>]

Marin David Condic, 561.796.8997, M/S 731-96 wrote:
> 
> Roger Racine[SMTP:rracine@draper.com] writes:
> |One of Draper Laboratory's first Ada projects was an engine controller.
[delelted text]
>     some experiments with this in our real time world to see how much
>     better it is. But that means getting an Ada95 compiler for some
>     sort of inexpensive SBC, and I despair of seeing this happen) But
>     at really high cycle rates, you often can't afford to waste any
>     time, so you go with the simplest possible implementation.

We too develop custom hardware here (our market is embedded, real-time,
safety critical rail-road stuff)- in the past this has been boards based
on the Motorola 68302, 68332 and 68EC030.  All these were done in Ada83.

We are starting a new project, and for this I have been looking at using
the PowerPC EC603e, 166MHz/200MHz.   We have not actually started the
project and so I cannot provide you with much info other than just what
I have researched.  I did look into SBC's/ Ada compilers and there are a
few vendors out there selling SBCs (PowerPC) for $1500 to about $5000. 
Do not know if this expensive for you.   I guess the Ada95 compiler
environment would be expensive - though if you just wanted to do a bunch
of benchmarks you could probably convince a vendor to "loan" you a
license for a month.

The other thing I looked into was using Linux on PowerPC.  There is a
port of Linux/ PowerPC available and GNAT may run on it.  Have not
investigated this yet. I understand that Linux is far from real-time but
if you have an in-circuit emulator you may be able to do benchmarking by
setting up address ranges (though you would need an ICE for your
processor).

In the past I have used Alsys and Rational Ada83 compilers.  The Alsys
compiler comes with a run-time called SMART which is a cut down, bare
bones runtime - it does not support tasking/heap allocation etc. 
However since we use a tool called SPARK (for static analysis of our
software) and this tool does not allow the use of more esoteric Ada
features anyway, it does not really matter.   I have had very good
results with SMART.

More recently we used Rational (VADS) and this too has an optional
runtime that is fairly cut down -- have not had many problems.

Note: as an aside I was amazed to find that a PowerPC running at 133MHz,
giving well over 100MIPS costs just $25/- and dissipates of the order of
only 4W !!
--
Rakesh