Re: Ada for microcontroller?

["Will Deatrick" <will_deatrick@smtp.ESL.COM>]

 RE>Ada for microcontroller?
In <1993Jul23.123338.26421@hellgate.utah.edu>, Mark Atwood writes:

> I'm starting on a new project that will be running
> on an embedded controller. Looking through the list
> of Validated Ada compilers, I noticed that there
> were several for the MIL-STD-1750 processor.
> If someone could fit Ada onto that (begin personal
> opinion) clunky, obsolete at birth, small, slow, expensive
> piece of **** (end personal opinion) why not for a 8051,
> 6805/08/11. Z80, etc., based microprocessor?

About a year ago, I ran into this same problem on a DoD program. We planned to
use a small, cheap 8031 as a Built-In Test (BIT) controller. The processor had
to be small and cheap since it would be present on every hardware module, but I
could not find an Ada compiler for the 8031.  I got several responses to my
queries on comp.lang.ada and by talking to vendors, and the explanations for
the lack of Ada compilers for these processors included:

1) Getting all of the Ada language to run in the 8 or 16-bit address
   limitations typical of smaller processors is difficult.

2) Even though many of the advanced constructs (tasking, generics) may not be
needed 
   for a small application, you can't pass the ACVC tests without them and no
one
   wants a non-validated Ada compiler.

3) It is possible to get an exception to write a small amount of code in
another
   language, even on DoD programs.

4) If the processor and the code are small, then hardware availability down the
   road becomes a more important issue than software maintenance costs.

5) The market for Ada on small processors is not large enough to justify the
expense.

Someone did mention the MC68302 series microcontroller as a possibility as it
had a low chip count and an Ada compiler.  I did not get any farther in my
search as that part of the program was cut.  Unless things have changed within
the last year, you may be forced to start brushing up on your C and assembly.
:-)

Regards,

Will Deatrick
deatrick@sdfvax.rc.trw.com