Re: [Q] Is anyone programming DSPs in Ada?

[Markus Kuhn <Markus.Kuhn@cl.cam.ac.uk>]

skulski@nsvs33.nsrl.rochester.edu wrote:
>   I am looking for info on programming DSP processors in Ada.
> In particular, I would like to know if anybody has considered
> programming Analog Devices ADSP 2181 and/or similar chips.
> If not, has anybody an idea what would it take to program these chips
> in Ada?

Someone who developed an anti-tank missle in Germany told me that
they used 12 Analog Devices SHARC DSPs for the radar pattern recognicion
in the missle head, and they were programmed almost completely
in Ada using an (I think) Intermetrics compiler. They changed the
compiler provider once during the development cycle, and they were very
pleased with Ada's portability: The compiler change required only
one day of work, most of it spent with reading the manuals of the
new compiler. It also seems to be a big advantage of Ada on DSPs
(which is a niche market), that the ACVS ensures a quite consistently
high quality of the compilers, while the C compilers for the same
processors are often incompletely implemented with many unexpected
restrictions. The downside is that Ada compilers for DSPs are often
so expensive that only defense contractors can afford them
(80 000 DEM/year = 47 000 USD/year was one figure I remember
from this discussion for the cost of compiler plus support).

Another detail advantage of Ada over C on DSPs is the "for" command:
Its structure encourages a loop programming style that is easily
mapped by the compiler to the zero-overhead loop mechanisms that
most DSPs have (three registers for loop start/end address
and a counter, no conditional jump instructions).

Markus

-- 
Markus G. Kuhn, Security Group, Computer Lab, Cambridge University, UK
email: mkuhn at acm.org,  home page: <http://www.cl.cam.ac.uk/~mgk25/>