Re: Ada's Slide To Oblivion ...

["Marin David Condic" <dont.bother.mcondic.auntie.spam@[acm.org>]

Well, that's largely a question of the economics of the situation. Suppose
you are making a controller card for a power generating turbine. You sell
these to Florida Power & Light for backup generators, so your sales numbers
are measured in - oh, what? - thousands? hundreds? - lets say 1000 units. To
design a custom board that might eliminate some parts from an off-the-shelf
board could be quite costly. Figure you've got a whole range of tests to run
on it as well to make sure it won't break in its expected use, etc. That
could be a lot of $$$. What do you get for that compared to a COTS board
that maybe you can buy for $100 in quantities of a few hundred? And compared
to the overall price of the end product, its a pretty small item to
optimize. Plus all the headaches of managing the design & manufacture of a
new board and all the risks that go with it. Its probably better to buy one
than attempt to save the cost of the few extra parts you may not need.

Now compare those economics to something that, say, might be more of a
consumer product. Say you're making a microwave oven and plan on selling
them on the order of 1,000,000 units over the life of the design. Suddenly,
some time spent to custom design a board (perhaps based on a COTS-SBC that
you use for development and prototyping) starts making sense. If you can
eliminate $1.00 worth of parts from the board, that saves you $1,000,000 -
which might justify the development and testing costs.

Even for relatively short-run products, it sometimes pays because you might
not be able to get the performance or reliability out of a COTS design that
you need. This is common for rockets because typically you can't buy a COTS
board that would stand up to the extremes of heat, cold and gamma radiation
it has to live through. But that's a rather unusual case. For most shorter
production runs, its going to be more economical to get an SBC that is
reasonably optimized for what you need.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Steve O'Neill" <oneils@gbr.msd.ray.com> wrote in message
news:3C59B1BA.EFCD88C9@gbr.msd.ray.com...
>
> > So what good is an SBC to someone building a rocket ship or a subway ?
> > They aren't really going to build it with SBCs in the production units,
> > are they ?
>
> If they can they will.  The potential cost savings between designing and
> building
> your own hardware and grabbing a commercial board is potentially huge.
> And the
> US DoD has been pushing the use of COTS (Commercial Off-The-Shelf)
> components very
> hard for the past decade.
>