Page 55 - The Art of Designing Embedded Systems

42 THE ART OF DESIGNING EMBEDDED SYSTEMS

To put this in another context, getting a 1OOK LOC program to market
65% faster means we’ve saved over 200 man-months of development
(using the fastest of Bell Lab’s production rates), or something like $2
million.
Don’t believe me? Cut the numbers by a factor of 10. That’s still
$200,000 in engineering that does not have to get amortized into the cost
of the product. The product also gets to market much, much faster, and ide-
ally it generates substantially more sales revenue.
The goal is to flatten the curve of complexity. Figure 3-2 shows the
relative growth rates of effort-normalized to program size-for both ap-
proaches.

One CPU

Multiple CPUs

5000 10000 20000 50000 100000 200000
Lines of Code
FIGURE 3-2 Flattening the curve of complexity growth.

NRE versus COGS
Nonrecurring engineering costs (NRE costs) are the bane of
most technology managers’ lives. NRE is that cost associated with
developing a product. Its converse is the cost of goods sold (COGS),
a.k.a. recurring costs.
NRE costs are amortized over the life of a product in fact or in
reality. Mature companies carefully compute the amount of engi-
neering in the product-a car maker, for instance, might spend a bil-
lion bucks engineering a new model with a lifespan of a million
units sold; in this case the cost of the car goes up by $1000 to pay for