If it were necessary for one to master the chemistry and physics

involved in the manufacture of molybdenum-steel piston rings

before one could undertake any sort of automobile repair, there

would be far fewer backyard mechanics in the world. Happily,

this is not the case. After mastering some basic skills and con-

cepts, one need only to consult the appropriate ~how-to-repair"

mandal for the particular automobile involved to affect even

complex repairs. The automobile industry is, of course, a fully

mature one, so there has been time to prepare all types of help-

ful documentation for mechanics as well as automobile engi-

neers. This is not the case with the emerging and dynamic field

of microcomputer-based electronic equipment maintenance.

.~ As I write this, the basic ~cpu-on-a-chip" has only been

commercially available for slightly longer than a decade; its low

cost, flexibility, and tiny size have already enabled true com-

puter power to be added to even such banal applications as the

kitchen toaster, while at the same time a vast variety of so-

phisticated electronic products have become part of our daily

lives. Why then, do almost all books written on the subject of

microcomputer technology still treat the matter as one for re-

search scientists and design engineers?