Factors affecting commercial computers system design in the seventies

The design of a digital computer for the commercial market today must, of course, face up to the pervasive influence of IBM. But technological maturity in some areas is slowing the rate of change so that designs seem to converge on certain features. Microprogramming of the native instruction set (or sets?) with emulation of a range of older systems is such a feature. Virtual memory addressing may be another. Characteristics of main storage, random access mass storage devices, data exchange media seem to converge while terminals and communications conventions proliferate and diverge. Some reasons for these phenomena are evident; others will be suggested.

Whatever happened to hybrid packaging, thin films, large scale integration, and tunnel diodes? The more general question is: why do some technologies flourish only in restricted environments, or never quite fulfill the promise of their "youth?" Or is their development just slower than we expected? While these answers cannot be absolute, some factors affecting the acceptance of new technologies can be identified.