外文原文：Microprocessors in EngineersThe development of the microprocessor during the 1970s brought about a revolution in engineering design. The industrial revolution at the turn of the nineteenth century heralded the development of the machines which could replace physical drudgery by mechanical means. Apart from a few exceptions, however, these machines required manual supervision because the problem of controlling this mechanical power was not at all straightforward.Many types of automatic control systems have appeared during the twentieth century, based on electronic, mechanical, hydraulic and fluidic principles. In each case the design techniques have been similar because each component of the system usually contributes a single well defined function to the system behavior.The microprocessor represents a fundamentally different approach to the design of a system. Its physical form is quite simple and reliable, consisting of a few general-purpose elements which can be programmed to make the system function as required. It is the controlling program which must be designed to give the system the required behavior, and which will contain “components” and “subassemblies” just like any other kind of engineering. The program, or software, is just of the engineered system as the physical hardware, but it is much less susceptible to failure, provided that it is designed properly.The idea of programmed systems is not new; electronic computers have been in existence for many decades. However, it has taken the development of the large scale integrated circuit-the silicon chip-to produce computers which are cheap, rugged, and reliable enough to be incorporated into engineering designs as components. The techniques o...
