Practical Design Considerations

Abstract

In system design a good starting point is to regard the system as a black box. The purpose of the black box is to accept certain inputs, process them, and then to produce certain outputs. In this sense the system performs a function, similar to the case where g(x) is a function of x in mathematical analysis. Some initial specifications are literally a listing of inputs on the left side of a sheet of paper, and the corresponding outputs on the right side. Or perhaps a collection of waveform-timing diagrams are to be realised. At this stage one should not be concerned with the mass of detail that will follow later. The important thing is to get the functional description right.