Microprogram control for the experimental sciences

In many areas of the experimental sciences, increasing use is being made of general-purpose computers to control experimental apparatus and to record data from experiments. In most such applications the problem exists of connecting the apparatus to the computer so that data and control information may flow between the two. The problem is usually solved by placing a controller between the computer and the external equipment (Fig. 1). In this position the controller serves two functions: (a) It provides a suitable electrical and logical interface between the computer and the external equipment; and (b) It provides detailed control of the external equipment, thus leaving the computer free for other work.