Automatic software production for microcomputers

Abstract

The low cost and small size of microcomputers enable the benefits of stored program computer techniques to be applied to small applications such as self-contained instruments using complex logical functions. With low hardware costs, however, the costs of programming and debugging become very significant (the complete microcomputer may only cost the equivalent of one or two man-days of design time). Therefore, techniques must be found which reduce expensive design time and debugging effort.

As part of our general research effort into software reliability we have investigated the use of decision tables and methods for their automatic preparation. Decision tables are a compact form of specifying a program's logical function to a computer which can be directly and simply interpreted by the computer. The tables can be automatically and reliably generated from several forms of logical function specification.

Using these techniques microcomputer-based designs can be produced very quickly and, almost as important, modified quickly without introducing extra errors during modification. The basic design remains constant for different applications, only the specification of function, in the form of the decision table, changes. Thus the software part of the design can be regarded as using off-the-shelf components in the same way as microcomputer hardware design is approached.