Automotive companies are presently designing microprocessor based electronic products. The cost effectiveness of large scale integrated (LSI) microcomputers makes possible the design of sophisticated, yet economical engine controls. To effectively utilize microcomputer technology, automotive product designers need to learn new engineering disciplines, including microcomputer software. Understanding how to evaluate hardware versus software tradeoffs to develop a minimum component count system that has the flexibility to incorporate changes, is a fundamental requirement for a high volume production design. An example is a microcomputer digital spark timing control unit that can be programmed during assembly to match engine specifications for four, six, or eight-cylinder engines.