Trends in Powertrain Integrated Control and Development of Optimum Microcomputers

Through the rapid evolution of microcomputer capability in the field of automotive electronic fuel injection, a system has recently been developed to integrate powertrain control, unifying engine control and automatic transmission control.

Implementation of advanced control theory is one of the major issues in this field and will benefit greatly from microcomputer performance improvements.

This paper commences with a discussion of the trend toward higher performance requirements in integrated powertrain control, driven by a new concept in control: variable transmission shiftpoint control based on vehicle operating conditions.

The latter portion of the paper describes a new 16-bit dual CPU system for integrated powertrain control. The system achieves an improvement in processing through high-density communication. Software development is also enhanced by separating the functions of the engine-control microcomputer from those of the transmission-control microcomputer and by using mutually non-interfering software.