Microprocessor Implementation of PID Controllers and Lead-Lag Compensators

This paper discusses the microprocessor implementation of two widely used industrial controllers: the PID controller and the Lead-Lag compensator. The main characteristics of this implementation are the general form of the equations used, the high precision maintained, and the capability of handling a wide range of numbers by means of floating point representation in the microprocessor. An 8-bit general purpose microprocessor is employed, and the entire hardware and software required for the floating point arithmetic simulation and the controller's realization are presented. The flexibility of the proposed design is also discussed. The material presented in this paper may be useful to control engineers interested in microprocessor-based control, as well as to microprocessor/computer specialists interested in applications to the control field.