Execution-Time Analysis of Process Control Algorithms on Microprocessors

One of the basic problems in the area of microprocessor-based process control is the estimation of execution time and storage required to implement a given control algorithm on a specified microprocessor. With improvements in the capability of microprocessors and increases, in sophistication and cost of control software higher level languages particularly, Pascal is becoming popular in control applications. In this paper, a methodology is suggested for estimating the execution-time bound and storage requirements of control algorithms coded in Pascal when they are run on a specified microprocessor. The method consists of some modifications of the Pascal P-compiler, which yields the P-code and together with it a subsidiary sequential file of records to facilitate timing and storage calculation. This sequential file, together with the parameters used in program loops in the PASCAL application program and P-code instruction execution time and code size for a specified microprocessor, yields the execution-time bound and memory requirements. Using this methodology, the performance of a set of recently announced 16-bit microprocessors in some control applications is evaluated.