OBJECT LIST CONTROLLED PROCESS DATA SYSTEM

摘要

The appropriate design of a system is one of the essential topics at the beginning of a new development project. According to the intended purpose of a device the first step is to model the system in order to get a structure for the implementation of the required features. In general the implementation of the system requirements is split in hardware parts and tasks which are done in software. In case of the hardware design the solutions for the challenges are mostly clear and supported by fundamentals of e.g. digital logic laws and several design methods. If we think of the software part a lot of problems have to be solved without such clear fundamentals. Object oriented design is one of the paradigms which promise a way for designing stable and reliable software. A problem arises in this context if the used microprocessor platform is not supported with a compiler for an object oriented programming language. In this case only the system modelling could be done in terms of software objects and their relations, the implementation has to be done in a procedural language. The following article is based on research work done in the development of a modular process data system. Based on a sequential main program and interrupt driven hardware interfaces, a software implementation without an operating system was implemented. By means of special software structure called Linked Object List, object oriented design was implemented with the procedural language "C". Due to this design a reusable and flexible system was achieved which enables a high degree of flexibility concerning the hardware configuration and system customization at the user site.