This paper contributes to the discussions about the development process of Computer Based System by evaluating development principles common practice for computer hardware. in this domain, the descriptions can be classified into abstraction levels and views. For computer based systems a similar classification can be identified. This helps to define the information required at specific points of the development process. For the support of the development of computer based systems an underlying formal model based on Predicat/Transition nets is defined which can be used for simulation and analysis. The applicability of this approach is shown by a frequently used example.