This paper presents a comparative study of two configuration techniques for building cascade control loops in engineering phase by using traditional analog system and modern digital Foundation Fieldbus (FF) system. For both analog and FF systems, control strategy configurations for providing the process control loop with high safety and the process control loop with high availability are described. The engineering software of the CentumVP host system is used to build the studied control systems, and it is also employed to check the consistency of the configurations. Comparison results show that the smart FF devices provide powerful functionalities for ease of engineering to take special actions in the events of undesired conditions. In addition, the results from the studied cases can be the practical guideline to configure the interlocks that are essential for system safety and availability.