ABSTRACT
Development in communications and networking, systems engineering, and integration, along with development of new applications engineering techniques, has also played an important role in supporting this trend. Layered system architecture brings along advantages associated with distributed processing and allows access to data collected at the lowest levels of the systems hierarchy. The popularity of lower level industrial networks can be explained by the desire to provide more cost-effective solutions for systems implementation and more processing power on the lower levels of the network. Transmission is standardized on a standard serial RS-485 communication over a pair of twisted shielded wires. Actuator sensor interface protocol was developed to interface devices on the lowest level on the system architecture, on the sensor/actuator level. The network topology can be point-to-point, in a star-like configuration, for analog, and combined analog and digital transmission or multidrop topology for digital only transmission.
