Fieldbuses are a group of computer network protocols used mostly in industrial applications. The most common ones were developed in the 1980s to enable simpler connection of complex systems, replacing the formerly necessary individual connection of a system's control component to each sensor and actuator (parallel connection).
By specifying how the interconnected devices communicate with each other and thus enabling a data flow from device to device, it became possible to connect hundreds of devices with just a single bus cable. While this gave the systems self-diagnosis capabilities and in many cases dramatically reduced the cost of cabling, the need for each connected device to have a microprocessor in turn raised the price of individual components.
With the multitude of fieldbus interfaces on the market, new devices are often required to support several fieldbus protocols. MEN has realized rugged interface solutions based on CANopen, DeviceNet, Profibus, MVB, WTB, AFDX®, Arinc, Bitbus, WorldFIP and InterBus-S, implementing these fieldbus functions on M-Modules™ and other mezzanine boards (PMC, PC-MIP® or as a PCI-104 module) as well as on single-board computers and stand-alone devices like box computers and panel PCs. When a specific fieldbus is not provided by the unit's processor directly, it is often implemented as an IP core in an FPGA with an SA-Adapter™ providing the physical layer. This way, many MEN systems offer CAN bus support straight out of the box.
Typical fieldbus applications include industrial automation, medical equipment and vehicles. For example, the popular CAN (Controller Area Network) bus was originally developed by the Robert Bosch GmbH for inter-device communication within a car. IBIS (Integriertes Bordinformationssystem) is the fieldbus standard used in German public transportation while the MVB (Multifunction Vehicle Bus) is commonly used in railway applications, often used in tandem with the WTB (Wire Train Bus). A popular fieldbus commonly used in industrial automation (e.g., processing plants and manufacturing facilities) is Profibus (Professional Field Bus).