PROFIBUS communicates via a serial protocol behind which complex machinery is housed to transport the data reliably through an industrial environment. The protocol defines the message design, the access to the network and fault control. There are ASICs (chips) available that coordinate the entire protocol. This way, the product developer does not have to be involved much in PROFIBUS to build a field instrument.communicates via a serial protocol behind which complex machinery is housed to transport the data reliably through an industrial environment. The protocol defines the message design, the access to the network and fault control. There are ASICs (chips) available that coordinate the entire protocol. This way, the product developer does not have to be involved much in PROFIBUS to build a field instrument.