BB Converter

As with human languages, many ways were devised to allow the computers and devices to communicate and, as with their human counterpart, most of the communication is incompatible with any of the other systems. The incompatibility can be broken into two categories: the physical layer and the protocol layer What is an industrial bus? Traditionally, the industrial bus has been used to allow a central computer to communicate with a field device. The central computer was a mainframe or a mini (PDP11) and the field device could be a discreet device such as a flow meter, or temperature transmitter or a complex device such as a CNC cell or robot. As the cost of computing power came down, the industrial bus allowed computers to communicate with each other to coordinate industrial production.The physical layer and the protocol layer can be defined using the phone system as an example. Any spoken language can be carried over a phone line. As long as both the speaker and the listener(s) understand the language, communication is possible. The phone line is not concerned with the meaning of the signal that it carries, it is merely moving those signals from one point to another physically. This is the physical layer, the conduit in which communications pass from one point to another. On the other hand, the speaker and listener(s) are concerned with what is transported over the phone line. If the speaker is talking in Spanish and the listener(s) are only fluent in English, communication is not possible. Although the physical layer is working, the language or "protocol" is not correct, and communications cannot exist. The industrial world has developed a variety of different physical and protocol communications standards.