Patent ID: 7206885

Claim:
A system for connecting a mobile data unit to a field bus, comprising: a coupling unit connected to the field bus via a spur line and a line driver, wherein signals at an output of the line driver are injected via a first level converter in the coupling unit into a first data link or are received from the first data link; a mobile data unit receiving the signals via a first level converter in the mobile data unit from the first data link or injecting the signals into the first data link; the first data link connected to the first level converter in the coupling unit via an electrical jack for communicating data between the mobile data unit and the field bus; a presence detection circuit comprising a digital signal line providing a presence signal responsive to coupling of the mobile data unit to the coupling unit; and a local controller connected to the field bus and connected to the presence detection circuit for receiving the presence signal, wherein the local controller can transmit a selection of views to the mobile data unit via the digital signal line.