A serial data bus with a two-wire line and a plurality of bus nodes for the exchange of data messages in both directions between the bus nodes and a central unit connected to the bus and for the current supply of the bus nodes. Conflicts between data messages that appear simultaneously are resolved on...http://www.google.com.au/patents/US5928344?utm_source=gb-gplus-sharePatent US5928344 - Serial data bus and use thereof
