Data transmission device, for vehicle control system, has filters coupling data terminal modems to two supply lines, each powered by separate battery, and modem for transfer of data along the lines

摘要

Data transmission and reception is carried out by an ECU (15) over two distinct supply lines in the vehicle, e.g. carrying 12 and 42 volts respectively w.r.t. the vehicle ground. Transfer of data may either occur either directly as a series of bits superimposed on the supply lines, or preferably using a modem (16) coupled to the lines via bandpass filters (18, 19). Power input to the connected modules is via diodes (11, 13) to provide isolation between the differing-potential lines. An Independent claim is included for a method of data transmission in a vehicle using the arrangement of the invention.