Patent ID: 6363066
Filing Date: 2002-03-26
Classification: H04B,H04L

Abstract:
Method for combined data and power distribution between nodes in distributed data processing systems having a common communication bus for the nodes containing at least one wire on which digital information is transmitted serially in a form of dominant data bits at a first signal level and recessive data bits at a second lower signal level, which method comprises:selectively transmitting from a first node via the communication bus dominant and recessive bits, the dominant bits from the first node causing at least one wire of the communication bus to assume a first voltage level exceeding a voltage level of the wire during transmission of recessive bits; selectively, transmitting from a second node via the communication bus dominant and recessive bits, the dominant bits from the second node causing the at the least one wire of the communication bus to assume a second voltage level which second voltage level exceeds or is equal to the first voltage level, said first node lacking any separate power supply, while said second node being equipped with a power supply separate from the communication bus; charging a voltage accumulator in the first node by the dominant bits being transmitted on the communication bus from the second node, causing said at least one wire of the communication bus to assume a voltage level corresponding to the second voltage level, thereby providing the first node with power; and detecting with the second node the voltage level on the communication bus and, if a lower voltage level of the dominant bit is detected, then increasing the voltage level of the dominant bit from said first to said second voltage level during at least part of the duration of the dominant bit.