Electrical devices command system, single wire bus and smart quad controller arrangement therefor

A multiplex system within a motor vehicle for commanding and monitoring the status of a plurality of electrical devices or elements disposed throughout the vehicle, each of the elements having command terminals for receiving commands in the form of a voltage signal for activating or deactivating each of the elements, one of the command terminals also being used to provide a status indication in the form of a current signal upon being commanded, said system comprising:

• (a) a bi-directional, single wire bus for transmitting voltage signals in a first direction and current signals in a second direction, said bus being routed throughout the vehicle, said voltage and said current signals being derived in said multiplexed system;
• (b) a plurality of smart quad controllers disposed throughout the motor vehicle, each of said plurality of controllers having (1) a single input/output terminal connected by a single wire to a single point along said bus for receiving the transmitted voltage signals from said bus and for sending the current signals to said bus;
• (2) a pair of input power lines connected across a power source of the vehicle;
• (3) a group of four output command lines with one line from the group going to one of the elements disposed throughout the vehicle for commanding ON or OFF the element;
• (4) a group of four status lines with one line from the group going to a corresponding one of the elements;
• and (5) means for a preprogrammed identifying address of the elements;
• each of said plurality of controllers providing command signals to a group of four elements for turning ON or OFF an individual element of said group;
• each of said plurality of controllers receiving in response to the command signal, a current signal indicative of the status of a commanded element;
• (c) a driver and receiver means connected to the power source of the vehicle and a terminal of said single-wire bus for generating an undulating voltage signal containing a series of dual-duty cycle voltages forming the address and command information of which a first portion of the address information is used to address one of said plurality of controllers, one of said plurality of controllers being addressed if the first portion of the address information matches the predetermined address, and of which a second portion of the address information is used to enable an addressed controller to command the operation of one element of said group of elements connected thereto;
• said undulatory voltage signal being driven onto said bus and into each of said plurality of controllers by said driver and receiver means, said driver and receiver means also having means for receiving from said bus the current signals sent over said bus by each of said addressed controllers indicative of the status of the commanded element;
• (d) display means for displaying the status of the plurality of elements;
• and
• (e) a microcomputer means interconnecting said driver and receiver means and display means for (1) writing logic commands to said driver and receiver means for controlling the generation of the undulatory voltage used to develop the address and command signals placed on said bus for addressing and commanding each of said plurality of controllers in order to cause each of said plurality of controllers to operate the group of elements connected thereto, (2) reading signals indicative of the status of the command element that is sent by said addressed controller, (3) establishing a history of performance of each of the commanded elements and, (4) transferring updated status information to said display means.