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

• US 4,908,822 A
• Filed: 12/07/1988
• Issued: 03/13/1990
• Est. Priority Date: 12/07/1988
• Status: Expired due to Fees

• Current Assignee: Chrysler Motors Corp (Stellantis NV)
• Original Assignee: Chrysler Motors Corp (Stellantis NV)
• Inventors: Wroblewski, Thomas R.
• Primary Examiner(s): Olms, Douglas W.
• Application Number:
  US07/280,916
• Time in Patent Office: 461 Days
• Field of Search: 370/85, 370/94, 370/89, 370/96, 370/90, 370/24, 340/825.5, 340/825.51, 340/825.52, 340/425.5
• US Class Current: 370/276
• CPC Class Codes: B60R 16/0315 using multiplexing techniques multiplexing for transmission of signals G08C15/00; multiplexing for electrical communication in general H04J
• CPC Class Codes: H04J 3/26 in which the information and the address are simultaneously transmitted
• CPC Class Codes: H04L 12/40 Bus networks
• CPC Class Codes: H04L 12/40013 Details regarding a bus controller
• CPC Class Codes: H04L 2012/40273 the transportation system being a vehicle
• CPC Class Codes: H04Q 9/14 Calling by using pulses

Abstract

A multiplex system for addressing, commanding and monitoring the status of a plurality of electrical devices disposed throughout a motor vehicle. A dual-duty cycle type voltage waveform generated by a microcomputer provides a series of address information signals for enabling individual dual controllers connected to a bi-directional single wire bus coupled at one end to a driver and receiver circuit of the microcomputer. After the individual dual controller is addressed, another portion of the waveform enable the addressed controller to use a voltage signal to operate one of the connected pair of elements. Then, another portion of the waveform provides a binary bit used by the addressed controller for establishing the polarity of the command voltage to turn ON and OFF the addressed control element. Circuit within the addressed controller provide current signals indicative of the status of the commanded element.

Claims

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

(a) a bi-directional, single wire bus for transmitting in a first direction a series of square wave, double duty cycle, voltage signals used for commanding ON or OFF the plurality of elements and a series of current signals transmitted in a second direction used for indicating the ON and OFF status of the plurality of elements;

(b) a plurality of smart dual controllers disposed throughout the motor vehicle, each one of said dual controllers being disposed near a pair of elements for commanding ON or OFF one of the pair of elements, each of said dual controllers having;

(1) a single input/output terminal connected by a single wire to a single point along said bus for receiving the square-wave voltage signals from said bus and;

(2) integration means for converting the square-wave voltage signal into a dual-amplitude, sawtooth-pulse waveform containing address and data information wherein a first amplitude pulse represents LOW bits and a second amplitude pulse represents HIGH bits;

(3) detection means for detecting a first portion of an address code from said sawtooth-pulse waveform in order to enable said dual controller to command one of the pair of elements when the detected address code matches a preprogrammed address of said dual controller, said detection means also including means for detecting a second portion of the address code used for selecting which one of the pair elements to command ON or OFF;

(4) means for detecting a data bit code from said sawtooth pulse waveform in order to determine whether to turn ON or OFF the selected element;

(5) means for commanding the selected element ON or OFF, said commanding means including means for transmitting a current signal back over said bus indicative of the status of the element after commanding the element ON or OFF;

(c) a driver and receiver means, receiving power from a power source of the vehicle and connected to said single-wire bus, for generating the series of square-wave, double-duty cycle voltage signals used by each of said dual controllers, said driver and receiver means also including means for receiving the status of the elements indicating current signals transmitted over said bus;

(d) display means for displaying the status of the plurality of elements; and

(e) a microcomputer means interconnecting said driver and receiver means and said display means for (1) writing logic commands to said driver and receiver means for controlling the generating of the series of square-wave, double-duty cycle voltage signals used for placing address and command information on said bus, (2) reading the current signals indicative of the status of the commanded element;

(3) establishing a history of performance of each of the commanded elements; and

(4) transferring updated status information to said display means.

2. Apparatus in accordance with claim 1 wherein each of the series of square-wave voltage signals contain five independent duty-cycle, address pulse signals and a data pulse signal, four of the address pulses being used to address one of said dual controllers by matching the predetermined address fixedly assigned to each controller and the fifth address pulse being used to enable an addressed dual controller to command ON or OFF, with a voltage signal, one of the pair of elements and the data pulse being used to determine the polarity of the command voltage signal going to the addressed element.

3. Apparatus in accordance with claim 2 wherein said dual controller includes (1) means for converting said address and command pulses into address and command binary bits, (2) means for detecting said address and data bits, (3) means for providing an acknowledgement to said microcomputer of the addressing of said dual controller, (4) means for commanding one of the pair of elements ON or OFF in response to the polarity of the detected data bit, and (5) means for detecting a status indicating current signal from the commanded element and then transmitting the current signal over said bus to said driver and receiver means.

4. In a vehicle multiplex system for both controlling and monitoring the status of a plurality of electrical devices or elements disposed throughout the motor vehicle, the elements containing control and status indication terminals, the system comprising:

a. microcomputer means having a predetermined program which controls addressing, commanding and monitoring the system and which produces therefrom a series of logic signals from at least a pair of output ports that represent the address and command information needed for operating the plurality of elements;

b. driver and receiver means adapted to receive the series of logic signals from said microcomputer means and to selectively convert the series of input logic signals into a series of dual-duty cycle output voltage signals of a chosen format containing address and data information needed to operate the plurality of elements;

c. a bi-directional, single wire bus connected to the driver and receiver means at one end for transmitting the voltage signals in a first direction needed to operate each of the plurality of elements and for transmitting status information concerning the operated element after the element had been operated in the form of a current signal from the element in a second direction, said bus being routed throughout the vehicle, and

d. a plurality of dual controllers, each of which having connections from an output end to a pair of the plurality of elements so as to permit commanding ON or OFF the connected pair of elements and to permit obtaining a current signal from the connected elements indicative of the operational status, each of said plurality of controllers having means for (a) forming a single point input connection with said bus and for (b) forming a power connection across a vehicle battery to receive battery power.

5. Apparatus in accordance with claim 4 wherein said microcomputer means includes means for reading the status information of each commanded element transferred by each of said dual controllers, and wherein said microcomputer means also includes means for transferring the status information to said display means for display.