Data transmission method and system therefor

• US 5,659,702 A
• Filed: 09/14/1995
• Issued: 08/19/1997
• Est. Priority Date: 02/15/1993
• Status: Expired due to Fees

• Current Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Original Assignee: Honda Giken Kogyo Kabushiki Kaisha (Honda Motor Company)
• Inventors: Ishii, Jun, Nagatani, Yuji, Hashimoto, Hiroshi
• Primary Examiner(s): Donaghue, Larry D.
• Assistant Examiner(s): Rinehart, Mark H.
• Application Number:
  US08/527,953
• Time in Patent Office: 705 Days
• Field of Search: 395/200.13, 395/200.14, 395/200.16, 395/200.21, 395/200.11, 395/200.15, 395/200.06, 395/200.17, 395/200.1, 395/183.12, 395/184.01 , 395/183.19, 340/825.07, 340/825.6, 340/825.5, 340/825.52, 379/106, 379/107, 364/241.8, 364/940.8, 370/85.1, 370/85.2, 370/85.3, 370/85.4, 370/85.5, 370/85.6, 370/94.1, 370/13, 370/14, 370/15, 370/451
• US Class Current: 709/245
• 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: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04L 1/1657 Implicit acknowledgement of correct or incorrect reception, e.g. with a moving window
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 1/1685 the supervisory signal being transmitted in response to a specific request, e.g. to a polling signal
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/189 Transmission or retransmission of more than one copy of a message
• CPC Class Codes: H04L 12/40013 Details regarding a bus controller
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/4135 using bit-wise arbitration
• CPC Class Codes: H04L 12/417 with deterministic access, e.g. token passing
• CPC Class Codes: H04L 2001/0094 Bus
• CPC Class Codes: H04L 2001/0098 Unequal error protection
• CPC Class Codes: H04L 2012/40273 the transportation system being a vehicle
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks

Abstract

A data transmission system for a vehicle includes a plurality of control systems installed on the vehicle, and a network bus connecting the plurality of control systems with each other for circulating a transmission right through the plurality of control systems to thereby perform transmission of a message between the plurality of control systems. According to a first aspect, each of the control systems starts transmitting data when it is detected that the transmission right is not generated or lost from the system, and continues transmitting the data when no collision of data transmitted from the present control system with data transmitted from the rest of the plurality of control systems, or when by mediation for avoiding the collision is detected, it is determined to continue data transmission. According to another aspect, the maximum number of times of retransmission to be permitted is determined according to a type of failure in transmission identified, and the retransmission is performed so long as the number times of retransmission of the data does not exceed the maximum number of times of retransmission to be permitted. According to a still another aspect, the message comprises a first response field for receiving a first acknowledging response output from a control system having received the transmission right, and a second response field for receiving a second acknowledging response output from a control system having received data.

Claims

1. In a data transmission system for a vehicle, including a plurality of control systems installed on said vehicle, and a network bus connecting said plurality of control systems with each other for circulating a transmission right through said plurality of control systems to thereby perform transmission of a message between said plurality of control systems,

the improvement wherein each of said plurality of control systems comprises:

a transmitter-receiver for transmitting data to or receiving data from the rest of said plurality of control systems via said network bus;

collision-detecting means for detecting a collision of data transmitted from said transmitter-receiver with data transmitted from any of the rest of said plurality of control systems;

mediating means for performing mediation on said data transmitted from said transmitter-receiver and having been detected to be collided with said data transmitted from any of the rest of said plurality of control systems to direct said transmitter-receiver to continue data transmission or to stop said data transmission, for the purpose of avoiding said collision of data,

monitor means for monitoring said transmission right;

control means for causing said transmitter-receiver to start transmitting data when said monitor means detects that said transmission right is not generated or lost from said system, and for causing said transmitter-receiver to obtain said transmission right and to continue transmitting said data when said collision-detecting means does not detect a collision of said data with data transmitted from the rest of said plurality of control systems, or when said mediating means directs said transmitter-receiver to continue data transmission;

wherein said mediating means includes means for comparing said data transmitted from said transmitter-receiver with said data received via said network bus from the rest of said plurality of control systems, bit by bit, based on a logic considering one of logical levels of transmission data as dominant, and another of said logical levels of said transmission data as recessive, and for directing said transmitter-receiver to stop said data transmission when said data transmitted from said transmitter-receiver and said data received from said network bus are different from each other; and

transfer means for transferring said transmission right to a subsequent control system in a predetermined manner, when said control means controls said transmitter-receiver to continue said data transmission until said data transmission is completed;

said transfer means transferring said transmission right to said subsequent control unit by increasing an address representative of said each of said plurality of control systems incorporating said transfer means by a predetermined number.