Multiplex transmission system

• US 5,343,475 A
• Filed: 03/31/1992
• Issued: 08/30/1994
• Est. Priority Date: 04/02/1991
• Status: Expired due to Fees

• Current Assignee: Furukawa Electric Company Limited, Mazda Motor Corporation
• Original Assignee: Furukawa Electric Company Limited, Mazda Motor Corporation
• Inventors: Matsuda, Yutaka, Sakamoto, Hiroaki, Nobutoki, Yoshikazu, Moriue, Hiroo, Hirano, Seiji
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): Patel, Ajit
• Application Number:
  US07/860,896
• Time in Patent Office: 882 Days
• Field of Search: 370/85.1, 370/85.13, 370/94.1, 370/94.3, 370/110.1, 370/9, 307/10.1, 307/39, 340/825.5, 340/825.51, 340/825.57, 340/825.04, 340/825.05, 371/32, 371/33, 375/22
• US Class Current: 370/432
• 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 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04L 12/4135 using bit-wise arbitration

Abstract

A multiplex transmission system of this invention includes a plurality of multiplex nodes interconnected by a common multiplex transmission line. A plurality of groups of different combinations of the multiplex nodes are predetermined, and a frame of data is transmitted among the multiplex nodes through the multiplex transmission line. The data frame includes a group specifying area specifying a group of nodes from which an acknowledge signal is to be returned. When a data frame transmitted from a sending node is received, each multiplex node determines whether or not it belongs to the group specified by bits in the group specifying area of the transmitted frame. When the data frame is properly received, only those multiplex nodes which belong to the specified group return the acknowledge signals to an acknowledge signal area in the data frame in accordance with the bits in the group specifying area, whereby the transmission efficiency is improved.

Claims

1. A multiplex transmission system comprising:

a plurality of multiplex nodes;

a common multiplex transmission line means for interconnecting said plurality of multiplex nodes and for transmitting a frame of data among the multiplex nodes through the common multiplex transmission line;

said multiplex nodes including means for sending out an acknowledge signal, when a data transmission of a frame of data is properly carried out, for indicating a proper completion of the data transmission, and for returning said acknowledge signal to an acknowledge signal area provided in the frame of data corresponding to the respective multiplex nodes;

wherein the frame of data further includes a group identifier specifying more than one group of predetermined combinations of multiplex nodes from which an acknowledge signal is to be returned, and an acknowledge signal area having locations thereof assigned to said multiplex nodes from which the acknowledge signal is to be returned, the acknowledge signal area having a length which is variable depending on the group identifier;

the multiplex nodes, which belong to a specified group specified by the group identifier, each including means for returning an acknowledge signal in accordance with the group identifier in the transmitted frame of data; and

wherein the multiplex nodes which do not belong to the specified group do not return the acknowledge signal.

2. A multiplex transmission system according to claim 1, wherein the identifier specifies on a bit-wise basis a group of multiplex nodes from which the acknowledge signal is to be returned.

3. A multiplex transmission system according to claim 1, wherein the identifier specifies by a binary code a group of multiplex nodes from which the acknowledge signal is to be returned.

4. A multiplex transmission system according to claim 1, wherein each of the multiplex nodes includes:

memory means for storing data indicating all multiplex nodes from which the acknowledge signal is to be returned in a table corresponding to the respective groups of predetermined combinations of the multiplex nodes,

means for specifying a group of multiplex nodes from which the acknowledge signal is to be returned in accordance with the data stored in the table when a frame of data is transmitted, and

means for returning the acknowledge signal in accordance with the data stored in the table when a frame of data is received.

5. A multiplex transmission system according to claim 1, wherein each of the multiplex nodes belong to one group, or two or more groups.

6. A multiplex transmission system according to claim 1, wherein each of the groups comprise several or all of the multiplex nodes interconnected by the multiplex transmission bus.

7. A multiplex transmission system according to claim 1, wherein said multiplex transmission system is included in an automobile control system for controlling functions in the automobile, and wherein said multiplex nodes include means for controlling respective functions in the automobile.

8. A multiplex transmission system comprising:

a plurality of multiplex nodes;

a common multiplex transmission line means for interconnecting said plurality of multiplex nodes and for transmitting a frame of data among the multiplex nodes through the multiplex common transmission line;

wherein when a data transmission of a frame of data is properly carried out, said multiplex nodes send out an acknowledge signal indicating a proper completion of the data transmission, which acknowledge signal is returned to an acknowledge signal area provided in the frame of data corresponding to the respective multiplex nodes;

the frame of data further including an identifier which specifies more than one group of predetermined combinations of multiplex nodes from which the acknowledge signal is to be returned, and an acknowledge signal area having locations thereof assigned to said multiplex nodes from which the acknowledge signal is to be returned, the acknowledge signal area having a length which is variable depending on the group identifier; and

wherein the multiplex nodes which belong to a specified group return the acknowledge signal in accordance with the identifier in the transmitted frame of data; and

each of said multiplex nodes including;

memory means for storing data indicating all multiplex nodes from which the acknowledge signal is returned in a table corresponding to the respective groups of predetermined combinations of the multiplex nodes,

means for specifying a group of multiplex nodes from which the acknowledge signal is to be returned in accordance with the data stored in the table when a frame of data is transmitted, and

means for returning the acknowledge signal in accordance with the data stored in the table when a frame of data is received.

9. A multiplex transmission system according to claim 8, wherein the identifier specifies on a bit-wise basis a group of multiplex nodes from which the acknowledge signal is to be returned.

10. A multiplex transmission system according to claim 8, wherein the identifier specifies by a binary code a group of multiplex nodes from which the acknowledge signal is to be returned.

11. A multiplex transmission system according to claim 8, wherein each of the multiplex nodes belong to one group, or two or more groups.

12. A multiplex transmission system according to claim 8, wherein each of the groups comprise several or all of the multiplex nodes interconnected by the multiplex transmission bus.

13. A multiplex transmission system according to claim 8, wherein said multiplex transmission system is included in an automobile control system for controlling functions in the automobile, and wherein said multiplex nodes include means for controlling respective functions in the automobile.

14. A multiplex transmission system comprising:

a plurality of multiplex nodes;

a common multiplex transmission line means for interconnecting said plurality of multiplex nodes and for transmitting a frame of data among the multiplex nodes through the common multiplex transmission line;

said multiplex nodes including means for sending out an acknowledge signal, when a data transmission of a frame of data is properly carried out, for indicating a proper completion of the data transmission, said acknowledge signal being returned to an acknowledge signal area provided in the frame of data corresponding to the respective multiplex nodes,

and wherein;

the frame of data further includes an identifier specifying more than one group of predetermined combinations of multiplex nodes from which an acknowledge signal is to be returned, and an acknowledge signal area having locations thereof assigned to said multiplex nodes from which the acknowledge signal is to be returned, the acknowledge signal area having a length which is variable depending on the group identifier;

the multiplex nodes, which belong to a specified group specified by the identifier, each including means for returning an acknowledge signal in accordance with the identifier in the transmitted frame of data;

the multiplex nodes which do not belong to the specified group do not return the acknowledge signal; and

wherein each of the multiplex nodes includes;

memory means for storing data indicating all multiplex nodes from which the acknowledge signal is returned in a table corresponding to the respective groups of predetermined combinations of the multiplex nodes,

means for specifying a group of multiplex nodes from which the acknowledge signal is to be returned in accordance with the data stored in the table when a frame of data is transmitted, and

means for returning the acknowledge signal in accordance with the data stored in the table when a frame of data is received.

15. A multiplex transmission system included in an automobile control system for controlling functions in the automobile, comprising:

a plurality of multiplex nodes, said multiplex nodes including means for controlling respective functions in the automobile;

a common multiplex transmission line means for interconnecting said plurality of multiplex nodes and for transmitting a frame of data among the multiplex nodes through a common multiplex transmission line;

said multiplex nodes including means for sending out an acknowledge signal, when a data transmission of a frame of data is properly carried out, for indicating a proper completion of the data transmission, said acknowledge signal being returned to an acknowledge signal area provided in the frame of data corresponding to the respective multiplex nodes;

wherein the frame of data further includes an identifier specifying more than one group of predetermined combinations of multiplex nodes from which an acknowledge signal is to be returned, and an acknowledge signal area having locations thereof assigned to said multiplex nodes from which the acknowledge signal is to be returned, the acknowledge signal area having a length which is variable depending on the group identifier;

the multiplex nodes, which belong to a specified group specified by the identifier, each including means for returning an acknowledge signal in accordance with the identifier in the transmitted frame of data; and

wherein the multiplex nodes which do not belong to the specified group do not return the acknowledge signal.