Network system having at least one data processor capable of transmitting at least one message more than other data processors

• US 6,816,503 B1
• Filed: 04/20/1999
• Issued: 11/09/2004
• Est. Priority Date: 04/20/1998
• 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: Nagatani, Yuji, Iwamoto, Kazuya, Hashimoto, Hiroshi
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/294,194
• Time in Patent Office: 2,030 Days
• Field of Search: 370/450-457, 370/488, 370/401-404, 370/258, 370/468, 370/224, 370/503, 370/407, 370/336, 370/345, 370/350, 709/216-238, 709/225-228, 709/245, 709/316, 709/246, 340/451, 340/825.52, 340/825.51, 340/531, 455/517, 455/426, 455/552-554
• US Class Current: 370/450
• CPC Class Codes: H04L 12/417 with deterministic access, e.g. token passing
• CPC Class Codes: H04L 2012/40273 the transportation system being a vehicle

Abstract

In a network system which sequentially passes a right to transmit in the form of a token and includes a plurality of data processors, at least one of the plurality of data processors is set so as to be able, during each possession of the token, to send messages in greater number than those transmitted by each of the remaining data processors by at least one. The data processor that is allowed to send many messages consecutively sends messages by inserting, into a token address field included in a message format, its own address during transmission. In the case of a server/client network, a server is set so as to consecutively send a number of messages at a time, while in possession of the token.

Claims

1. A network system which includes a plurality of data processors and sequentially passes a right to transmit, in the form of a token, among said data processors, wherein the token is passed to next data processor when a data processor holding the token has no data to be transmitted or after lapse of a predetermined time, and wherein at least one of said plurality of data processors is set as a high volume transmitting data processor for sending messages at one time in a greater number, by at least one, than the number of messages transmitted at one time by each of the other of said plurality of data processors which are not high volume transmitting data processors, during each token holding time, in such a manner that said high volume transmitting data processor again sets a token address field of a message to be transmitted to an address of said high volume transmitted data processor and thereafter transmits the message so that the token holding time of said high volume transmitting data processor is extended.

2. The network system as claimed in claim 1, wherein said plurality of data processors are configured with one another in a server-client relationship, wherein said high volume transmitting data processor is a server.

3. A network communication system for transmitting and receiving data messages among a plurality of data processing devices, wherein a token, representing a right to transmit, is passed among said plurality of data processing devices, said network communication system comprising:

at least one first data processing device capable of transmitting a first number of said data messages in a fixed transmitting period during which said first data processing device has said right to transmit;

at least one second and high volume transmission data processing device which is capable of transmitting a greater number of said data messages than said first number of said at least one first data processing device in a variable transmitting period greater than said fixed period during which said at least one high volume transmission data processing device possesses said right to transmit; and

a network bus over which said data messages are transmitted, wherein said network bus is connected to said at least one first data processing device and said at least one high volume transmission data processing device.

4. A network communication system for transmitting and receiving data messages among a plurality of data processing devices, wherein a token, representing a right to transmit, is passed among said plurality of data processing devices, said network communication system comprising:

at least one first data processing device;

at least one second and high volume transmission data processing device which is capable of transmitting a greater number of said data messages than said at least one first data processing device in a transmitting period during which said at least one high volume transmission data processing device possesses said right to transmit; and

a network bus over which said data messages are transmitted, wherein said network bus is connected to said at least one first data processing device and said at least one high volume transmission data processing device, wherein said at least one high volume transmission data processing device comprises;

a communication controller comprising;

a data reception system for sampling said data messages transmitted over said network bus;

a transmission section wherein outgoing data messages prepared by said at least one high volume transmission data processing device are stored and output to said network bus;

a token detection unit which monitors said data messages received in said data reception system, wherein said token detection unit detects said token within a token address field of a data message format, and wherein said token detection unit determines whether or not said token is addressed to said at least one high volume transmission data processing device,

a transmission control section which, upon receiving a token detect signal from said token detection unit, causes said transmission section to output one of said outgoing data messages after setting a next token address in said token address field of said one of said outgoing data messages; and

a counter which determines said transmitting period during which said at least one high volume transmission data processing device can transmit said greater number of said data messages.

5. A network communication system as claimed in claim 4, wherein said counter counts a quantity of said outgoing data messages transmitted by said at least one high volume transmission data processing device during said transmitting period, wherein said at least one high volume transmission data processing device has a high volume transmission data processing device address, wherein said at least first data processing device has a first data processing device address, wherein said next token address is said high volume transmission data processing device address during said transmitting period, and wherein said next token address is said first data processing device address after said transmitting period expires.

6. A network communication system as claimed in claim 5, wherein said transmitting period of said at least one high volume transmission data processing device expires either when said counter reaches a predetermined limit, or when said at least one high volume transmission data processing device has no said outgoing messages to transmit.

7. A network communication system as claimed in claim 4 wherein said counter counts clock pulses used to synchronize said at least one high volume transmission data processing device, wherein said at least one high volume transmission data processing device has a high volume transmission data processing device address, wherein said at least one first data processing device has a first data processing device address, wherein said next token address is said high volume transmission data processing device address during said transmitting period, and wherein said next token address is said first data processing device address after said transmitting period expires.

8. A network communication system as claimed in claim 7, wherein said transmitting period of said at least one high volume transmission data processing device expires either when said counter reaches a predetermined limit, or when said at least one high volume transmission data processing device has no said outgoing messages to transmit.

9. A method for controlling transmission of data messages among a plurality of data processing of a network system, wherein said plurality of data processing devices comprises at least one second and high volume transmission data processing device which is capable of transmitting a greater number of said data messages than first data processing devices in a transmitting period during which said at least one high volume transmission data processing device possesses a right to transmit, wherein said method comprises:

processing, in said at least one high volume transmission data processing device, outgoing messages to be transmitted over said network bus;

monitoring, in said at least one high volume transmission data processing device, said data messages transmitted over a network bus;

outputting one of said outgoing messages from said at least one high volume transmission data processing device after setting a next token address in a token address field of said one outgoing message, when said at least one high volume transmission data processing device detects an address corresponding to said at least one high volume transmission data processing device in said monitoring step; and

controlling said transmitting period to allow said at least one high volume transmission data processing device to sequentially output said greater number of said data messages during said transmitting period, by setting said next token address to be an address of said at least one high volume transmission data processing device.

10. A method for controlling transmission of data messages as claimed in claim 9, wherein said controlling step comprises:

receiving a token indicating that said at least one high volume transmission data processing device is granted said right to transmit;

determining if there are any of said outgoing messages ready to transmit to said at least one high volume transmission data processing device, wherein a counter is incremented by one if it is determined that there is at least one of said outgoing messages ready to transmit;

setting said next token address to said same address of said at least one high volume transmission data processing device if;

1) said determining step determines that there is said at least one of said outgoing messages ready to transmit; and

2) said counter has not counted up to a predetermined counter value; and

resetting said counter to zero and setting said next token address to a next node address of a next data processing device to which said token is to be passed if;

1) said determining step determines that there is no said at least one of said outgoing messages ready to transmit;

or

2) said determining step determines that there is said at least one of said outgoing messages ready to transmit, and said counter has counted up to said predetermined counter value.

11. A network communication system for transmitting and receiving data messages among a plurality of data processing devices, wherein a token, representing a right to transmit, is passed among said plurality of data processing devices, said network communication system comprising:

at least one high volume transmission data processing device; and

at least one regular data processing device;

wherein said at least one high volume transmission data processing device has the ability to address said token to itself.

12. A network communication system as claimed in claim 11, wherein said at least one high volume transmission data processing device further comprises:

a counter, which enables said at least one high volume transmission data processing device to retain said token by addressing said token to itself if said at least one high volume transmission data processing device has said data messages to transmit and if said counter has not reached an end of a count cycle.

13. A network communication system as claimed in claim 12, wherein said counter counts a quantity of said outgoing data messages transmitted by said at least one high volume transmission data processing device to increment said counter during said count cycle, wherein said at least one high volume transmission data processing device passes said token to said at least one high volume transmission data processing device during said count cycle, and wherein said at least one high volume transmission data processing device passes said token to another of said plurality of data processing devices after said counter reaches the end of said count cycle.

14. A network communication system as claimed in claim 12, wherein said counter counts clock pulses to increment said counter during said count cycle, wherein said at least one high volume transmission data processing device passes said token to said at least one high volume transmission data processing device during said count cycle, and wherein said at least one high volume transmission data processing device passes said token to another of said plurality of data processing devices after said counter reaches the end of said count cycle.