Network system using management frames for supervising control units
First Claim
1. A network system comprising:
- control units disposed for respective controlled devices to be controlled as nodes of a network, the nodes being connected to be capable of communicating data with one another,wherein each control unit has a function of transmitting a management frame for notifying its communication state to any other control units, and the control unit affixes information of a control cause determining its communication state to the management frame,wherein the control unit transmits a start control frame which is the management frame for starting the system to any other control units when it starts,wherein the control unit is started when it receives the start control frame from any other control units during stop of its operation, andwherein the control unit affixes start cause information expressive of a cause of the start of its own to the start control frame as the information of the control cause.
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Accused Products
Abstract
In a network system, each ECU transmits a start control frame when to start, and is started when it receives the start control frame from any other ECU during the stop of its operation. Besides, each ECU transmits a stop control frame cyclically during its operation, and continues its operation in spite of being capable of stopping its operation, while it is receiving the stop control frame from any other ECU. In transmitting each of the frames, each ECU affixes cause information expressive of a start cause or an operation stop incapability cause to the frame. In stopping a network, a supervisory device specifies the start ECU and the start cause thereof from the start control frame and stores them in a nonvolatile memory.
34 Citations
20 Claims
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1. A network system comprising:
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control units disposed for respective controlled devices to be controlled as nodes of a network, the nodes being connected to be capable of communicating data with one another, wherein each control unit has a function of transmitting a management frame for notifying its communication state to any other control units, and the control unit affixes information of a control cause determining its communication state to the management frame, wherein the control unit transmits a start control frame which is the management frame for starting the system to any other control units when it starts, wherein the control unit is started when it receives the start control frame from any other control units during stop of its operation, and wherein the control unit affixes start cause information expressive of a cause of the start of its own to the start control frame as the information of the control cause. - View Dependent Claims (2, 17, 18, 19, 20)
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3. A network system comprising:
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control units disposed for respective controlled devices to be controlled as nodes of a network, the nodes being connected to be capable of communicating data with one another, wherein each control unit has a function of transmitting a management frame for notifying its communication state to any other control units, and the control unit affixes information of a control cause determining its communication state to the management frame, wherein the control unit transmits a stop control frame expressive of incapability to stop the system, as the management frame for stopping the system, at predetermined transmission time intervals during its operation, wherein the control unit suspends transmission of the stop control frame when it falls into a state where it is capable of stopping its operation, and stops its operation when a state where the stop control frame is not transmitted from any other control units continues for, at least, a wait time longer than the transmission time interval after the suspension of the transmission, and wherein the control unit affixes stop incapability cause information expressive of a cause of incapability to stop its operation, to the stop control frame as the information of the control cause. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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15. A network system comprising:
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control units disposed for respective controlled devices to be controlled nodes of a network, the nodes being connected to be capable of communicating data with one another, wherein each control unit has a function of transmitting a management frame for notifying its communication state to any other control units, and the control unit affixes information of a control cause determining its communication state to the management frame, wherein the control unit transmits a start control frame which is the management frame for starting the system to any other control units when it starts, and it is started when it receives the start control frame from any other control unit during stop of its operation, wherein the control unit transmits a stop control frame expressive of incapability to stop the system as the management frame for stopping the system at predetermined transmission time intervals during its operation after the start, wherein the control unit suspends the transmission of the stop control frame when it falls during its operation into a state where it is capable of stopping its operation, and it stops its operation when a state where the stop control frame is not transmitted from any other control unit continues for, at least, a wait time longer than the transmission time interval after the suspension of the transmission, and wherein the control unit affixes start cause information expressive of a cause of the start of its own to the start control frame as the information of the control cause, and also affixes stop incapability cause information expressive of a cause of incapability to stop its operation to the stop control frame as the information of the control cause. - View Dependent Claims (16)
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Specification