JP2604174Y2 - Communication control device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control device which is installed in various devices connected to a local area network, a computer device, etc. and supports a communication operation.
More specifically, the present invention is to improve a method of notifying an energization state among devices.

[0002]

2. Description of the Related Art Local area networks have been adopted in various fields, and computer apparatuses and the like have been connected to this network, and are often operated as one logical system. In such a system, it is indispensable to recognize the operation state of the devices in the system, particularly, the power supply state of each of the other devices in a certain device. Conventionally, the following method has been adopted as a method for mutually recognizing the energized state of devices connected to such a local area network. (1) A communication request is transmitted from a certain device to another device whose power supply state is to be known, and the presence or absence of the response communication is detected. If there is a response communication, the device is in an operating state. State. (2) A device that is energized continuously performs communication indicating its own existence at fixed time intervals, and a device receiving this communication is in a power-off state of another device due to the interruption of communication. Know.

[0003]

The above two methods are known, but these methods have the following problems. That is, the point common to the two methods is that when there is no response communication from the device that inquired about the energization state,
It is not known whether the power was intentionally turned off by the correct procedure by the operator or the power was turned off due to an abnormal state during the operation of the equipment, and it is not possible to know the cause of the power cut of other equipment. However, there is an inconvenience that it may take some time until the energized state of another device can be clearly confirmed. In particular, the fact that the cause of the power interruption of the other device cannot be known is fatal when operating a dynamically connected system. In the method of (1), the time until the power supply state of the other device is known is a waiting time until the response communication is returned from the device inquiring about the power supply state, and in the method of (2), It corresponds to a time equal to the time interval of communication indicating the existence of oneself. However, in the method (2), this problem can be solved by shortening the time interval, but this increases the communication load on the network, which is not preferable.

[0004] The present invention solves such a problem as a problem, and it is possible to quickly find out whether the power supply of a device connected to a local area network is intentional or abnormal. It is an object of the present invention to realize a communication control device capable of performing the following.

[0005]

According to the present invention for achieving the above object, there is provided a communication control device provided in various devices connected to a local area network.
A power-on message transmitting unit that starts up when the power of the device is turned on and creates a message indicating power-on, an exception processing unit that causes a delay from power-off of the device to actual power-off, A power-off message transmitting unit that determines the cause of the power-off when the power switch is turned off and creates a message indicating the cause together with a message indicating the power-off, a message from the power-on message transmitting unit, A communication control unit that broadcasts the message to the local area network when a message is given from the power-off message transmitting unit, and a message holding unit that holds a message broadcasted from another device. Is a communication control device characterized by having the following.

[0006]

The communication control device of the present invention broadcasts a power-on message to another device when the power of the device to be connected is turned on, and turns off the power to another device when the power switch is turned off. A message and a message indicating the cause are broadcast-communicated. Messages from other devices are received by the message holding unit and evaluated.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a conceptual block diagram showing a communication control device according to the present invention. This device is built in various devices such as a computer device installed in a local area network. In this figure, a power-on message transmission section 1 is a block for creating a message indicating power-on when the power to the communication control device is turned on, and a CPU exception generation circuit 2 is turned off (off) by a power switch SW. CP
U (not shown) generates an exception interrupt signal, the exception processing unit 3 receives the exception interrupt signal, generates a delay from the power switch SW disconnection to the actual power disconnection, and the power disconnection message transmission unit 4 A block that receives a signal from the exception processing unit 3 and creates a message indicating power-off and its cause (power-off due to a normal procedure, power-off due to a device abnormality). The communication control unit 4 sends a message from the power-on message transmission unit 1 The message (not shown) and the message from the message transmitting unit 4 when the power is turned off are transmitted to the
A block for broadcast transmission (simultaneous communication to all devices), and a message holding unit 6 is a block for holding a message received by the communication control unit 5 from another device.

Next, the operation of the thus constructed device of the present invention will be described. When the power of the communication control device is turned on, the power-on message transmission unit 1 creates a power-on message indicating that the power is turned on. Then, upon receiving this message, the communication control unit 5 broadcasts this power-on message to other devices connected to the network.

When the power switch SW of the apparatus is turned off (disconnected), the CPU exception generating circuit 2 detects this and sends an exception interrupt signal to the CPU and the exception processing unit 3. The exception processing unit 3 receives the exception interrupt signal, generates a certain delay from the power switch SW disconnection to the actual power disconnection, and transmits the power disconnection signal to the power-off message transmission unit 4. The power-off message transmitting unit 4 determines whether the power-off is a power-off after a normal procedure by an operator or a power-off due to an abnormality occurring inside the apparatus, and indicates the power-off and the cause. Create a message. The cause can be determined by, for example, setting a normal power-off or abnormal power-off flag in the power-off message transmitting unit 4 or obtaining information determined by the CPU. Then, upon receiving this message, the communication control unit 5 broadcasts this message to another device connected to the network.

On the other hand, when the power-on message and the power-off message as described above are broadcasted from another device, the communication control unit 5 receives these messages, and the message holding unit 6 receives these messages. Hold. The CPU reads the message held in the message holding unit 6 and evaluates the message, thereby grasping the energized state or the power-off state of another device and the cause thereof. Further, it is preferable that the message holding unit 6 be in the form of a table corresponding to each device installed in the system so that the energization state of each device can be recognized.

The blocks of the power-on message transmitting unit 1, the power-off message transmitting unit 4, the communication control unit 5, and the message holding unit 6 in the device of the present invention configured as described above are actually software.・ It is good to realize with a program.

[0012]

As described above, according to the communication control device of the present invention, when grasping the energized state of other devices, the message holding unit can be referred to when necessary, so that the communication control device can be executed almost in real time. In addition, the status of other devices can be confirmed without accessing the network. Therefore, the local configuration where the configuration of the connected device is dynamic
Advanced application programs can be built on the area network. Also, the necessary communication may be performed twice when the power is turned on and when the power is turned off.
There is almost no load on the network.

[Brief description of the drawings]

FIG. 1 is a conceptual block diagram illustrating a communication control device of the present invention.

[Explanation of symbols]

 1 Message sending unit at power-on 2 CPU exception generating circuit 3 Exception processing unit 4 Message sending unit at power-off 5 Communication control unit 6 Message holding unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 12/28 H04Q 9/00 301

Claims (1)

(57) [Scope of request for utility model registration] A communication control device provided in various devices connected to a local area network,
A power-on message transmitting unit that starts up when the power of the device is turned on and creates a message indicating power-on, an exception processing unit that causes a delay from power-off of the device to actual power-off, A power-off message transmitting unit that determines the cause of the power-off when the power switch is turned off and creates a message indicating the cause together with a message indicating the power-off, a message from the power-on message transmitting unit, A communication control unit that broadcasts the message to the local area network when a message is given from the power-off message transmitting unit, and a message holding unit that holds a message broadcasted from another device. A communication control device comprising: