JPH066869A - Monitor control communication system - Google Patents

Abstract

PURPOSE:To provide a monitor control communication system in which data indicating the state of a controller to be monitored can be obtained without waiting the state change of the controller to be monitored, even when a monitor controller loses the data indicating the state of the controller to be monitored due to any fault such as a temporary power source interruption, etc. CONSTITUTION:A monitor controller 1 is equipped with a control part 13 which outputs a control output, control signal transmitting part 11 which transmits a polling signal or a forced transmission instruction signal by the control from the control part 13, and response signal receiving part 12 which receives a response signal. Then, a controller 2 to be monitored is equipped with a control signal receiving part 21 which outputs the detection signal of a polling and the forced transmission instruction signal, state change detecting part 23 which outputs a state change detection signal, logical product part 24 which outputs the logical product of the detection signal and the state change detection signal, and response signal transmitting part 22 which transmits the data indicating the state of its own device at the time of inputting the forced signal or the logical product output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a supervisory control communication system, and in particular, in exchanging data between a supervisory control device and a monitored control device, the supervisory control device can take the lead in collecting data to be monitored. The present invention relates to an improved supervisory control communication system.

[0002]

2. Description of the Related Art Conventionally, this type of supervisory control communication system is shown in FIG.
Are shown in the block diagram and the time chart of FIG. As shown in FIG. 3, the monitoring controller 3 includes a control signal transmitter 31.
And a response signal receiver 32, and the monitored and controlled device 4 is
The control signal receiver 41, the response signal transmitter 42, and the state change detector 43 are provided.

The operation of each part of the conventional example will be described with reference to the time chart of FIG. The monitoring control device 3 polls signals P (1) to P (n + 1) for requesting monitoring data from the control signal transmitting unit 31 to the monitored control device 4 at regular intervals.
To send. The monitored control device 4 includes a control signal receiving unit 41.
The polling signals P (1) to P (n + 1) signals are received at. When there are a plurality of monitored control devices, the control signal receiving unit 41 sends the polling signals P (1) to P (P) to the response signal transmitting unit 42 when receiving a signal for the own device.
The detection signal d is output corresponding to (n). On the other hand, the state change detection unit 43, when there is a change in the state of its own device,
The state change detection signal e is output to the response signal transmission unit 42. The response signal transmitter 42 sends the response signal g to the response signal receiver 32 on the other side. There are two types of response signals g. First, when both the state change detection signal e and the detection signal d are received, the data D (n) representing the state of the own device is transmitted to the monitoring control device 3. . Secondly, when only the detection signal d is received, a flag F indicating that there is no change in the state of the own device is transmitted to the monitoring control device 3. In the monitoring control device 3, the response signal receiving unit 32 receives the data D (n) indicating the state of the monitored control device 4 or the flag F.

[0004]

In the above-described conventional supervisory control communication system, when the monitored control device receives a signal from the supervisory control device, it changes to the state of its own device as indicated by E1 in FIG. When the supervisory control device loses the data representing the state of the monitored control device due to some failure such as temporary power failure, the data of the monitored control device is sent only when there is There is a drawback that the status of the monitored and controlled device cannot be obtained until the status changes.

[0005]

According to the supervisory control communication system of the present invention, a supervisory control device sends a control output signal for requesting information of a monitored control device to be monitored as necessary. And a control signal transmission unit for transmitting a polling signal or a forced transmission instruction signal for instructing the monitored control device to transmit data indicating the state of the monitored control device according to a control output signal from the control unit. And a response signal receiving unit that receives a response signal from the monitored control device, wherein the monitored control device outputs a forced signal when receiving a forced transmission instruction signal from the monitoring control device, and performs polling. A control signal receiving unit that outputs a detection signal when receiving a signal, a state change detection unit that outputs a state change detection signal when a state change of the own device is detected, a polling detection signal and the above A logical product section that outputs a logical product signal with a state change detection signal, and the forced signal and the logical product signal are input, and in the case of the forced signal or the logical product signal, data indicating the state of the device itself is transmitted. And a response signal transmitting section for

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a time chart explaining this embodiment. That is, in this embodiment, the control unit 13 is added to the monitoring control device 1 and the logical product unit 24 is added to the monitored control device 2.

Next, the operation of this embodiment will be described. First, the function of each signal will be described. P1 to P of the polling signal b
(N + 1) is a polling signal having a constant period, which is transmitted from the monitoring control device 1 to the monitored control device 2. R (n) of the forced transmission instruction signal c is the n-th forced transmission instruction signal transmitted from the monitoring controller 1 to the monitored controller 2. The flag F of the response signal g is a flag indicating that there is no state change transmitted from the monitored control device 2 to the monitoring control device 1, and is a response signal to the polling signal P (n). The data D (n) is data indicating the state of the monitored control device 2 transmitted from the monitored control device 2 to the monitoring control device 1, and is the polling signal P (n) or the forced transmission instruction signal R (n). Is a response signal to. E1 is a state change of the monitored and controlled device 2.

Next, the operation of each section will be described. When data indicating the state of the monitored control device 2 is needed, such as when the monitoring control device 1 loses data indicating the state of the monitored control device 2 due to some failure, the control unit 13 causes the control signal transmission unit 11 to In response, the control signal a is output. The control signal transmission unit 11 transmits the forced transmission instruction signal R (n) to the monitored control device 2 when receiving the control signal a, and the conventional example when it does not receive the transmission control signal a. Similarly, the polling signal P (n) is transmitted. The monitored control device 2 is
The control signal receiving unit 21 receives a signal for the device itself from the monitoring control device 1, and outputs the detection signal d to the AND unit 24. When the received signal is the forced transmission instruction signal R (n), the forced signal c is directly output to the response signal transmission unit 22. The state change detection unit 23 outputs a state change detection signal e to the AND unit 24 when there is a change in the state of the device itself. The logical product unit 24 takes the logical product of the detection signal d output from the control signal receiving unit 21 and the state change detection signal e output from the state change detecting unit 23, and logically calculates the logical product for the response signal transmitting unit 22. The product signal f is output. When the response signal transmission unit 22 receives the forced transmission instruction signal c, the response signal transmission unit 22 transmits the data D (n) indicating the state of the own device to the monitoring control device 1 regardless of whether the state of the own device changes. However, when only the logical product output f is received, the flag F indicating that there is no state change is transmitted to the monitoring control device 1. The monitoring control device 1 repeats the operation of receiving the data D (n) indicating the state of the monitored control device 2 or the flag F at the response signal receiving unit 12. As described above, the monitoring control device 1 sends the forced transmission instruction signal R to the monitored control device 2.
By transmitting (n), it is possible to obtain data representing the state of the monitored control device 2 without waiting for the state change of the monitored control device 2.

It should be noted that the monitored control device can be realized by a plurality of units, and although the monitoring control device and each part of the monitored control device are configured by hardware, they can also be realized by software.

[0010]

As described above, according to the present invention, by having a control unit for transmitting a forced transmission instruction signal to the monitored control device, the monitoring control device is monitored by some trouble such as temporary power interruption. Even if the data representing the state of the control device is lost, the data representing the state of the monitored control device can be obtained without waiting for the state change of the monitored control device.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a time chart of each signal of this embodiment.

FIG. 3 is a block diagram of a conventional supervisory control communication system.

FIG. 4 is a time chart of a conventional example.

[Explanation of symbols]

 1, 3 Monitor and control device 2, 4 Monitored and controlled device 11 Control signal transmitting unit 12 Response signal receiving unit 13 Control unit 21 Control signal receiving unit 22 Response signal transmitting unit 23 State change detecting unit 24 Logical AND unit

Claims (1)

[Claims] 1. A monitoring control device sends a control output signal for requesting information of a monitored control device to be monitored, as necessary, and the controlled output signal from the control part. Polling signal to the supervisory controller,
Or a control signal transmitting unit for transmitting a forced transmission instruction signal for instructing to transmit data representing the state of the monitored control device, and a response signal receiving unit for receiving a response signal from the monitored control device, The monitored control device outputs a forced signal in the case of receiving a forced transmission instruction signal from the monitoring control device, and outputs a detection signal in the case of receiving a polling signal, and a state change of its own device. A state change detection unit that outputs a state change detection signal when detected,
A logical product unit that outputs a logical product signal of a polling detection signal and the state change detection signal, the forced signal and the logical product signal are input, and in the case of the forced signal or the logical product signal, its own device A supervisory control communication system, comprising: a response signal transmitter that transmits data representing a state.