JPH0234519B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a monitoring control device using a cyclic transmission method having a plurality of monitoring items that change state within a certain period of time among the monitoring items constituting a monitoring input signal. The present invention relates to a supervisory control device that enables state changes of specific items to be transmitted quickly from a monitored station to a monitoring station using supervisory signals in the same cycle.

Conventionally, as shown in FIG. 1, in a monitoring and control device for a monitored station that performs cyclic transmission, a monitoring input signal 1 consisting of a plurality of monitoring items is input to a scanning circuit 3 and sequentially scanned, and then the signal is output from an encoding circuit 4. It is input to the encoding circuit 4 at the timing of the end of the synchronization code of the sent monitoring signal 2. The input signal is generated by the encoding circuit 4 into a monitoring signal 2 consisting of a synchronization code, data, and check code in one cycle as shown in signal 2 in FIG. 3, and then sent to the transmission path. Ru. Therefore, if the state of the monitoring input signal changes while the data of the monitoring signal 2 is being sent to the transmission path, the changed contents are encoded at a timing delayed by a maximum of one cycle (T time) and the next cycle It becomes the monitoring signal 2 and is sent out to the transmission path.

In other words, if the state of the monitoring input signal 1 changes before and after the timing when the scanned signal is input to the encoding circuit 4, the information will be transmitted to the monitoring station between the item whose state changed before the timing and the item whose state changed after the timing. This results in a difference in time by a time T corresponding to one cycle.

For this reason, the transmission time for one cycle is long, and a system in which a judgment process is automatically performed on the monitoring station side based on the contents of the monitoring signal 2 has the disadvantage of causing malfunction.

When the present invention detects a change in the state of the monitoring input signal, it stops the monitoring signal being sent to the transmission line, and after sending out an interrupt code meaning abandoning the previous cycle's monitoring signal, the monitoring input signal is newly scanned. By sending a monitoring signal to the transmission line, the above disadvantages can be eliminated, and the contents of a specific item whose state changes within a certain period of time can be transmitted as a monitoring signal in the same cycle and quickly transmitted to the monitoring station. The purpose of this invention is to provide a device that provides

That is, according to the present invention, in a supervisory control device that repeatedly scans an input supervisory input signal, encodes it into a supervisory signal, and then cyclically transmits the encoded supervisory signal at a period T time, means for detecting a change in the input supervisory input signal is provided. When a change in the monitoring input signal is detected, an interrupt code whose length is less than or equal to the length of the monitoring signal already sent to the transmission path when this change is detected is sent to the transmission path from the T time. a means of sending,
The present invention is characterized by comprising means for discarding the supervisory signal sent to the transmission line by sending the interrupt code, and for scanning the supervisory input signal anew again and starting transmitting the generated supervisory signal.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a functional block diagram of an embodiment of the present invention, in which 1 is a monitoring input signal, 5 is a scanning circuit, 6 is an encoding circuit, 7 is a change detection signal, 8 is a change processing circuit, and 9 is an interrupt code. , 10 is an interlock signal, 11 and 12 are monitoring signals, and 14 is a switching switch. FIG. 3 shows a procedure for transmitting a supervisory signal according to the embodiment of FIG. This embodiment will be explained with reference to FIG. A monitoring input signal 1 consisting of a plurality of monitoring items enters the scanning circuit 5 and is selectively scanned one item at a time.
It is compared with the contents when scanned a cycle ago.
As a result of the comparison, if no state change is detected in the monitoring input signal 1, the monitoring signal 11 is cyclically sent out to the transmission line in the same state as in the prior art. On the other hand, if a state change is detected in the monitoring input signal 1 as a result of the comparison, the change processing circuit 8
A change detection signal 7 is sent out from the change processing circuit 8, an interlock signal 10 is sent to the encoding circuit 6, the encoding circuit 6 is cleared, and the sending of the monitoring signal 12 is stopped. At the same time, the change processing circuit 8 sends out the interrupt code 9, and the switch SW 14 switches the monitoring signal 12 to the interrupt code 9, and sends it to the transmission path. In other words, as shown in FIG. 3, the monitoring signal 11 sent to the transmission line is the #n-1th cycle that was sent to the transmission line at the time when the monitoring input signal 1 changed and the change detection signal 7 was generated. The signal 12 is abandoned by the interrupt code 9, and then the newly scanned monitoring input signal 1 is converted into the #nth and subsequent monitoring signals 11 and 12 and sent to the transmission path.

The interrupt code is a monitoring signal 1 of the same cycle as the monitoring item that caused the occurrence of the interrupt code.
#n-1 cycle at the monitoring station due to the delay time for sending it to the monitoring station as 1 and 12, and the relationship between the #n-1 cycle monitoring signal 11 and the #n-th cycle monitoring signal 11 sent subsequently. This is to prevent malfunctions due to inability to determine whether the eye monitoring signal 11 has been abandoned.

This interrupt code has the effect of simultaneously transmitting the contents of a change in the state of a specific item, and of transmitting the changed contents more quickly.

As explained above, the present invention provides a supervisory signal transmission method in which, when a change occurs in the state of the supervisory input, the supervisory signal that has already been sent to the transmission path is abandoned by sending an interrupt code to the transmission path. By configuring the system so that the monitoring signal of the new cycle is sent to the transmission line after the interrupt signal is sent, changes in the status of specific items that occur within a certain period of time can be simultaneously transmitted from the monitored station to the monitoring station. There are advantages.

Further, there is an effect that the contents of the changed monitoring input signal can be transmitted more quickly and without errors.

[Brief explanation of drawings]

Figure 1 is a functional block diagram of the conventional technology;
The figure shows a functional block diagram of one embodiment of the present invention, and FIG. 3 shows a procedure for transmitting a supervisory signal in the embodiment of FIG. In the figure, 1...Monitoring input signal, 2...Monitoring signal, 3...Scanning circuit, 4...Encoding circuit, 5
... Scanning circuit, 6 ... Encoding circuit, 7 ... Change detection signal, 8 ... Change processing circuit, 9 ... Interruption code, 10 ... Interlock signal, 11, 12 ...
Monitoring signal, 14...Switching SW, 15... Code configuration of one cycle of monitoring signal.

Claims (1)

[Claims] 1. In a supervisory control device that repeatedly scans an input supervisory input signal, encodes it into a supervisory signal, and then transmits it cyclically at a period T time, means for detecting a change in the input supervisory input signal, and means for detecting a change in the supervisory input signal. If a change is detected, from said T time,
When this change is detected, the length of the supervisory signal already sent to the transmission route is subtracted from the length of the interrupt code, and the length of the supervisory signal sent to the transmission route is What is claimed is: 1. A supervisory control device comprising means for scanning a new supervisory input signal and starting sending out the generated supervisory signal.