JPH10243001A - Communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the communication system that recognizes a slave station communication equipment having been connected at first to a transmission line is disconnected from the transmission line due to any reason during interruption of power without a manual registration operation of slave station communication equipments on the transmission line by a master station communication equipment. SOLUTION: In the communication system where communication is executed based on a station number between a master station communication equipment 3 and a slave station communication equipment 4 connected to a transmission line 1, in the case that the slave station communication equipment 4 receives no communication data from a master station communication equipment 3 with respect to a station number of its own station even after the lapse of a prescribed time t1 after application of power, the slave station communication equipment 4 sends station number communication data including the slave number of its own station to the master station communication equipment 3 and executes usual communication processing when the master station communication equipment 3 gives a reply with respect to the station number communication data. The slave station communication equipment 4 sends the station number communication data repetitively for each prescribed time t2 till a reply comes from the master station communication equipment 3 when no reply comes from the master station communication equipment 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention connects a single master station communication device and one or more slave station communication devices on a transmission line, and furthermore, all the slave station communication devices have a unique station number. The present invention relates to a communication system in which a master station communication device and a slave station communication device execute data communication in accordance with the assigned station number.

[0002]

2. Description of the Related Art FIG. 9 shows a schematic configuration of a conventional communication system. In this communication system, a single master station communication device 3 and a single or a plurality of slave station communication devices 4-1, 4-2,...
4-n are connected, and communication is performed between the master station communication device 3 and the slave station communication devices 4-1, 4-2,..., 4-n based on the station number. is there. In FIG. 9, 1 is a transmission line, 2 is a terminal connected to both ends of the transmission line 1, 3 is a master station communication device, 4-1, 4-2,... A storage unit built in the master station communication device 3 for storing data necessary for data communication; 6, a setting unit for setting data in the storage unit 5 of the master station communication device 3 or changing the data content of the storage unit 5; , 7-n denote station number holding units which are built in the slave station communication devices 4-1, 4-2,..., 4-n and hold respective unique station numbers.

Normally, in order to start communication in the 1: n communication system, each of the slave stations communication devices 4-1, 4-2,... Information that the communication device is connected (station number, etc.) must be manually registered in the setting unit 6 of the master station communication device 3. On the other hand, Japanese Patent Application Laid-Open No. 63-124644 proposes a system in which registration of station numbers is automated.

[0004]

In the conventional method of manually registering a station number or the like, a registration operation is required,
When the slave station communication device is disconnected from the transmission line for any reason (due to disconnection, short circuit, etc.), the master station communication device confirms that there is no reply from the slave station communication device of the registered station number, and checks that slave station communication device. It can be recognized that the communication device was initially connected, but has been disconnected for some reason. On the other hand,
According to the method described in JP-A-3-124644, the slave station communication device can be automatically recognized, but only the slave station connected when the power is turned on is recognized. In the case of disconnection, the master station communication device determines that the detached slave station communication device was not connected from the beginning, so it cannot recognize that the slave station communication device that was initially connected has been disconnected. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to eliminate the need for a master station communication device to manually register a slave station communication device on a transmission path. However, it is an object of the present invention to provide a communication system which can recognize that a slave station communication device which has been initially connected is disconnected from a transmission line for some reason while the power is shut off.

[0006]

According to the present invention, in order to solve the above-mentioned problems, as shown in FIG.
A single master station communication device 3 and one or more slave station communication devices 4 each having a unique station number are connected thereto, and a station number is set between the master station communication device 3 and the slave station communication device 4. The master station communication device 3 transmits the communication data requesting a reply by designating the station number of the slave station communication device 4 on the transmission line 1.
By transmitting the reply data including the station number and the station type from the slave station communication device 4 connected to the transmission line 1, thereby transmitting the slave station communication device 4 connected to the transmission line 1. The station number and the station type are recognized and stored. The combination of the station number and the station type of the slave station communication device 4 on the transmission line 1 recognized by the master station communication device 3 and the previously stored transmission line 1
Means for determining whether there has been a change in the configuration of the slave station communication device 4 connected to the transmission line 1 by comparing the combination of the station number and the station type of the slave station communication device 4 above, If there is a change, means for displaying the changed station number and station type and means for selecting whether or not to change the previously stored content are provided. If the communication data from the master station communication device 3 is not received for the own station number even after
Station number communication data including the station number of the own station is transmitted from the slave station communication device 4 to the master station communication device 3, and if there is a reply from the master station communication device 3, the normal communication is performed. The processing is executed, and if there is no reply from the master station communication device, the station number communication data is repeatedly transmitted at predetermined time t2 until there is a reply.

[0007]

FIG. 1 shows a communication system according to a first embodiment of the present invention, in which a transmission line 1, a terminal 2 connected to both ends of the transmission line 1, and a transmission line 1 connected thereto. A single master station communication device 3 and n slave station communication devices 4-i (i = 1, 2).
2, 3,..., N). Master station communication device 3
Is a storage unit 5 for storing the station number and station type of the slave station communication device 4-i connected on the transmission line 1, and a storage unit for retaining the contents even when the power is shut off. 8, a display unit 9 capable of displaying the increase / decrease of the station number and the change of the station type, a switch 10 for changing the contents of the storage unit 8 when the contents of the storage unit 5 and the storage unit 8 are different, and a storage unit 8 The switch 11 which does not change the contents of. Slave station communication device 4-i
Are the station number holding units 7-i (i = 1, 2, 3,...,
n).

The operation of this embodiment will be described below with reference to FIGS. FIG. 2 is a flowchart illustrating the operation of the master station communication device 3 in the present embodiment, and FIG. 3 is a flowchart illustrating the operation of the slave station communication device 4-i in the present embodiment. First, it is assumed that a maximum of m slave station communication devices 4 can be connected on the transmission line 1. Before starting the data communication, the master station communication device 3 requests the slave station communication device 4 of the station number j (j = 1, 2, 3,..., M) to request the slave station communication device 4 for the station number and the station type. Hereinafter, “connection confirmation communication data” is transmitted.

[0009] Upon receiving the connection confirmation communication data, the slave station communication device 4 on the transmission line 1 having the station number j sends the master station communication device 3 communication data including the station number and the station type (hereinafter referred to as "connected slave station"). Information communication data ”) and then proceeds to normal communication processing. Since the slave station communication device 4 other than the station number j has a different station number and own station number in the received connection confirmation communication data,
It does not reply to this connection confirmation communication data, but waits for the connection confirmation communication data for its own station number.

[0010] After transmitting the connection confirmation communication data, the master station communication device 3 receives the connected slave station information communication data from the slave station communication device 4 of the station number j within a certain period of time. It is determined that the device 4 is connected to the transmission line 1 and communicable, and the station number and the station type are registered in the storage unit 5 built in the master station communication device 3 as shown in FIG.
If there is no reply from the slave station communication device 4 of the station number j within the fixed time, the station number and the station type are not registered.

The master station communication device 3 performs the following processing j = 1.
This is executed for the slave station communication devices of all the station numbers of .about.m. In the master station communication device 3, displaying the slave station connection information on the transmission path 1 at the time of the previous change and the recognized slave station connection information on the transmission path 1 by comparison is, for example, a 1: n communication system. If the transmission line is disconnected without being noticed while the power is shut down during maintenance work, etc., or if only the slave station communication device 4 breaks down while the power is shut down, the power is shut down. There is an effect that the master station can recognize at the time of power-on that the slave station connection information on the transmission line has changed from the state after construction. In particular, when the slave station communication device 4 is located very far from the master station communication device 3 or when the slave station communication device 4 is not easily reachable, the slave station communication device 4 displays the display unit. In the case where it is difficult to judge whether or not it is operating normally in appearance and the number of slave station communication devices 4 is very large, the master station communication device 3 can recognize slave station connection information on the transmission path. , Very effective. In this case, the master station communication device 3
Automatically recognizes the slave station communication device 4 on the transmission line 1, so that manual registration is not required.

When the processing of (1) to (3) is performed on the slave station communication apparatuses of all the station numbers j = 1 to m, the master station communication apparatus 3 compares the contents of the storage unit 5 and the contents of the storage unit 8. The storage unit 8 stores the slave station connection information on the transmission line 1 at the time of the previous change, and if the contents of the storage unit 5 and the storage unit 8 are different, the slave unit communication device 4 is disconnected during power-off. It is determined that the connection state has been changed, and the display unit 9 displays the increase / decrease of the station number and the type of the slave station. FIG. 5 shows a display example of the increase / decrease of the station number and the type of the slave station. FIG. 5A shows the station number 1 connected last time.
This is a display example of the display unit 9 when the slave stations of (type A station) and station number 2 (station type B) are not recognized. For example, "-1" and "-2" indicate that the station numbers 1 and 2 are not recognized. And the station types A and B are added. FIG. 5B shows a station number 5 (type E station) and a station number 6 which have not been connected previously.
This is a display example of the display unit 9 when a slave station of (type F station) is recognized, and it is determined that the station numbers 5 and 6 are recognized, for example, “+
5 "and" +6 ", and their station types E and F are added. In FIG. 5C, the display unit 9 when the station type of the station number 3 has been changed to D is recognized. Is displayed, for example, "* 3" is displayed to indicate that the station type of the station number 3 has been changed, and the changed station type D is added.

When the contents of the storage unit 5 and the storage unit 8 are different, whether to change the contents of the storage unit 8 is selected by the user. When the switch 10 is pressed, the master station communication device 3 changes the contents of the storage unit 8 to match the contents of the storage unit 5. When the switch 11 is pressed, the storage unit 8
Do not change the contents of When the contents of the storage unit 5 and the storage unit 8 are different, the user can select whether or not to change the contents of the storage unit 8, which is generally effective in a 1: n communication system because the user and the maintenance worker are often different. It is a target. For example, when the user turns on the power, if the information on the transmission line 1 is different from the previous one for some reason and some information is displayed on the master station communication device, the user may find an error in the communication system from the displayed content. Although it is possible to recognize that there is, there is no way to cope with it, so it is necessary when it is necessary to shut down the power while keeping the stored state for the time being. If the power is turned off while keeping the stored state, the same contents as when the user turned on the power will be displayed even if the power is turned on again later when the maintenance worker works. Since the maintenance worker does not need to check the display contents from the user each time, the work efficiency is improved. In such a case, if the user is not informed of the presence of the switch 10 or if processing equivalent to that of the switch 10 can be executed only by a hidden command, the storage unit 8 may be erroneously operated.
Can be prevented from being changed.

After the above-mentioned processing is completed, the master station communication device 3 executes a normal communication process with the slave station communication device 4 on the transmission path 1 based on the contents of the storage unit 5. If the slave station communication device 4 on the transmission path 1 cannot receive the connection confirmation communication data within a certain period of time after the power is turned on in the above-described steps, it is determined that the connection confirmation communication data could not be received for some reason such as noise. Judgment is made, and the station number and the station type are transmitted from the slave station communication device 4 to the master station communication device 3.
At this time, if there is a reply from the master station communication device 3, the slave station communication device 4 proceeds to a normal communication process. The station number and the station type are transmitted to the master station communication device 3 every time.

When the master station communication device receives the station number and the station type data from the slave station communication device 4 even during the normal communication processing, the master station communication device 4 stores the slave station communication device 4 in order to correspond to the operation of the slave station communication device 4 described in the section. The processing is registered in the section 5 and executed. If the slave station communication device 4 on the transmission path 1 cannot receive the connection confirmation communication data within a certain time after the power is turned on,
Transmitting the station number and the station type from the slave station communication device 4 to the master station communication device 3 until there is a response from the master station communication device 3 means that the connection confirmation communication data from the master station communication device 3 is generated by noise or the like. It cannot be received, or the connected slave station information communication data from the slave station communication device 4 is not received by the master station due to noise or the like, or the master station communication device 3 is operating normally and the slave station communication device 4
Is effective in reliably recognizing all the slave station communication devices 4 on the transmission line 1 in order to cope with a case where is reset.

FIG. 6 shows a communication system according to a second embodiment of the present invention. In the present embodiment, the slave station communication device 4-i (i
= 1, 2, 3,..., N) are station number holding units 7-i, respectively.
In addition to (i = 1, 2, 3,..., N), a display unit 12-i capable of displaying the increase / decrease of the station number and the change of the station type respectively.
(I = 1, 2, 3,..., N).

The operation of this embodiment will be described with reference to FIGS. FIG. 7 is a flowchart showing the operation of the master station communication device 3 in the present embodiment, and FIG. 8 is a flowchart showing the operation of the slave station communication device 4-i in the present embodiment.
In the present embodiment, when the contents of the storage unit 5 and the storage unit 8 are different in the above operation, the master station communication device 3 becomes the slave station communication device 4 of the station number recognized as being connected on the transmission line 1.
The slave station communication device 4 communicates the station number and the station type that have increased or decreased, and displays the increase or decrease of the station number and the station type received from the master station communication device 3.

In the slave station communication device 4, the slave station connection information on the transmission line 1 at the time of the previous change and the recognized transmission line 1
The comparison and display of the above-mentioned slave station connection information can be performed, for example, when the master station communication device 3 is out of reach, or when the master station communication device 3 and the slave station communication device 4 are very remote. When the user is at a location, when the user wants to check the connection status of the slave station on the transmission line 1 in the slave station communication device 4, such as when checking the connection of the slave station communication device 4 during construction, the master station communication device 3 is bothersome. There is an effect that the slave station communication device 4 can check the status of the slave station on the transmission path 1 without having to go there.

[0019]

According to the first or second aspect of the present invention, the slave station communication device receives communication data from the master station communication device for its own station number even after a certain period of time has elapsed since the power was turned on. If not, the slave station communication device transmits station number communication data including the station number of the own station to the master station communication device, and if there is a reply from the master station communication device to the station number communication data, Normal communication processing is performed, and if there is no reply from the master station communication device, the station number communication data is repeatedly transmitted at predetermined time intervals until there is a reply. May not be received due to noise, etc., when communication data from the slave station communication device is not received by the master station due to noise, etc., or when the master station communication device is operating normally and the slave station communication device is reset. ,
This is effective in reliably recognizing all slave station communication devices on the transmission path.

According to the third or fourth aspect of the present invention, the station number of the slave station communication device on the transmission line recognized by the master station communication device is compared with the previously stored station number of the slave station communication device on the transmission line. Accordingly, it is possible to recognize whether or not the configuration of the slave station communication device connected to the transmission path has been changed.

According to the invention of claim 5, the station number and the station type of the slave station communication apparatus on the transmission path recognized by the master station communication apparatus, and the station number and station type of the slave station communication apparatus on the transmission path previously stored and Is compared, it is possible to recognize whether or not there has been a change in the configuration of the slave station communication device connected to the transmission path.

According to the sixth aspect of the present invention, it is possible to select whether or not to change the contents of the storage unit. Therefore, even if the user and the maintenance worker are different, if the power is cut off while the storage state is maintained, the maintenance work is performed at a later date. Even if the operator turns on the power again when performing work, the same contents as when the user turns on the power are displayed, and the maintenance worker does not need to check the display contents from the user each time, and the work efficiency is improved. Is improved.

According to the seventh, eighth or ninth aspect of the present invention, the master station communication device compares the slave station connection information on the transmission path at the time of the previous change with the slave station connection information on the recognized transmission path. By displaying, after the communication system is constructed, there is an effect that it is possible to recognize when the power is turned on at the master station that the slave station connection information on the transmission line has changed while the power is off. In particular, when the slave station communication device is located very far from the master station communication device, or when the slave station communication device is not easily reachable, the slave station communication device does not have a display unit and has an apparent appearance. If it is difficult to determine whether it is operating properly or if the number of slave station communication devices is very large,
This is very effective because the master station communication device can recognize the slave station connection information on the transmission path. In this case, since the master station communication device automatically recognizes the slave station communication device on the transmission path, no manual registration work is required.

According to the tenth or eleventh aspect of the present invention, in the slave station communication device, the slave station connection information on the transmission line at the time of the previous change and the slave station connection information on the transmission line recognized by the master station communication device are stored. Since it is displayed by comparison, for example, when the master station communication device is not easily accessible,
When the master station communication device and the slave station communication device are in very remote locations, the slave station communication device checks the slave station connection status on the transmission path, such as when checking the connection of the slave station communication device during construction When the user wants to do so, the slave station communication device can check the status of the slave station on the transmission line without going to the master station communication device.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a communication system according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the master station communication device according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing an operation of the slave station communication device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing registered contents of a storage unit according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram showing display contents of a display unit according to the first embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a communication system according to a first example of the present invention.

FIG. 7 is a flowchart showing an operation of the master station communication device according to the second embodiment of the present invention.

FIG. 8 is a flowchart showing an operation of the slave station communication device according to the second embodiment of the present invention.

FIG. 9 is a schematic configuration diagram of a conventional communication system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission line 2 Termination 3 Master station communication device 4 Slave station communication device 5 Storage unit 7 Station number holding unit 8 Storage unit 9 Display unit 10 Switch 11 Switch

Claims (11)

[Claims] A single master station communication device and one or more slave station communication devices each assigned a unique station number are connected on a transmission path, and a communication between the master station communication device and the slave station communication device is established. In a communication system in which communication is performed based on a station number, the slave station communication device did not receive communication data from the master station communication device for its own station number even after a certain period of time after power-on. In this case, the slave station communication device transmits station number communication data including the station number of the own station to the master station communication device, and if there is a reply to the station number communication data from the master station communication device, normal communication is performed. A communication system for executing a process and repeatedly transmitting station number communication data at predetermined time intervals until a reply is received from the master station communication device if there is no reply from the master station communication device. 2. A single master station communication device and one or more slave station communication devices each assigned a unique station number are connected on a transmission line, and a communication between the master station communication device and the slave station communication device is performed. Communication is performed based on the station number, and the master station communication device transmits the communication data requesting a reply by designating the station number of the slave station communication device on the transmission line, thereby the slave station connected to the transmission line. In a communication system configured to automatically recognize a communication device, the slave station communication device receives communication data from the master station communication device for its own station number even after a certain period of time has elapsed after power-on. If not, the slave station communication device transmits station number communication data including the station number of the own station to the master station communication device, and a reply is returned from the master station communication device to the station number communication data. If normal communication processing is executed,
A communication system characterized by repeatedly transmitting station number communication data at predetermined time intervals until there is a reply from the master station communication device until there is a reply. 3. A single master station communication device and one or more slave station communication devices each assigned a unique station number are connected on a transmission path, and a communication between the master station communication device and the slave station communication device is performed. Communication is performed based on the station number, and the master station communication device transmits the communication data requesting a reply by designating the station number of the slave station communication device on the transmission line, thereby the slave station connected to the transmission line. In a communication system configured to automatically recognize and store a communication device, a station number of a slave station communication device on a transmission line recognized by the master station communication device and a station of the slave station communication device on the transmission line previously stored are stored. A communication system comprising: means for comparing a number with a number to determine whether a configuration of a slave station communication device connected to a transmission path has been changed. 4. The transmission line according to claim 2, wherein the station number of the slave station communication device on the transmission line recognized by the master station communication device is compared with the previously stored station number of the slave station communication device on the transmission line. A communication system comprising means for determining whether or not the configuration of the slave station communication device connected to the communication device has been changed. 5. The slave station according to claim 3, wherein the master station communication device transmits communication data requesting a reply by designating the station number of the slave station communication device on the transmission path, and the slave station connected to the transmission path. By receiving the reply data including the station number and the station type from the communication device, the station number and the station type of the slave station communication device connected on the transmission path are recognized, and the station of the slave station communication device on the recognized transmission path is recognized. By comparing the combination of the number and the station type with the previously stored combination of the station number and the station type of the slave station communication device on the transmission line, whether or not the configuration of the slave station communication device connected on the transmission line has been changed is determined. A communication system comprising: means for determining. 6. The master station communication device according to claim 3, wherein, when the configuration of the slave station communication device connected to the transmission line is changed, whether or not the previously stored content is changed. A communication system comprising: means for selecting 7. The communication system according to claim 3, wherein the master station communication device includes means for displaying information on a change in the configuration of the slave station communication device on the transmission path. 8. A single master station communication device and one or more slave station communication devices, each assigned a unique station number, are connected on a transmission path, and a communication between the master station communication device and the slave station communication device is performed. Communication is performed based on the station number, the master station communication apparatus transmits communication data requesting a reply by designating the station number of the slave station communication apparatus on the transmission path, and the slave station communication apparatus connected to the transmission path. In a communication system configured to recognize and store the station number and station type of a slave station communication device connected on the transmission path by receiving reply data including the station number and the station type from the master station, By comparing the combination of the station number and station type of the slave station communication device on the transmission line recognized by the communication device with the previously stored combination of the station number and station type of the slave station communication device on the transmission line, Of the connected slave station communication device A means for determining whether or not the configuration has been changed; a means for displaying a changed station number and a station type when there is a change; and a means for selecting whether or not to change the previously stored content. A communication system, comprising: 9. A single master station communication device and one or more slave station communication devices each assigned a unique station number are connected on a transmission path, and the master station communication device and the slave station communication device are connected to each other. Communication is performed based on the station number, the master station communication apparatus transmits communication data requesting a reply by designating the station number of the slave station communication apparatus on the transmission path, and the slave station communication apparatus connected to the transmission path. In a communication system configured to recognize and store the station number and station type of a slave station communication device connected on the transmission path by receiving reply data including the station number and the station type from the master station, By comparing the combination of the station number and station type of the slave station communication device on the transmission line recognized by the communication device with the previously stored combination of the station number and station type of the slave station communication device on the transmission line, Of the connected slave station communication device A means for determining whether or not the configuration has been changed, a means for displaying a changed station number and a station type when a change has been made, and a means for selecting whether or not to change the previously stored content. If the slave station communication device does not receive communication data from the master station communication device for its own station number even after a certain period of time has elapsed after power-on,
The slave station communication device transmits station number communication data including the station number of the own station to the master station communication device, and executes a normal communication process if the master station communication device returns a reply to the station number communication data. A communication system characterized by repeatedly transmitting station number communication data at predetermined time intervals until a reply is received from the master station communication device if there is no reply. 10. A communication device according to claim 3, wherein the information on the change of the configuration of the slave station communication device on the transmission line recognized by the master station communication device is transmitted to one or more slave station communication devices on the transmission line. The slave station communication device comprises means for displaying information received from the master station communication device. 11. The slave station communication device according to claim 7, wherein the master station communication device includes means for displaying information relating to a change in the configuration of the slave station communication device on the transmission path. Transmitting information related to the change of the configuration from the master station communication device to one or more slave station communication devices on the transmission path, wherein the slave station communication device includes means for displaying information received from the master station communication device. A communication system characterized by the following.