JPH0675612A - Office number duplication testing method for programmable controller - Google Patents

Abstract

PURPOSE:To prevent a malfunction due to the office number duplication of a data link system by securely testing the duplication or absence of the office number of the data link. CONSTITUTION:A master station sends a command frame to a station with a specified office number and the station receives the command frame, sets the gate of a line driver to 'H' and waits for a certain time, and sends a response frame and then sets the gate of the line driver to 'L' with the lapse of a certain time. If the office number is duplicate, the response is not received normally by the master station and a time-out state is entered; and then the master station sends a command frame to itself to efficiently detect whether the station (tested office number) is present or duplicate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a station number duplication test method for a programmable controller having a function of forming a data link by a bus type topology, and a programmable controller for communicating data via a network unit in the form of a bus transmission path. To a programmable controller station number duplication test method using a programmable controller network.

[0002]

2. Description of the Related Art FIG. 18 is a block diagram showing a hardware configuration of a programmable controller having a data link function. In FIG. 18, 1 is a link control unit that controls a data link, 1a is a CPU that controls the link control unit 1, and 1b is a communication interface (I / I) for transmitting and receiving link data from a line.
F) 1c is a micro ROM for storing the software of the link control unit 1 and 1d is an RA for storing the link data received from the line or the link data transmitted to the line.
M and 1e are 2-port RAMs for interfacing with the sequence control unit 2.

Reference numeral 2 is a sequence control unit for controlling a sequence program and an input / output unit, and 2a
Is a CPU for controlling the sequence control unit 2, 2b is a micro ROM for storing the software of the sequence control unit 2, 2c is a RAM for temporarily storing the operation result of the sequence program and other information, 2d is an input / output unit An input / output interface (I / F) for exchanging input / output ON / OFF information, and a peripheral device interface (I / F) 2e for exchanging information with peripheral devices.
F) and 2f are memories for storing the sequence program.

FIG. 19 is a circuit diagram showing a detailed structure of the communication interface (I / F) 1b shown in FIG. 18. In FIG. 19, 3a and 3b are line drivers for outputting to a data line, and A line receiver for inputting data from the line is shown.

FIG. 20 is a block diagram showing a schematic configuration of a data link system of a programmable controller having the data link function shown in FIG. 18. In FIG. 20, two stations 5a and 5b are mistakenly duplicated in their station numbers. It shows an example.

FIG. 21 is a flow chart showing the processing operation of the 1 station (master station) 4 shown in FIG. 20, and FIG. 22 is the 2 station, 4 station (slave station) shown in FIG. It is a flow chart which shows processing operation of 5a, 5b, and 5c. Further, FIG. 23 is a timing chart showing a state in which the slave station can simultaneously process a command frame from the master station, and FIG. 24 shows the slave station in processing a command frame from the master station. It is a timing chart which shows a state when there is a time difference.

Next, the processing operation of the master station 4 configured as shown in FIG. 20 will be described with reference to the flowchart of FIG. 21, and the processing operation of the slave stations 5a and 5b will be described with reference to the flowchart of FIG. To do.

As shown in FIG. 21, the master station 4 sets the gate E of the line driver 3a to "H" to transmit data.
(Active) ”(S115). Next, the command frame is transmitted to the slave stations 5a and 5b (S11).
6) The gate E of the line driver 3a is set to "L (inactive)" to end the data transmission (S11).
7).

Next, as shown in FIG. 22, the slave station 5
When a and 5b determine that the reception of the command frame is completed (S122), the gate E of the line driver 3b is set to "H" (S123), and a response frame for notifying the completion of reception to the master station is transmitted. (S12
4). Then, the gate of the line driver 3b is set to "L" (S125). However, slave stations 5a and 5b
The processing of the master station 4 is different depending on whether the reception completion timings are the same (see FIG. 23) or different (see FIG. 24).

Here, when the reception completion (S118) timings of the slave stations 5a and 5b are the same, the processing as shown in FIG. 23 is performed. That is, the slave stations 5a and 5b
Sets the gate E to "H" for each and sends a response frame to the master station 4. At this time, since there are a plurality of slave stations (5a, 5b), the outputs of the stations (5a, 5b) in the "H" state on the line collide, and the master station 4 cannot receive the response frame normally. , The waiting time is up (S119), and abnormal communication occurs (S
121). On the contrary, in step 118, when the reception completion timings of the slave stations 5a and 5b are different, the processing is as shown in FIG. That is, since the slave station 5a has completed the reception before 5b, it transmits the response frame. The slave station 5b transmits the response frame to the master station 4 later than 5a. The master station 4 can receive the response frame of the slave station 5a transmitted first, and normally complete the communication with the slave station (communicate normally) (S120).

In addition, as a reference technical document related to the present invention, "Network address test method" disclosed in JP-A-2-230840, JP-A-2-
-170637, "Communication station address automatic setting method", "Address confirmation method", disclosed in JP-A-1-192241, JP-A-2-290
"Network system and method for testing duplicate address" disclosed in Japanese Patent No.
"Station address check processing method" disclosed in Japanese Patent No. 345, "Address duplication detection method" disclosed in Japanese Patent Laid-Open No. 61-287349, Japanese Patent Laid-Open No. 2-108.
No. 341, “Station address duplication setting detection method”, Japanese Patent Laid-Open No. 3-267845, “Data transmission system”, Japanese Patent Laid-Open No. 4-33433.
"Unauthorized address management method" disclosed in Japanese Patent Laid-Open No. 4-84537, "Duplicate node address detection method for data transmission system" disclosed in Japanese Patent Laid-Open No. 4-84537,
There is a "LAN interconnection device" disclosed in Japanese Patent Laid-Open No. 200131.

[0012]

In the conventional bus-type topology data link system, the processing of the master station is different depending on whether the reception completion timings in the slave stations are the same or different, as described above. There is a problem in that the duplicated station number cannot be detected normally, resulting in a malfunction due to the duplicated station number of the data link system / network system.

The present invention has been made in order to solve the above problems, and makes it possible to reliably test the duplication or omission of the station number of a data link in a bus type topology system, and to realize a data link system. A first object is to obtain a programmable controller station number duplication test method capable of preventing malfunction due to station number duplication.
The purpose of.

Further, according to the present invention, it is possible to surely test the duplication or omission of the station number setting of each unit via the network unit in the form of a bus transmission line, thereby preventing the malfunction caused by the duplication of the station number of the network system. A second object is to obtain a programmable controller station number duplication test method.

A third object of the present invention is to obtain a programmable controller station number duplication test method which prevents a duplicate station having a station number setting in a bus transmission line from malfunctioning and adversely affecting the entire system.

A programmable controller for automatically re-establishing a duplicated station having a station number setting in the bus transmission line mode when the duplication error disappears by unconstraining or correcting the setting to improve the operation efficiency of the programmable controller. A fourth object is to obtain the station number duplication test method of.

Further, it is possible to measure the number of duplicated stations in the station number setting in the bus transmission line form, correct the setting of the duplicated stations early, and prevent malfunction due to duplicated station numbers in the network system. A fifth purpose is to obtain a test method.

[0018]

A station number duplication test method for a programmable controller according to the present invention is a station number duplication test method for a programmable controller having a function of configuring a data link by a bus type topology, during data link communication. Any station is designated as a station (master station) to execute the station number duplication test, a station to be tested (slave station) is designated, the master station sends a command frame to the slave station, and the slave station sends a command. Receives a frame, sets the gate of the line driver to "active" and waits for a certain period of time, sends a response frame and waits for a certain period of time, sets the gate of the line driver to "non-active", and duplicates the slave station If so, the response frame is normally received by the master station. Is not timed out, the master station transmits a command frame of the receiving apparatus after a timeout, whether slave station exists by determining whether or not it received correctly, it is to determine whether the slave station is duplicated.

Further, in the station number duplication test method of the programmable controller having the function of forming the data link by the bus type topology, an arbitrary station is set as a station (master station) for executing the station number duplication test before the data link communication is started. As a station (slave station) that designates and tests all stations configuring the data link, the master station transmits a command frame to the slave station, the slave station receives the command frame, and the line driver If the gate is set to “active” and waits for a certain time, the response frame is transmitted and waits for a certain time, the gate of the line driver is set to “non-active”, and if the slave stations are duplicated, the response frame Is not normally received by the master station and has timed out. Sends a command frame of the receiving apparatus after a timeout, whether slave station exists by determining whether or not it received correctly, it is to determine whether the slave station is duplicated.

The programmable controller uses a programmable controller network that communicates data via a network unit in the form of a bus transmission line, and an arbitrary station is designated as a station (master station) for executing a station number duplication test. A test message is sent from a station to a test station (slave station), and it is detected whether the station number of the slave station is duplicated or the slave station exists depending on the reception status of the response message from the slave station. Is.

Further, when it is detected that the station numbers of the slave stations are duplicated according to the reception status of the response message from the slave station, the slave stations having the duplicated station numbers cannot be transmitted. .

Further, the programmable controller is tested by designating an arbitrary station as a station (master station) for executing the station number duplication test by using a programmable controller network that communicates data via a bus transmission line type network unit. When a station (slave station) is designated and a station number duplication station is detected, a test is periodically executed from the master station to the slave station having the station number duplication, and when the duplication error disappears, automatic recovery is performed.

Further, the programmable controller uses a programmable controller network that communicates data via a network unit in the form of a bus transmission line, tests the setting state of the station number of each programmable controller from an arbitrary station, and the station number is duplicated. The number of duplicate stations is measured.

[0024]

In the station number duplication test of the programmable controller according to the present invention, the master station transmits the command frame to the designated station number. The station number receives the command frame, sets the gate of the line driver to "H", waits for a fixed time, transmits the response frame, waits for a fixed time, and then sets the gate of the line driver to "L". If the station number is duplicated, the response is not normally received by the master station and times out, and the master station sends a command frame to itself and then the station (tested station number) exists.
Efficiently detect whether station numbers are duplicated.

Further, the station number duplication test is executed by using all the stations forming the data link as slave stations.

Further, the master station transmits a command frame to the designated station number. The slave station receives the command frame and sends a response to the master station.
The master station efficiently detects whether the slave stations are overlapping or missing depending on the reception status.

[0027]

【Example】

[Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows one station (master station) shown in FIG.
4 is a flowchart showing the processing operation of No. 4, showing the processing of the master station. 2 is a flowchart showing the processing operation of the two stations (slave stations) 5a and 5b shown in FIG. 20 and shows the processing of the slave station. Further, FIGS. 3, 4 and 5 are timing charts of the station number duplication test process shown in FIG.

The operation of the first station (master station) 4 in this embodiment shown in FIG. 20 is referred to the flow chart shown in FIG. 1, and the operation of the second station (slave stations) 5a and 5b is shown in FIG. This will be described below with reference to the flowchart.

As shown in the flowchart of FIG. 1, the first station (master station) 4 sets the gate of the line driver 3a of the first station (master station) 4 to "H" (S1). Next, the command frame 1 is transmitted to the station number 2 (S2), and the gate of the first station (master station) 4 is set to "L" (S3).

When the two stations (slave stations) 5a and 5b judge that the command frame has been received (S15a), as shown in the flowchart of FIG. 2, the slave station 3b.
Is set to "H" (S15) and waits for a time (S16). The meaning of this waiting time is that the reception timing may be different for the same station number, so by waiting for a time, it is possible to cope with different reception timings. This time is the response pre-transmission gate “H” time t _{3 shown} in FIGS. After waiting the time of step 16 above, a response frame is transmitted to the 1 station (master station) 4 (S17) and waits for the time (S1).
8). In this waiting time, when the 1 station (master station) 4 cannot normally receive the response frame, the 1 station (master station) 4 transmits the command frame to itself,
It is waiting for the time to determine whether the station number is duplicated or not. This time is the gate "H" time t ₄ after the response transmission shown in FIGS. After waiting the time of step 18, the gates of the slave stations 5a and 5b are set to "L" (S
19).

Returning to FIG. 1, the first station (master station) 4 waits for reception until the time is up to judge whether or not there is an abnormality in the station number (S4). Here, when there is one slave station, that is, when the station number is normally set, reception is possible and the processing ends normally (S6). However, in this embodiment, there are two slave stations, 5a and 5b. As shown in the timing chart of FIG. 4, since the gate 3b becomes “H” at two points at the same timing, one station (master station) 4
Cannot receive normally, and the reception waiting time is up (S5). The first station (master station) 4 communicates with its own station in order to increase the reception waiting time. After that, the gate is set to "H" (S7), the command frame 2 is transmitted to the own station (S8), and then the gate is set to "L" (S).
9).

Next, the first station (master station) 4 waits for reception (S10), and when it judges that it has not received, it further judges whether or not the reception waiting time is up (S11). Here, as shown in the time chart of FIG. 4, the slave station 5
1 station (master station) 4 because the gates of a and 5b are "H"
The command frame 2 output from the device collides on the line, and the first station (master station) 4 cannot receive it normally.
This makes it possible to determine that the tested station number 2 is an abnormal station number duplication (S13). After it is determined that there is an abnormality, the process waits for a time (S14), and the series of processes is ended. This waiting time is the time until the gate of the tested station is set to "L" and is the waiting time t ₂ shown in FIGS. 3, 4 and 5.

A case in which the same test as above is performed on the station number 3 which does not exist will be described. The first station (master station) 4 transmits the command frame to the station number 3 (not present). However, since there is no slave station, the first station (master station) 4 cannot receive the response frame and the reception time is up (S4, S5).
The first station (master station) 4 performs the same process as above, and the first station (master station) 4 waits for reception (S10, S1).
1). Therefore, as shown in the timing chart of FIG. 5, since there is no slave station, one station (master station) 4
No gate is set to "H" other than the gates, and the command frame 2 transmitted to the local station is normally received.

As described above, since the response frame from the slave station cannot be received and the command frame 2 to the local station can be received, it can be confirmed that the station number 3 is an abnormal station number omission (none) (S12).

[Second Embodiment] Next, a second embodiment according to the present invention will be described. The above-described first embodiment is executed for the designated station (one station). However, as shown in the flowchart in FIG.
24) for all linked stations (S26, S
27), the station number duplication test described in the first embodiment is executed (S25), and after the test is completed, the test result is returned to the peripheral device via the peripheral device interface (I / F) 2e shown in FIG. Yes (S28).

[Embodiment 3] Next, a third embodiment of the present invention will be described. FIG. 7 is a flowchart showing the processing operation of the station number duplication test of the one station (master station) 4 shown in FIG. 20, showing the processing of the master station. Also, FIG.
FIG. 21 is a flowchart showing the processing operation of a station for which the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 is performed, showing the processing of the slave station. In addition, FIG.
10 is a timing chart showing the timing when the station numbers do not overlap, and FIG. 10 is a timing chart showing the timing when the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 is executed. Is. FIG. 11 shows a communication interface of each station, which is composed of a line driver 51, a line receiver 52, and a duplicate transmission detection circuit 53. The line driver 51 activates the gate only when the time station transmits, and is normally inactive. Further, the line receiver 52 is always set to be active so that it can always receive the data of the transmission line.

In the processing of the master station which is the station number duplication test execution station, as shown in FIG. 7, the gate of the line driver 51 of the first station (master station) 4 is set to active (S2
9) Obtain the transmission right. Next, after transmitting the test message to the n stations of the test station (S30), the master station sets the gate of the line driver 51 to inactive (S31) and releases the transmission right. After that, the monitoring timer is set until the response of the slave station is received (S32), and the response reception state of the slave station is monitored. When the duplicated transmission detection circuit 53 shown in FIG. 11 detects a duplicated transmission error signal (S33), the abnormal reception number is set to +1 (S36), and it is stored that the duplicated station exists.

When the response message is normally received from the slave station (S34), the number of normal receptions is incremented by 1 (S37). After that, when the monitoring time that can surely receive the response from the slave station has elapsed (S35),
The monitoring timer is reset (S38) and the reception state is checked. As a checking method, if the number of abnormalities is other than 0 (S39), it is determined that a slave station duplication error occurs (S4).
4). When the abnormal count is 0 and the normal count is 0 (S4
1), there is no slave station (S43). The number of abnormalities is 0
If the number of normal times is 1 (S40), the slave station is normal and there is no duplicate station (S42).

Next, in the process of the slave station, as shown in FIG. 8, it is checked whether or not the message is addressed to the own station (S45), and if the message is addressed to the own station, a response frame (data) is created (S46). , The line driver 51 is set active (S47), and the transmission right is acquired. Then, after waiting for time t2 (S48), it is checked whether or not the duplicated transmission detection circuit 53 of the own station shown in FIG. 11 has detected the duplicated transmission error signal (S49). Since there is no station, the response frame is sent to the master station (S5
2) After waiting for time t3 (S53), the transmission gate of the line driver 51 is deactivated (S5).
1) Release the transmission right.

In the above test, FIG. 9 shows the timing when the station numbers of the 4 stations 5c shown in FIG. 20 do not overlap. In addition, the two stations (slave stations) 5a shown in FIG.
5 shows the timing when there is an overlapping station of 5b.

[Fourth Embodiment] Next, a fourth embodiment according to the present invention will be described. The flow chart of the master station showing the processing operation of the station number duplication test of the one station (master station) 4 shown in FIG. 20 is the same as that shown in FIG. 7 of the third embodiment, and the station numbers are duplicated. 2 stations (slave station) shown in the timing chart and Fig. 20 when there is no such station
Timing charts when the station number duplication test of 5a and 5b is executed are shown in FIG. 9 and FIG.
It is the same as that shown in 0. Further, the communication interface shown in FIG. 11 is used. FIG. 12 is a flow chart showing the processing operation of the stations to be subjected to the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG.

The processing of the master station which is the station number duplication test execution station is the same as the processing shown in FIG. 7 in the third embodiment. Next, the processing of the slave station is as shown in FIG.
Check whether the test message is a message addressed to your own station (S5
4) If the message is addressed to the own station, check the flag whether a station number duplication error was detected in the previous test (S5
5) When an error is being detected, nothing is transmitted from the slave station thereafter. When no error is detected, a response frame (data) is created (S56), the line driver 51 is set to active (S57), and the transmission right is acquired. After waiting for time t2 (S58), it is checked whether or not the duplicated transmission detection circuit 53 of its own station shown in FIG. 11 has detected the duplicated transmission error signal (S59). If it is normal, there is no duplicated station. Therefore, the response frame is sent to the master station (S
63), after waiting for time t3 (S64), the transmission gate of the line driver 51 is deactivated (S6).
2). When the station number duplication error is detected in this way, the slave stations do not simultaneously perform data transmission thereafter, so that the entire system is not adversely affected. When the duplicate transmission error signal is detected in step 59, the station number duplication error flag is set (S60), and after waiting for time rt + t3 (S61), the line driver 51 is set.
The transmission gate of is made inactive (S62).

[Fifth Embodiment] Next, a fifth embodiment according to the present invention will be described. 13 is the same as that shown in FIG.
It is a flow chart which shows the processing operation of the station number duplication test of the station (master station) 4, and shows the processing of the master station. The flowchart showing the processing operation of the stations to be subjected to the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 is the same as that shown in FIG. Indicates processing. Also, the timing chart when the station numbers do not overlap and the two stations (slave stations) shown in Fig. 20.
Timing charts when the station number duplication test of 5a and 5b is executed are the same as those shown in FIGS. 9 and 10 shown in the third embodiment. Further, the communication interface in each station shown in FIG. 11 is used.

The process of the master station which is the station number duplication test execution station checks whether or not the station number duplication test is the first time as shown in FIG. 13 (S65). The gate of the line driver 51 of the master station 4 is set active (S67), and the transmission right is acquired. Next, after transmitting the test message to the n stations of the test station (S68),
The master station sets the gate of the line driver 51 to inactive (S69) and releases the transmission right. After that, the monitoring timer until the response of the slave station is received is set (S70), and the response reception state of the slave station is monitored. When the duplicated transmission detection circuit 53 shown in FIG. 11 detects a duplicated transmission error signal, the number of abnormal reception is +
It is set to 1 (S74), and it is stored that there is an overlapping station.

When the response is normally received from the slave station (S72), the number of normal receptions is incremented by 1 (S75). When the monitoring time period during which the response from the slave station can be reliably received has elapsed (S73), the monitoring timer is reset (S76) and the reception state is checked.
If the number of abnormalities is other than 0 (S77), the check method is
A slave station duplication error is determined (S84). If the number of abnormalities is 0 and the number of normal times is 0 (S79), there is no slave station (S82), and the station number duplication error flag is set (S).
83). When the abnormal count is 0 and the normal count is 1 (S7
8), normalize the slave station (S80), and reset the station number duplication error flag (S81).

The master station is the second and subsequent tests (S65)
Checks the station number duplication error flag (S66), and if there is an error, repeats the above process, and the master station periodically performs the above process on the slave stations with station number duplication to eliminate duplication error. When the error occurs, the error station is automatically restored. 2 stations (slave station) 5 shown in FIG.
The flow chart showing the processing operation of the stations to be subjected to the station number duplication test of a and 5b is the same as that shown in FIG. 8 of the third embodiment and shows the processing of the slave station. Further, the timing chart when the station numbers do not overlap and the timing chart when the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 are performed are shown in FIGS. Is the same as that shown in. In addition, FIG.
Use the communication interface of each station shown in.

[Sixth Embodiment] Next, a sixth embodiment according to the present invention will be described. 15 is the same as that shown in FIG.
It is a flow chart which shows the processing operation of the station number duplication test of the station (master station) 4, and shows the processing of the master station. FIG.
FIG. 21 is a flowchart showing the processing operation of a station for which the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 is performed, showing the processing of the slave station. The timing chart when the station numbers do not overlap is the same as that shown in FIG. 9 of the third embodiment, and the station number duplication test of the two stations (slave stations) 5a and 5b shown in FIG. 20 is performed. The timing chart in the case of turning on is the same as that shown in FIG. Further, the communication interface of each station shown in FIG. 11 is used.

As shown in FIG. 15, the processing of the master station of the station number duplication test execution station sets the gate of the line driver 51 of the first station (master station) 4 to active (S8).
5) Obtain the transmission right. Next, after transmitting the test message to the n stations of the test station (S86), the master station sets the gate of the line driver 51 to inactive (S87) and releases the transmission right. After that, a monitoring timer until the response of the slave station is received is set (S88), and the response reception state of the slave station is monitored. When the duplicate transmission detection circuit 53 shown in FIG. 11 detects the duplicate transmission error signal (S89), the number of abnormal reception is incremented by 1 (S92),
Remember that there are duplicate stations.

When the response message is normally received from the slave station (S90), the normal reception number is incremented by +1.
(S93). When the monitoring time that can surely receive the response message from the slave station has elapsed (S91),
The monitoring timer is reset (S94) and the reception state is checked. As a checking method, if the number of abnormal receptions is 0 (S95), a slave station duplication error is determined (S10).
0), the number of normal receptions is set as the number of duplicate stations (S101). If the abnormal reception count is 0 and the normal reception count is 0 (S9
In the case of 7), there is no slave station (S99). If the abnormal reception count is 0 and the normal reception count is 1 (S9
6) The slave station is set to normal (S98). If the number of abnormal receptions is not 0, the test fails as a protocol error (S102).

Next, in the processing of the slave station, as shown in FIG. 10, it is checked whether or not the message is addressed to the own station (S103), a response frame (data) is created (S104), and the line is transmitted. The driver 51 is set to active (S105) and a transmission right is requested. When the duplicate transmission error signal cannot be detected (S106) and the transmission right is obtained, after waiting for time t2 (S111), the response frame is transmitted to the master station (S112) and waiting for time t
After 3 (S113), the transmission gate of the line driver 51 is made inactive (S114). If the transmission right is not obtained, the transmission gate is deactivated (S107), and waits t2 hours until the station having the transmission right finishes transmitting the response (S108), and the reception of the rod-shaped material and the response message is completed. It is judged whether or not (S
109), wait for time t3 (S110), activate the gate again (S105), and request the transmission right.
This process is repeated until the transmission right is obtained. Also, in these tests, the two stations (slave stations) 5a and 5b in FIG.
FIG. 17 shows the timing in the case where there is an overlapping station.

[0051]

As described above, according to the present invention, in the station number duplication test of the bus-type data link system, the designated station communicates with a certain station number, and when the communication cannot be performed normally, the designated station again makes its own station. On the other hand, there is an effect that it is possible to dramatically improve the work efficiency by determining whether the station number is missing or the station number is duplicated by performing communication.

Further, according to the present invention, in a system in which data communication is performed via a network unit in the form of a bus transmission line, a designated station communicates with a certain station number, and when communication cannot be performed normally, the designated station is re-established. By communicating with itself, it is possible to determine whether the station number is missing or the station number is duplicated, and it is possible to dramatically improve the work efficiency.

[Brief description of drawings]

FIG. 1 is a flowchart showing a station number duplication test processing operation of a master station according to the present invention.

FIG. 2 is a flowchart showing a processing operation of a slave station according to the present invention.

FIG. 3 is a timing chart showing a station number duplication test process.

FIG. 4 is a timing chart showing a station number duplication test process.

FIG. 5 is a timing chart showing a station number duplication test process.

FIG. 6 is a flowchart showing a station number duplication test processing operation of a master station according to another embodiment of the present invention.

FIG. 7 is a flow chart showing the processing operation of the master station of the station number duplication test according to the present invention.

FIG. 8 is a flowchart showing a processing operation of a slave station in the station number duplication test according to the present invention.

FIG. 9 is a timing chart of a normal station number duplication test.

FIG. 10 is a timing chart at the time of abnormality in the station number duplication test.

FIG. 11 is a circuit diagram showing a schematic configuration of a communication interface of the programmable controller according to the present invention.

FIG. 12 is a flowchart showing a processing operation of a slave station in the station number duplication test according to the present invention.

FIG. 13 is a flowchart showing the processing operation of the master station in the station number duplication test according to the present invention.

FIG. 14 is a flowchart showing the processing operation of the master station of the station number duplication test according to the present invention.

FIG. 15 is a flowchart showing the processing operation of the master station in the station number duplication test according to the present invention.

FIG. 16 is a flowchart showing a processing operation of a slave station in the station number duplication test according to the present invention.

FIG. 17 is a timing chart showing the timing when the station number duplication test according to the present invention is abnormal.

FIG. 18 is a block diagram showing a hardware configuration of a programmable controller having a data link function.

19 is a circuit diagram showing details of a communication interface in the programmable controller shown in FIG.

FIG. 20 is a block diagram showing a configuration of a bus type data link system.

FIG. 21 is a flowchart showing a data link processing operation of a conventional master station.

FIG. 22 is a flowchart showing a conventional data link processing operation of a slave station.

FIG. 23 is a timing chart showing a conventional data link process.

FIG. 24 is a timing chart showing conventional data link processing.

[Explanation of symbols]

 1 Link control unit 2 Sequence control unit 3 Duplicate transmission detection circuit 3a Master station line driver gate 3b Slave station line driver gate 4 Master station 5a Slave station 5b Slave station 51 Line driver 52 Line receiver 53 Duplicate transmission detection circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masakatsu Nagase 5107-1071, Kamie 5-chome, Higashioosone-cho, Kita-ku, Nagoya-shi Mitsubishi Electric Mechatronics Software Co., Ltd.

Claims (6)

[Claims] 1. A station number duplication test method for a programmable controller having a function of forming a data link by a bus type topology, during data link communication.
Any station is designated as a station (master station) to execute the station number duplication test, a station to be tested (slave station) is designated, the master station sends a command frame to the slave station, and the slave station sends a command. Receives a frame, sets the line driver gate to "active" and waits for a certain period of time, sends a response frame and waits for a certain period of time, and sets the line driver gate to "non-active"
If the slave stations are duplicated, the response frame is not normally received by the master station and times out, and after the timeout, the master station sends a command frame addressed to itself and can receive correctly. A station number duplication test method for a programmable controller, which is characterized by determining whether a slave station exists or whether a slave station is duplicated. 2. In a station number duplication test method for a programmable controller having a function of configuring a data link by a bus type topology, an arbitrary station is set as a station (master station) that executes a station number duplication test before starting data link communication. As a station (slave station) that designates and tests all stations configuring the data link, the master station transmits a command frame to the slave station, the slave station receives the command frame, and the line driver Set the gate to "active" and wait for a certain time,
After transmitting a response frame and waiting for a certain period of time, setting the gate of the line driver to “non-active”, and if the slave stations are duplicated, the response frame is not normally received by the master station and a timeout occurs, The master station transmits a command frame addressed to itself after a timeout, and determines whether there is a slave station or whether slave stations are duplicated depending on whether or not it can correctly receive the station frame number of the programmable controller. Duplicate test method. 3. A programmable controller network for communicating data through a programmable controller via a network unit in the form of a bus transmission path,
Designate any station as the station (master station) that executes the station number duplication test, send a test message from the master station to the test station (slave station), and check the reception status of the response message from the slave station. A station number duplication test method for a programmable controller, characterized by detecting whether station numbers of slave stations are duplicated or whether slave stations exist. 4. When it is detected that the station numbers of the slave stations are duplicated according to the reception status of the response message from the slave station, the slave stations having the duplicated station numbers are prevented from transmitting. The station number duplication test method for a programmable controller according to claim 3. 5. A programmable controller network for communicating data through a programmable controller via a network unit in the form of a bus transmission path,
When an arbitrary station is designated as the station (master station) that executes the station number duplication test, the station (slave station) to be tested is designated, and when a station number duplication station is detected, the master station periodically sends it to the slave station with the station number duplication. A method of testing the station number duplication of a programmable controller, which is characterized in that when the duplication error disappears, the automatic recovery is performed. 6. A programmable controller network for communicating data through a programmable controller via a network unit in the form of a bus transmission line,
A station number duplication test method for a programmable controller, characterized in that the station number setting state of each programmable controller is tested from an arbitrary station and the number of duplicate stations having the same station number is measured.