JPS6025345A - Address check system of loop transmission system - Google Patents

Abstract

PURPOSE:To prevent the duplication of addresses by setting the address to each transmission controller and checking whether or not a transmission controller having the same address in a transmission system exists. CONSTITUTION:The transmission controllers fed with an address each in advance are connected to constitute a loop transmission line, each transmission controller transfers a received message to a next transmission controller and the message circulated in the loop transmission line is deleted at the transmission controller being the transmitting source. In order to check the duplication of each address, each transmission controller transmits an address train message at the activation of the own device and at the release of a detour, and each transmission controller receiving the address train message adds sequentially the own address thereto and transmits the result to the transmission line. The transmission controller being the transmitting source analyzes the address train in the circulated message and checks whether or not there is an identical address to the own address.

Description

[Detailed Description of the Invention] [Advantageous Field of the Invention] The present invention is inspired by an address check method for a loop transmission system, and checks whether there is a duplicate address assigned to each transmission control device in the patented loop transmission system. This relates to a method of checking whether or not the above is true.

[Background of the invention]

In conventional loop transmission systems, one of the multiple transmission control devices connected to the loop is a mask transmission control device, and this mask transmission control device grasps the transmission status of the entire loop and controls the transmission and reception timing. I was taking measures to troubleshoot the loop. However, if the mask transmission control device fails, transmission becomes impossible, so the present inventors proposed a loop transmission system that does not use the mask transmission control device (for example, Japanese Patent Laid-Open No. 56-40344 and Japanese Patent Application No. 55-12596
(See specification No. 5).

In the method disclosed in the above-mentioned Japanese Patent Application Laid-open No. 56-40344, when the loop transmission path becomes abnormal, each transmission control device on the loop transmits a message containing a command to check the transmission availability of the small loop, and When each of the above transmission control devices receives the message, it transfers the message to the next one, and also issues a transmission permission check command from itself to check whether or not small loop transmission is possible.

However, in the loop transmission system described above, it is assumed that the addresses assigned to each transmission control device are all different, so a newly started transmission control device or a transmission control device that has recovered from a failure is If the address is the same as that of the transmission control device, there is problem R that cannot be handled and the transmission becomes incomplete.

On the other hand, in the system shown in the above-mentioned Japanese Patent Application No. 55-125965, each transmission control device performs a small loop check without an address, forms a detour when a failure is detected, and also forms a large loop without an address.・Check and
When the loop recovery is detected, the detour is canceled. Then, addresses are automatically set for newly added transmission control devices for which addresses have not been set and for transmission control devices that have recovered from a failure, so that there is no duplication of addresses for each transmission control device.

However, in the above method, an arbitrary Kv is set so that the address of each transmission control device does not overlap with other addresses, and the set address is detected by the host processing device, so the Kv
requires the addition of new functions and poses maintenance problems. For this reason, a method in which addresses are set in advance for each transmission control device is easier to control and is preferable, but in this case, the button will have multiple transmission control devices with the same address installed in the transmission system. There is a possibility that this may occur, and countermeasures must be taken to prevent this.

[Purpose of the invention]

The purpose of the present invention is to solve such conventional problems and to (1) set an address in advance to each transmission control device, and check whether there are multiple transmission control devices with the same address in the transmission system. An object of the present invention is to provide an address check method for a loop transmission system that allows message transmission to occur normally.

[Summary of the Invention] In the address check method of the loop transmission system according to the present invention, an address is assigned to each transmission control device in advance, a detour is formed in the event of a failure, and messages that have gone around the loop transmission path are transmitted under the transmission control of the sender. In a loop transmission system that is erased by a device, each transmission control device transmits an address train message when it starts up and when it cancels a detour, and each transmission control device that receives the address train message sequentially erases itself. The transmission control device of the sender analyzes the address string in the message and checks whether there is a transmission control device with the same address as the message itself. There is.

[Embodiments of the invention]

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

FIG. 1 is an overall configuration diagram of a loop transmission system to which the present invention is applied.

The loop transmission system is provided with loop transmission lines 1 and 2, which mutually transmit reverse VC information as shown by arrows. On the loop is a transmission control device (hereinafter referred to as NCP).
11 to 14.21 to 24 are installed, and a pair of N(1'
P11, 21.12, 22°13, 23.14 and 24 are connected to each other by detours 41-44, and 51-54. In addition, one button for each NCP is connected to the host processing device ff3.
l-34 is a bidirectional transmission line (61, 71), (62, 7
2), (63,73).

(64, 74).

FIG. 2 is a diagram showing the arrangement within one message transmitted by the loop transmission system of FIG.

In Figure 2, 51 and 56 are flags [F] indicating the beginning and end of the message, 52 is a function code (FC) - a code corresponding to the content and function of the data, and 53 is the code of the NCP that created and sent the message. address (source address S
A), 54 is data (]) ata) T:, information to be processed, and 55 is error detection data (FC3).

FIG. 3 is an explanatory diagram of the operation of the loop transmission system to which the present invention is applied in a normal state.

Assume that the NCP 21 sends a message 401f to the loop 2 in a state where there is no KM in the loop transmission system.

In this case, the NCP 21 sets its own NCP address N□ in the SA section (see 53 in FIG. 2) of the message 401.

When the NCP 21 receives the message 401 that has made one circuit around the loop transmission path 2, it detects that it is self-originated data because the SA part in the message matches the own NCP address N1, and does not relay it. Then, since retransmission is no longer necessary, the message 401 stored in the own NCP is deleted.

In this way, the data that has gone around the transmission system is sent to the source NC.
Disappeared by P.

FIG. 4 is an explanatory diagram of the operation of a loop transmission system (when a failure occurs) to which the present invention is applied.

Suppose now that a failure occurs in the transmission path between NCPs 22 and 23 and NCPs 12 and 13, making transmission impossible (Failure A).

At this time, Momobi NCP21 sends message 40 to loop 2.
2, this message 402 will not be returned to the NCP 21 due to the late fiA. The NCP 21 detects that there is a KM error on the transmission path when the data transmitted by itself does not return even after a period of time T has elapsed, and it becomes the transmitter and transmits the small loop check signal 301. . Furthermore, NCP21 against NCPII,
Requests to send a small loop check message @303. NCP 22, which received the small loop check signal 301 from NC'P 21, sends the signal to NeP 12 and itself becomes the source and sends the small loop check signal 302, but the Therefore, this faith-8
・does not return to N CP 22. Similarly, N
CP 16.15.14 also small loop check signal 3
04, 305, and 306, and it is confirmed that there is no abnormality by returning to the own NCP. Same <, NCP
13 also sends out a small loop check signal 307, but it does not return.

Through the above process, NCPs 22 and 13 detect an abnormality on the small loop and form a detour 42.53, and from then on,
The message is sent to this detour 42.53. Also, NC
P22.13 periodically issues a small loop check signal and a large loop check signal to check whether the fault has been recovered. The large loop check signal is transmitted without being detoured to all NCPKs,
This is to check that you have recovered.

By performing such an abnormality processing operation K, messages are transmitted in a loop passing through the detour paths 42 and 53 until the failure A is recovered.

FIG. 5 is an explanatory diagram of the message transmission path during a failure in the loop transmission system of FIG. do. Due to the above abnormal processing operation, the detour 42.53 is formed, so the message is N CP 21.22.12.11 after the detour is formed.
．． 16.15.1! .

13. It is transmitted through the routes 23, 24, 25, 26, and 21.

The message 402 that has traveled through the transmission system along the path indicated by the thick line and returned to the NCP 21C is erased after being verified as a self-originated message.

In this way, in the loop transmission system to which the present invention is applied, each N
The CP verifies the SA part of the received JTS message,
Determine whether the message is self-sent,
As a result, if the message is an original call, the message is deleted without being relayed. Therefore, in such a loop transmission system, if there are multiple NCPs with the same address in the transmission system, the message is not transmitted to all NCPs in the transmission system and is deleted midway.

Figure 6 shows NCPs with the same address in the loop transmission system.
0 is an explanatory diagram of the operation in the case where a plurality of . At this time, NCP21 sends message 40
3, it goes through loop 2ONCP22 and goes to NCP
Reach 23. As a result of the message 403 being verified by the NCP 23, the address N is confirmed and the message is deemed to be a self-sent message and is deleted.
Not relayed to CP 24.25.26.

FIG. 7 is an explanatory diagram of the operation of address duplication check according to the present invention.

The address duplication check performed by the present invention is performed at the start-up of each NCP, that is, when a new NOP is installed due to expansion, and when the formed detour is released, that is, after a failure is recovered and repaired. K is executed when the NCP or transmission line is reinserted into the loop.

First, the reason why the address duplication check is executed when detouring is canceled will be explained.

In FIG. 7, it is assumed that as a result of failures in the transmission path at two locations, an isolated portion A within the transmission system surrounded by a chain line is generated. N CP 2 with a new address N1 in this rising part A
When rs rises, an address duplication check is performed, but this check is limited to only within isolated portion A. In reality, the address of NCP21 is also N, and even though there are multiple NCPs with the same address in the loop transmission system, the check is in isolated part A, so N
C]) Address overlap phase of 21.23 is not detected. Therefore, even when excluding the detour N, it is necessary to double check that the address is <N5.

Since a new address is assigned when each NCP is started up, it is of course necessary to check for address duplication.

Next, the actual address duplication check operation by each NCP will be explained.

FIG. 8 is an explanatory diagram of the address train relay operation, and FIG. 9 is a W6 diagram of the final address train data section in FIG.

Each NCP sends out an address train as a message for checking address duplication when it starts up and when it cancels the detour it has formed. Specifically, this 'r address train has a function code indicating that it is an address train in the FC part of the message, and has its own address in the data part (Data). Sequentially, the addresses of NCI) are added to the data section. That is, each NCP that receives this message adds its own NCP address to the end of the data section and sends it out next. In FIG. 8, when the address train is sent to loop 2 from NCP 21 of the start-up poem, NCP 22, 23, 24, .
25 to add their own addresses, NC
In P26, the addresses of the data section are in columns N1 to N60. As shown by the arrow in FIG. 8, after making two rounds within the transmission system, the address train is erased from the source NCPK. Specifically, an NCP that has the same address as the SA part in the message has the same address as 31M4 in the data part.
When extracted, the two rounds and lAJ+, 4r Shitemen-
1! - Erase the page.

N2 to N6 not indicated by 1010 in FIG. 9 are the addresses of each NCP added to one round, and N2 to N6 indicated by 1011
N6 adds 1 piece to 2j4'e 7' 7C6N CP
No t' tress. Source NCP21 is Koshin 1
Since the address is added three times at the end of IJ24 and at the end of the second round, at that point, the own address N1 of 3 leaps is produced and this message is erased.

Next, the processing of each fSCP when receiving 1 address... rain will be explained.

FIG. 10 is an explanatory drawing of the data area in each NCP for the 11th Hiiragi check showing an accurate example of the present invention.
The figure shows address train reception f! In the processing flowchart of each NCP at the time, i is executed.

In FIG. 11, the NCP that receives the address train first adds its own address to the data section (block 901). Next, the resentment detection 7 lag area 801 and the abnormality detection flag area δ02 shown in FIG.
to “OI+” (block 902). Next,
Receive t: The SA part of the data and the own address match, it is self-originated data, and there are 3 own addresses in the NCP address string of the data part (i; If there are 4 or more, the data within the transmission system is Look at the address train that has gone around twice and use its data section to check the address ff1lf (
Block 903°90 Cow, 905). As a result, if all duplicates are detected (duplicate detection flag -1''), it sends data indicating address 1z duplicate detection to the host processing device, puts itself into through mode, and stops sending self-transmitted data. This enables normal transmission in the entire transmission system (blocks 907, 90ε(, 917)).

If the received data is not self-transmitted data, the counter 803 first counts how many source NCP addresses of the SA section are present in the NCP address string of the data section, and then counts how many times the message has been sent. (blocks 903 and 911). That is, when there are more than one source NCP in the data section, the message is the same as the one in the transmission system. Then, the number of own addresses existing in the NCP address string of the data section is counted by the counter 80.
If it is not 3 or less, the error detection flag area 802 is set to ``1'' to indicate that the own address is enabled or present, and the received message is processed depending on whether or not it is currently being detoured according to the own NCP state. It is sent to the loop transmission path and the detour Ijl path (blocks 912 to 916).

Even when there are only two or fewer local addresses in the data field for local or self-transmitted data, the received message is similarly sent out according to the local NCP status (block 904,
914, 915, 916).

Finally, check the abnormality detection flag area 802, and if "1" is set there, it will check whether or not its own address is duplicated. Send train (block 909)
．． 910).

Next, the processing of Atonenos duplication check (block 905) in the flowchart of B 111 to 4 will be explained with reference to FIGS. 12, 13, and 14.

No. 121a is a diagram showing loop 2 of every two loops of loop transmission.

Now, there are two NCPs with the same address N□ in the transmission system.
It is assumed that there are NCPs 21 and 24 having address N1. At this time, when the NCP 21 sends out the address train 4a3, it is erased by the NCP after going around the transmission system once instead of twice because of the duplication of the address train 403 ni and the address N□. In this case, the data portion of the address train finally received by the NCP 21 has the contents shown in FIG. If this address string is normal, the portion 1020.1021 between the own address N1 in the address string is the same.
- content (1010.1011 in Figure 0)
reference).

However, since NCP21.24 has the same address N□, the 1.1020;1021Q-addresses do not match. In other words, by determining whether or not the part surrounded by the own address in the data part of the self-originated address train matches, it is determined whether or not there is an NCP with the same address as the own NC'P in the transmission system. You can check whether

FIG. 14 is a detailed process 712-chart of address duplication check showing an embodiment of the present invention.

First, it is detected which IK position the 1's own address is located in the NCP address string of the data section (block 90δO).
). Here, set the first own address to 1 in the NCP7 address column.
It is assumed that the second self-address is located at the first and the third self-address is located at the first. At this time, the second to (1-1)th and (L+1)th to (
j−1)th NCP addresses are compared in order (blocks 9061 to 906δ), and if a mismatch is detected, “1” is set in the duplicate detection flag area 801 (
Block 9056) ends this checking process. For example, if the own address position in the data section is N
1, the own address position is the 12th, 7th (1), and 13th (mu).

Therefore, first let k be 1, and (k+1)th and (1+
k) Compare the th address, ie the 2nd and 8th addresses (blocks 9051.9052). In Figure 9, the second and eighth addresses are both N2, so it is determined that they match, and then Kkk2 is set and ≧1.
−2, that is, determine whether the number of comparisons has ended,
If the process has not yet finished, the process returns to block 9062 (blocks 9053 to 9055). When k-2, (k+1)
th and (10k)th addresses, i.e. 3rd and 9th
When the th addresses are compared, both are N, so it is determined that they match (blocks 9052 to 9053). In this manner, the comparison operation is repeated as long as there is a match.

If even one of the comparison results does not match, it is determined that there is an abnormality, and the duplication detection flag 801K "1"' is set (block 9056).

In this way, each NCP sends an address train when starting up itself and when canceling a detour, so that the NCP that has the same address as its own NCP in the transmission system
It is possible to check whether P exists or not.

In the embodiment, since an address train that makes two rounds within the transmission system is used, the source NCP can only detect the existence of one NCP having the same address as itself. However, by using an address train K that makes n rounds in the transmission system, the presence of up to (n-1) address duplication NCPs can be detected using the same method as in this embodiment.

〔Effect of the invention〕

As explained above, according to the present invention, if an address is set in advance for each NCP in a loop transmission system, it is possible to detect duplication of NCP addresses, so that messages may be routed within the transmission system due to address duplication. It is possible to prevent the message from being erased before it has completed one cycle, and to ensure normal message transmission.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram of a loop transmission system to which the present invention is applied, Fig. 2 is a diagram showing a message arrangement transmitted in the loop transmission system of Fig. 1, and Fig. 3 is a diagram of a loop to which the present invention is applied. Fig. 4 is an explanatory diagram of the operation when there is no abnormality in the transmission system, Fig. 4 is an explanatory diagram of the operation when a failure occurs in the loop transmission system to which the present invention is applied, and Fig. 5 is an explanatory diagram of the operation when a failure occurs in the loop transmission system of Fig. 4. 6 is an explanatory diagram of the message transmission path in the loop transmission system. FIG. 6 is an explanatory diagram of the operation when a plurality of NCPs with the same address exist in the loop transmission system. FIG. FIG. 8 is an explanatory diagram of the address train relay operation, FIG. 9 is an explanatory diagram of the data part of the final address train in FIG. 8, and FIG. 10 is an illustration of each NCP for duplication check showing an embodiment of the present invention. Figure 11 is an explanatory diagram of the internal data area, and each NCP when receiving an address train.
Processing 7g-chart, Figure 12 shows 2M of loop transmission system.
FIG. 13 is a diagram showing the data part of the address train finally received in FIG. 12; FIG. 14 is a detail of address duplication check illustrating an embodiment of the invention. It is a processing french yard. 1.2: Loop transmission line, 11-26: Transmission control device gl (
NCP), 31-34 = host processing device, 41-44
, 51-54: 1ii1i'! , 801: Mm inspection'M7 easy area, 802: Abnormality detection flag area, 803: Source NCPi counter area. Patent Applicant Hitachi, Ltd. Agent Patent Attorney Masafu Isomura' Figure 1 Figure 3 Figure Cow Figure 5 Figure 7 Figure 12 Figure 13 Figure 1020 1021 Figure 14

Claims (1)

[Claims] (G) In a loop transmission system, an address is assigned to each transmission control device in advance, a detour is formed in the event of a failure, and messages that have gone around the loop transmission path are erased by the transmission control device that sent them. , each transmission control device sends an address train message when starting up itself or canceling a detour, and each transmission control device that receives the address train message sequentially adds its own address to the transmission path. An address check for a loop transmission system, characterized in that, at the same time as sending a message, the transmission control device of the sender analyzes the address string in the message and checks whether there is a transmission control device having the same address as itself. method. ■Special YF characterized in that when the transmission control device of the transmission source detects address duplication, it stops sending out its own transmission data and sends data indicating address duplication to the connected host processing device. An address check method for a loop transmission system according to claim 1. (2) When the source transmission control device detects its own address a predetermined number of times in the address string of the address train message,
The patent claim is characterized in that address duplication is detected by stopping the transmission of the train message and comparing and checking whether or not all addresses in the part of the address string surrounded by the own address match. An address check method for a loop transmission system as described in the first or second range.