JPS6262645A - Multiple address communication system - Google Patents

Abstract

PURPOSE:To attain surely the decision of effect of multiple address communication by providing a means confirming the order of arrival of a reply reception signal from a slave station to a master station. CONSTITUTION:An arrival order confirming section 18 for a reply signal is provided with an equipment giving a time to an arrival signal, an equipment storing a slave station address schedule arrival order and an equipment collating the address of signal arrived actually. If a part of the reply from the slave station has missing, and it is compared with the reply of slave stations before and after it, and when no missing exists entirely, it is decided that the reply from the station does not reach the master station due to a transmission error. A confirming section 18 informs the name as to the slave station to a reply urging section 17. The urging section 17 forms an urging message and informs it to an address addition section 13. The address addition section 13 forms the name of the said slave station, adds an individual address and sends the urging message to said slave station.

Description

[Detailed Description of the Invention] [Summary] When broadcasting from a master station to multiple slave stations connected in a loop with the master station, if the reception of the response from the slave stations cannot be confirmed, the transmission This is a broadcast communication method in which the master station requests a response only from the slave station that sent the response that caused the error.

[Industrial Field of Application] The present invention relates to a broadcast communication method when broadcast communication is performed from a master station to a plurality of slave stations using communication lines connected in a loop.

[Prior Art] A broadcast communication system using a loop-shaped communication line as shown in FIG. 4 is well known. In FIG. 4, 10 is a loop communication line, 20 is a master station A, 31 to 3n are slave stations B, C,
- indicates. 11 is a data processing section, 12 is a data transmitting section, 13 is an address adding section, 14 is a transmitting section, 15 is a receiving section, 16 is an address checking section, and 17 is a response prompting section. As shown in the time chart shown in Figure 5, time is plotted on the Y axis, and
If the station name is taken as the axis, when there are four slave stations B to E, data is sent from the transmitter 14 only once from the master station A20 to all the slave stations as broadcast communication (multiple times in the drawing). (It looks like this, but it passes through each slave station in sequence from station E to station B). At this time, the address adding section 13 sends out the output from the data transmitting section 12 as a group address (or global address). Each slave station sequentially receives and decodes the signal, and sends a response signal back toward the master station A20.

In the illustrated arrangement, the W responses from the slave stations are first sent from the E station, and lastly the responses from the eight stations 31 are sent out, and they reach the master station in that order. In the master station A20, after receiving it in the receiving section 15, it sends a response to the data processing section 11, and at the same time, the address checking section 16 checks the slave station address in the response signal. Check the slave station that responded.

[Problems to be Solved by the Invention] In FIG. 4, there is no problem when the master station A confirms the response from the slave station, but the address check unit 16 determines that there is a slave station for which the response cannot be confirmed. When it is determined that there is no response, the reason for the lack of response is unknown, so the next process begins. The individual address of the slave station is specified in the response prompting section 17, a response prompting signal is obtained from the data transmitting section 12, the individual address is added by the address adding section 13, and the signal is transmitted from the transmitting section 14. At this time, there are various reasons why the response reception could not be confirmed among the many slave stations. For example, it could not operate due to a power outage, reception could be done but the response sending part was out of order, or the output of the transmission signal was out of order. Therefore, when there are a large number of slave stations connected to a loop line, when a station that has not received a response is prompted to respond, regardless of the reason, the slave stations that are in a stopped state are also urged to respond. As a result, processing efficiency became extremely poor.

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks, and to provide a broadcast communication system in which responses from slave stations are checked and only those slave stations that have sent a response but have caused a transmission error are prompted to respond. It is in.

[Means for Solving the Problems] The means adopted by the present invention to achieve the above-mentioned object is that a master station and a plurality of slave stations are connected in a loop, and the master station performs broadcast communication to the slave stations. In the broadcast communication system, the master station is equipped with means for checking the order in which response reception signals from the slave stations arrive.

[Operation] When checking the addresses of response signals from slave stations at the master station, it can be determined that response signals from slave stations that should have arrived have not arrived by also checking the order in which they arrived. . Broadcast communication data is supposed to be short-circuited for the station whose power is cut off, so the original arrival order is different, and if the station is skipped, it would be useless to urge that station to respond. Therefore, a reminder is sent only to slave stations that can be determined to have experienced an error directly related to the transmission path.

[Embodiment] FIG. 1 is a diagram showing the configuration of an embodiment of the present invention. In FIG. 1, 10 is a loop communication line, and 2o is a master station A331~
3n indicates a slave station. 11 is a data processing section, 12 is a data transmitting section, 13 is an address adding section, 14 is a transmitting section, 15 is a receiving section, 16 is an address checking section, and 17 is a response prompting section. Reference numeral 18 denotes a response signal arrival order confirmation unit, which includes a device for assigning a time to the arrival signal, a device for storing the expected arrival order of slave station addresses, and a device for collating the address of the signal that actually arrived. There is.

When the operations of each slave station are all normal, the responses arrive successively in the order of response (E), response (D), response (C), and response (B).

If a part of the response from the slave station is missing as shown in Figure 2, compare it with the responses from the previous and subsequent slave stations, and if it does not exist at all, the response from that station (in Figure 2, the slave station It is determined that the response from C) did not arrive at the master station due to a transmission error. That is, since the signal has been given a time by the arrival order confirmation unit 18 of the master station 10, the order and time can be confirmed, and the missing slave station can be identified by comparing it with the scheduled arrival order.

Therefore, the confirmation unit 18 notifies the response prompting unit 16 of the name of the slave station. The dunning unit 16 creates a dunning message and notifies it to the address adding unit 13.

The address adding section 13 knows the name of the slave station, adds an individual address, and sends a reminder message to the slave station.

Next, as shown in FIG. 3, when one of the slave stations is powered off, there is no dropout in the arrival of response signals, but the number of signals is reduced. Therefore, the arrival order confirmation unit 18 determines that no response has been issued from the child station (child station D in FIG. 3), that is, there is no child station on the loop. Therefore, the slave station is not prompted to respond.

[Effects of the Invention] In this way, according to the present invention, since the arrival order of slave station response signals is confirmed at the master station, arrival/non-arrival can be determined immediately after broadcast communication is sent, and transmission problems can be improved. It is possible to effectively prompt a slave station with an error to respond. Therefore, the effectiveness of broadcasting and communication can be determined reliably.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, FIGS. 2 and 3 are explanatory diagrams of the operation of FIG. 1, FIG. 4 is a diagram explaining the conventional broadcast communication system, and FIG. FIG. 4 is an explanatory diagram of the operation of FIG. 4; 10-loop communication line 11--data processing section 12--data transmitting section 13-address adding section 14-transmitting section 15...receiving section 16--address checking section 17--response prompting section 18--arrival order 6m Recognition Department 20 - Master Station A 31~3n...Slave Stations B, C-... Patent Applicant Fujitsu Limited Agent Patent Attorney Eisuke Suzuki Figure 1-B

Claims (1)

[Claims] A master station (20) and a plurality of slave stations (31) to (3n) are connected in a loop, and the master station (20) performs broadcast communication to the slave stations (31)... A broadcast communication system characterized in that the master station (20) is equipped with means (18) for checking the order of arrival of response reception signals from the slave stations (31).