JPH03179951A - Polling communication system - Google Patents

Abstract

PURPOSE:To guarantee the delay of transmission of an emergency telegram within a certain upper limit value by dividing all the terminals which perform polling into several groups, accumulating a time required for communication between a center device and the terminal at every group, and performing preferential polling to receive the emergency telegram for one cycle when the value of accumulation exceeds a prescribed value. CONSTITUTION:All terminals 1-16 are divided into a first terminal group of the terminal 1 to the terminal 8, and a second terminal group of the terminal 9 to the terminal 16, and the center device 21 performs the polling and selecting at every group, and accumulates the time required for the communication, and performs the preferential polling to receive the emergency telegram from the terminals 1-16 for one cycle from the next terminals 1-16 when the time exceeds a prescribed upper limit value, e.g. 300ms, at every group, and after that, it continues ordinary polling and selecting. In such a way, the reception of plural telegrams can be performed for one time of polling as guaranteeing the delay of the reception of the emergency telegram within 1.1 seconds even when information is concentrated on the certain terminal in the terminals 1-16, and the communication can be completed in a short time.

Description

[Detailed description of the invention] For industrial use yi.

J presented herein relates to a polling communication method performed by a center device on a communication path to which a plurality of terminals with communication functions are connected.

Conventional technology In the conventional polling communication method, when sending and receiving messages between the center device and each terminal, restrictions are placed on the length of the message, such as a fixed length or a variable length within an upper limit. (-1, and 1 is 1 for each terminal for all terminals)
By setting a value that allows us to predict the time it takes for one polling cycle to complete one polling cycle, we were able to predict and ensure serviceability (polling interval time) for terminals.

The problem that the invention is intended to solve is that when a certain terminal issues information that should not be sent or information that needs to be received, the conventional polling communication method has limitations on message length as mentioned in the previous section. There was a problem in that a telegram of a limited length was sent and received at the polling cycle, and it took a long time to complete sending and receiving all the information.

-1. In order to solve the above problem, if it is possible to send and receive multiple messages using 1-concave polling or serekudink,
In the worst case, the time required for one cycle of polling becomes large &j, and the polling interval time of each terminal becomes large. Therefore, even if a certain terminal generates urgent information,
Issue 21: The problem is that it is not possible to keep track of this information being transmitted in a sufficiently short period of time.

The present invention solves the above-mentioned problems, and provides a polling method that allows handling of multiple messages with one polling or cell/clip ink while also suppressing the delay in transmitting emergency information within a certain upper limit. 1.1 The purpose is to provide a communication power formula.

The polling communication method described in "To solve problem 1", "To solve problem 1, to complete 1", connects multiple terminals with biased communication functions and the center device to the same communication channel, and connects the center device to the center device. This is a communication method that performs polling and selecting to perform communication between the center device and the terminal, and has one concave polling J5,
1 and serekudenink, l2 is said center device and -
- Allow multiple messages to be sent and received between the right terminals, divide all the terminals into several groups in the center device, accumulate the time required for polling and selecting for each group, When this time exceeds a predetermined value for each group, priority polling to receive emergency messages from terminals is performed on all terminals - cycle < i, then normal polling and select deinking are continued. That is.

According to the method described in Operation-1-, all the terminals are divided into several groups &-) The time is accumulated while performing polling and selection for each group, and if the accumulated time is within the predetermined value for each group, , polling and select deinking are performed one after another for each group, and even if an emergency message occurs, it is processed during this polling and one polling for all terminals is completed within the upper limit of the polling cycle. Send(?rsa)'(Uru.

Next 6. 2. If the cumulative time of polling and selecting exceeds a certain predetermined value for each group when the communication end point of a certain terminal in a certain group is 0, priority-1-chi link is performed from the next terminal for the number of cycles. If an emergency telegram is sent <l L, the telegram is received within the L limit of the boring period. Regardless of whether an emergency message occurs or not,
When one cycle of priority polling is completed, normal polling and selecting continue. Therefore, while ensuring that emergency messages are received within the upper limit of the boring cycle, even if a certain terminal is full of information, receiving multiple messages in one poll can be done relatively quickly. It is processed.

Embodiments Hereinafter, embodiments of "JJ" will be described based on the drawings.

FIG. 11 is a block diagram of a communication stage for carrying out the NJ-link communication system of the present invention.

The center device 21 has 16 terminals 1 equipped with communication functions.
・～, 16 are connected to the same communication IAM4't 22, and communicate sequentially by polling, 1: and select deinking.

In this polling selection, the center device as shown in Figure 2! / 21 data requests - Allow the terminal to send data up to a maximum of N consecutively, and after this terminal's sending server completes - f, the center device 21 continues to send data up to a maximum of M. It allows sending to the terminal. The communication with this terminal is terminated by the transmission completion notification from the center device 21, and the center device 21 moves on to communication with the next terminal.

In addition, all the terminals 1 to 16 are classified into a first terminal group from terminal 1 to terminal 8 and a second terminal group from terminal 9 to terminal 16, and the center device 21 performs polling for each group. L selection is performed, the time required for this communication is accumulated, and when this time exceeds a predetermined 1-limit value for each group, for example 300+a seconds, an emergency message from terminal 1-16 is sent. Priority polling for reception is performed for one cycle from the next terminal 1 to 16, and then normal polling and select deinking are continued.

The communication method No. 1 will be explained in detail with reference to the 111th cumulative time chart of the 31st system.

Center-g 73' 21 or t) Once for all terminals 1 to 16 [In communication f for the first terminal group of hE, there is no data to be sent or received between terminal 1 and terminal 6. , the time required for communication between each terminal is 5113
1130Ins in total, and 110+ns and 150Ins between terminal 7 and terminal 8, respectively.
If required, the total time is 290 + ns, and the priority polling is 1 for each terminal group since it is within the upper limit of 30011S for 3 + 11 communications 31 hours given to each terminal group.
I won't get hurt. Priority polling is not performed in the communication to the second terminal group of 14th[1 as well, since the total communication time is 51290IllS for a total of 31 hours.

Next, if the communication from the center device 21 to the first terminal group of ``l'' requires 1501 eS and 140113 eS between terminal 1 and terminal 2, respectively, the cumulative communication time is 290 ns at this point. Yes, and since the limit 11a is not exceeded, the communication moves to the next terminal 3.Assuming that the center device 21 requires the upper limit of communication times for each terminal, 150113 times, for communication with this terminal 3. , through f irises i71' Il, +1 interval number, i: 4
/lo...S, and the cumulative communication time is 1st period 300113
In order to exceed this, priority polling starts from the next terminal d. From terminal 4 to terminal 5, if there is no emergency message,
In total, it takes 11,101 seconds. Assuming that an emergency message has occurred on terminal 6 immediately after the 10th communication ends, in this case, 26 On+s remain in the 1st terminal group of the 1st I-1 communication, and the 11th+iJ ri communication A total of 29011S in the second group of terminals, the first of the second communication
71450+ms total 1000
+ After Todoroki S, an emergency message will be sent.

In the following case, in the configuration of the communication equipment shown in FIG.
This is a near-evil case, but even in this case, the polling interval of terminal 6 is 1 second, and with this method, the polling interval (upper limit of the polling cycle) of each terminal can be kept to about 1.1 seconds. .

In this way, while guaranteeing that the delay in receiving an emergency message is 1.1 seconds, even if information is concentrated on a certain terminal 1-16, it is possible to receive multiple messages by linking 11111; You can complete the ``+'' in a short amount of time.

Because of the effect of [-1] in the present invention, all the terminals that perform polling are divided into several groupsc′j, and in particular, the communication between the center device and the terminals is When this value exceeds a predetermined value, one cycle of priority polling is performed to receive emergency messages, and multiple numbers of messages are allowed to be sent and received in communication between the center device and terminals. ,−
While making it possible to send and receive information using RFTL for a short period of time in response to frequent occurrences of information, it is possible to guarantee that the reception of the transmission f1; in line with emergency messages is within a certain 10 limit value. .

[Brief explanation of drawings]

FIG. 1 is a block diagram of communication equipment that performs the polling communication method of the present invention, FIG. 2 is a normal communication protocol between the center device and terminals in FIG. 1, and FIG. 3 is a diagram of the center in FIG. 1. FIG. 4 is a cumulative time diagram during communication between the device and the terminal. 1 to 16...terminal, 21...center device, 22.
...Communication channel.

Claims (1)

[Claims] 1. A communication method in which multiple terminals with communication functions and the center device are connected to the same communication path, and communication is performed between the center device and the terminals by polling and selecting performed by the center device. Allowing multiple messages to be sent and received between the center device and one terminal by polling and selecting, dividing all the terminals into several groups in the center device, and performing polling and selecting for each group. When the time required for A polling communication method that continues polling.