JPH06104907A - Polling system - Google Patents

Abstract

PURPOSE:To shorten the collection time of telemeter data by adding state information of each slave station and a succeeding station number to transmission data sent by a slave station and allowing the slave station itself to discriminate the transmission sequence and to send data in the polling system of a telemeter system where plural slave stations are connected to the same line with the master station and they send/receive data. CONSTITUTION:Each of slave stations (A) 9-1 to (N) 9-N is provided with a station state storage section 2 storing station state information included in received data, a succeeding transmission station discrimination section 4 of each slave station discriminates a succeeding transmission station based on the station state information of all slave stations stored in the section 2 and adds a succeeding transmission station number to transmission data. The transmission station discrimination section 3 of the slave station discriminates the transmission station from the added succeeding transmission station number and a relevant slave station sends telemeter data. Thus, a data transmission request from the master station is not required except at system start and data interruption from a slave station and the rate of using the line of transmission of telemeter data is increased and the data collection time is shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a polling system,
In particular, the present invention relates to a polling method of a telemeter system in which a plurality of slave stations exchange data with a master station connected to the same line.

[0002]

2. Description of the Related Art Conventionally, in this type of polling system, a master station device sequentially requests data transmission with the station number of the slave station, and the slave station adds the station number to the telemeter data and transmits it. Was there.

[0003]

In this conventional polling method, since the master station device makes a data transmission request to the slave station, it is necessary to transmit the transmission request from the master station device for the number of slave stations. However, there is a drawback that the line utilization rate for transmitting telemeter data is reduced.

An object of the present invention is to eliminate the above-mentioned drawbacks, eliminate the need to send a transmission request from the master station device in correspondence with the number of slave stations, and provide a polling method in which the line usage efficiency of telemeter data is significantly improved. To do.

[0005]

The system of the present invention is a polling system of a telemeter system in which a plurality of slave stations exchange data with a master station connected to the same line by polling. Station status information including its own station number, slave station status, and next transmission station number is added to the telemeter data as transmission data sent by the station, and each slave station determines the next transmission station based on the status information. The system has a configuration that does not require a transmission start request from the master station to a slave station and a transmission request from the slave station except when data is lost.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a system configuration of a polling system according to an embodiment of the present invention.

In the embodiment shown in FIG. 1, a master station device 8 and n slave stations (A) 9-1 connected to the master station 8 through a line 10.
(N) 9-N is used as an example.

Each slave station has a receiver 1 for receiving telemeter data via the line 10, a station status storage 2 for storing status information of each slave station, and a next transmission station number in the received telemeter data. Transmitting station discriminating unit 3 for discriminating whether or not a station
A next transmitting station discriminating unit 4 for discriminating the next transmitting station by judging from the station state information, telemeter data 5 collected by the own station,
A transmission data editing unit 6 for editing the transmission data by adding the station number of the local station, station status information and the next transmission station to the telemeter data 5, and a transmission unit 7 for transmitting the transmission data edited by the transmission data editing unit 6. It has a configuration provided.

Next, the operation of this embodiment will be described.

The master station device 8 transmits a transmission request with the next transmission station number added when the system is started and when the transmission of data from the slave station is interrupted.

In the slave station, for example, the slave station (A) 9-1, the transmission request received from the master station device 8 is received by the receiving section 1 and the station state storage section 2 is initialized.

The transmitting station discriminating unit 3 compares the next transmitting station number in the transmission request with the own station number, and if they match, the transmission data editing unit 6 adds the own station number and the own station state to the telemeter data 5. Further, the next transmitting station discriminating unit 4 sends the transmission data to which the next transmitting station number, which has been read out from the station state storage unit 2, is added from the transmitting unit 7 to the line 10.

The transmission data sent from the slave station to the line 10 is
Received by all other slave stations. In all the other slave stations, the receiving unit 1 receives the transmission data and stores the added station state information in the station state storage unit 2. Further, the transmitting station discriminating unit 3
Compares the next transmission station number in the transmission data with its own station number, and if they match, the transmission data editing unit 6 causes the telemeter data 5
In addition, the own station number and the own station state, and the next transmitting station number read and judged by the next transmitting station discriminating unit 4 from the station state storing unit 2 are added, and transmitted as transmission data from the transmitting unit 7 to the line 10.

FIG. 2 is a diagram showing an example of a format of a transmission request from the master station and transmission data from the slave station.

The transmission request 13 includes a master station number, a master station state,
It consists of the next transmitting station number.

The transmission data 14 is composed of its own station number, slave station state, telemeter data, and next transmission station number.

FIG. 3 is a time chart of on-line data in the embodiment of FIG. 1, showing transmission of each device to the line.

Since all the devices are connected to one line, only one device can transmit at a time. Reference numeral 13-
Reference numerals 14-1 to 14-1 denote transmission requests from the master station device 8, respectively.
14-N are each slave station devices (A) 9-1 to (N) 9
The transmission data of -N is shown.

When the system is started, the master station device 8 transmits a transmission request (next transmission station number (A)) 13-1.

Upon receiving the transmission request 13-1, each slave station stores the internal master station status therein and determines the next transmitting station as the slave station (B) from the stored station status information.

In response to the next transmission station number (A) of the transmission request 13-1, the slave station (A) 9-1 adds its own station number (A), its own station status, and the next transmission station number (B) to the telemeter data. , The transmission data 14-1 is transmitted.

The other slave stations receive the transmission data 14-1 transmitted by the slave station (A) 9-1, store the internal slave station status, and store the next slave station status information from the stored slave station status information. The transmission station number is determined to be (C). According to the next transmission station number (B) of the transmission data 14-1, the slave station (B) 9-2 adds the self station number (B), the self station state and the next transmission station number (C) to the telemeter data, 14-2 is transmitted.

Similarly, other slave stations are slave stations (B) 9-2.
Of the transmitted transmission data 14-2 is stored, the state of the slave station therein is stored, and the next transmission station number is determined to be (D) from the stored slave station state information.

According to the next transmission station number (C) designated by the transmission data 14-2, the slave station (C) 9-3 includes the self station number (C), the self station state, and the next transmission station number (D) in the telemeter data. In addition, the transmission data 14-3 is transmitted.

Similarly, the transmission data 14-N is transmitted to the final station (N). Here, consider a case where some abnormality occurs in the slave station and data cannot be transmitted.
As an example, assume that no data is transmitted after transmitting the transmission data 14-N. In that case, since the data is not received, the master station device 8 determines that the slave station (A) 9-1 is abnormal, and determines that the next transmission station number is (B) from the stored station state information. The transmission request 13-2 is transmitted. After that, the slave station (B) 9-2 transmits the transmission data 15-1 as in the case of the normal processing.

[0027]

As described above, according to the present invention, the next transmission station number is determined by using the own station number and the slave station state information in the transmission data transmitted by a plurality of slave stations that exchange data by the polling method. , By adding it to the transmission data, the next transmitting station can be discriminated by the slave station, the data transmission request from the master station to the slave station becomes unnecessary, and the line usage rate of telemeter data transmission is reduced. It has a large effect that data can be collected in a shorter time than before.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of a polling system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a format of a transmission request and transmission data in FIG.

FIG. 3 is a time chart for explaining the operation of the polling method shown in FIG.

[Explanation of symbols]

 1 receiving unit 2 station state storage unit 3 transmitting station discriminating unit 4th transmitting station discriminating unit 5 telemeter data 6 transmission data editing unit 7 transmitting unit 8 master station 9-1 to 9-N slave station (A) to slave station (N ) 10 lines 13 transmission request 14 transmission data

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8220-5K H04L 13/00 307 Z

Claims (1)

[Claims] 1. In a polling method of a telemeter system in which a plurality of slave stations exchange data with a master station connected to the same line by polling, telemeter data as transmission data transmitted by the plurality of slave stations. To
Station status information including own station number, slave station status, and next transmission station number is added so that each slave station can determine the next transmission station based on the above status information, and system start from the master station to the slave station. And a polling method that does not require transmission requests from slave stations except when data is lost.