JPS63114498A - Data collection system - Google Patents

Abstract

PURPOSE:To efficiency improve data collection by branch transmitting a received data signal from a slave station to a prescribed slave station in a master station, detecting the disconnection of the carrier of the transmission signal of the master station in the slave station and controlling the timing of a data transmission to the master station, in a 1 to N polling system. CONSTITUTION:A carrier signal is transmitted from a carrier transmission part 101 to a first data collection slave station 110 by the connecting means 105 of the master station 11, the received slave station 110 detects the disconnection of the carrier signal by a data transmission control means 113 and transmits the data to the master station 100. In the master station 100, this data signal is fetched to a data receiving part 103 and transmitted directly to the next data collection slave station 120, and then the received slave station 120 detects the disconnection of the carrier signal with the completion of the data transmission of the slave station 110 and transmits the data to the master station 100. In such a way, the master station freely sets the slave stations 110-140, the master station monitors the data signal of the previously data collecting slave station and transmits the data in time division to the master station 100, so that the data collection efficiency can be improved.

Description

[Detailed Description of the Invention] [Summary] In a data collection method based on the 1-to-N polling method, a master station branches and sends a received data signal from a slave station to a predetermined slave station, and the slave station transmits the received data signal from the slave station to the parent station. The timing of data transmission to the master station is controlled by detecting a carrier disconnection in the transmission signal of the station, and the slave stations that the master station has designated for data collection sequentially monitor the carrier signal and transmit the data to the master station. By controlling time-division transmission of data, data collection efficiency can be increased.

[Industrial application field]

TECHNICAL FIELD The present invention relates to data collection methods used in telemeters and other applications. In particular, the present invention relates to a data collection method that can improve data collection efficiency in the 1:N polling method.

[Conventional technology]

FIGS. 4 and 5 are diagrams showing the configuration of a conventional data collection method.

The configuration shown in FIG. 4 is an example of a data collection system using a 1:N polling method using star coupling. This method is mainly used to collect data in dispersed and remote areas.

The master station 411 and the plurality of slave stations 421 to 424 are connected to the star-shaped parallel line 45 via modems 431 and 441 to 444, respectively.
1 to 454. The master station 411 sends a polling signal to a plurality of slave stations 421 to 424, and each time one polled slave station responds to the polling signal. That is, polling processing is necessary every time data is collected from one slave station.

The configuration shown in FIG. 5 is an example of a polling type data collection system using a multi-drop line with loop coupling. This method is mainly used to collect data in relatively small areas such as campuses.

The master station 511 and the plurality of slave stations 521 to 524 are connected by a multidrop line 550 via nodes 531 and 541 to 544, respectively. The master station 511 sends a polling signal to the slave station 521, and the slave station 521 adds its own data to the end of the polling signal and sends it to the next slave station 522. Thereafter, in the same way, own station data is sequentially added, and finally all slave station data combined into one message is sent back to the master station 511.

In such a data collection method, it is difficult to collect data only from an arbitrary slave station (group).

[Problem that the invention seeks to solve]

However, the former conventional method has the drawback that polling is required each time data is collected from each slave station, resulting in a decrease in collection efficiency.

The latter conventional method had the disadvantage that all slave stations responded after - times of polling, resulting in a long data message, and the capacity of the master station had to be increased according to the number of slave stations to be accommodated. . Furthermore, since a multi-drop line is used, if part of the line is disconnected, there is a problem in that it has a large impact on the entire system, such as making data collection impossible.

The present invention solves these conventional problems,
It is an object of the present invention to provide a data collection method that can improve data collection efficiency compared to any conventional method.

[Means for solving problems]

FIG. 1 is a block diagram of the principle of the present invention.

In the figure, the connecting means 105 of the master station 100 sends the carrier signal from the carrier sending unit 101 to the first data collecting slave station, and transmits the data signal from the current data collecting slave station to the subsequent data collecting slave stations. The data is output to the data receiving section 103 and branched to the next data collection slave station.

Data transmission control means 1 for each slave station 110, 120, 130
13, 123, and 133 control data transmitting units 111, 121, and 131 that detect disconnection of the carrier signal from the master station 100 and transmit own station data.

[For production]

In the present invention, a carrier signal is sent from a carrier sending unit 101 to the first data collecting slave station by a connecting means 105 of a master station 100, and the slave station that has received the carrier signal disconnects the carrier signal by a data transmission control means. Detected and master station 1
Send data to 00. In the master station 100, this data signal is taken into the data receiving section 103, and the data signal is sent as is to the next data collection slave station.

The slave station that received the data signal detects that the carrier signal is cut off when the data transmission of the previous data collecting slave station ends, and transmits the data to the master station 100.

In this way, in the master station 100, a data collection slave station can be freely set using the connection circuit 105, and the slave station monitors the data signal (carrier signal) of the slave station from which data was collected before.
By time-sharing data transmission to 00,
Data collection efficiency can be increased.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows the configuration of an embodiment of the present invention.

(2) Correspondence between the embodiment and FIG. 1 Here, the correspondence between the embodiment of the present invention and FIG. 1 will be shown.

The master station 100 is assumed to be a master station 200.

Slave stations 110, 120, and 130 are slave stations 310.320.3
3'0.340.

Lines 151-153 are assumed to be lines 401-404.

The carrier sending unit 101 corresponds to the carrier sending circuit 201.

Data receiving section 103 corresponds to demodulation circuit 203 and data receiving circuit 205.

The connection means 105 corresponds to the control circuit 207 and the changeover switches 210 to 214.

The data transmitting units 111, 121, and 131 include data transmitting circuits 315, 325, 335, and 345 and a modulation circuit 31.
It corresponds to 6,326,336.346.

Data transmission control means 113, 123, 133 correspond to demodulation circuits 313, 323, 333, 343 and carrier disconnection detection circuits 314, 324, 334, 344, respectively.

Examples of the present invention will be described below, assuming that the above-mentioned correspondence exists.

In FIG. 2, a master station 200 and slave stations 310, 320.3
30 and 340 are connected via lines 401 to 404.

The output of the carrier sending circuit 201 of the master station 200 is connected to a changeover switch 210, and each output thereof is connected to lines 401-404 via transmission amplifiers 221-224, respectively. Receiving amplifier 2 connected to each line 401 to 404
Each output of 31 to 234 is connected to each selector switch 211 to 21.
4 and the demodulation circuit 2 via receiving amplifiers 235 to 238.
Connected to 03. Each output of each changeover switch 211 to 214 is connected to transmission amplifiers 221 to 214 and line termination circuit 217, respectively. The output of demodulation circuit 203 is connected to data reception circuit 205. The control circuit 207 includes
A carrier sending circuit 201, a data receiving circuit 205, and each changeover switch 210 to 214 are connected.

In the slave station 310, the reception amplifier 3 connected to the line 401
11 is connected to a demodulation circuit 313. Demodulation circuit 3
13 is connected to a carrier disconnection detection circuit 314, and its output is input to a data transmission circuit 315. The output of data transmission circuit 315 is sent to line 401 via modulation circuit 316 and transmission amplifier 318.

In other slave stations 320, 330, 340, receiving amplifiers 321, 331, 341, demodulation circuits 323, 333,
343, carrier disconnection detection circuit 324.334,344,
Data transmission circuits 325, 335, 345, modulation circuit 32
6,336,346, transmission amplifier 328,338.34
Each connection of 8 is similar to the slave station 310.

■, Operation of the example FIG. 3 is a sequence diagram illustrating the present invention in detail.

The operation of the present invention will be described below with reference to FIGS. 2 and 3.

In this embodiment, data is collected in the order of slave stations 310, 320, 330, and 340. In other words, the changeover switches 210 to 214 are configured so that the input signals are connected to the transmission amplifier 2.
21 to 224 and the line termination circuit 217 are set in advance by the control circuit 207 so as to be connected in this order.

When the master station 200 needs to collect data, it transmits the carrier signal sent from the carrier sending circuit 201 to the slave station 310 via the changeover switch 210, the transmission amplifier 221, and the concave line 401.

A carrier signal is a carrier wave used when transmitting data on a line. The carrier signal is sent to the receiving amplifier 3 of the slave station 310.
11 to the demodulation circuit 313, and further input to the carrier disconnection detection circuit 314. The carrier disconnection detection circuit 314 detects the carrier signal and monitors a change point at which the carrier signal becomes disconnected. When it is detected that the carrier signal is disconnected, a control signal is sent to the data transmission circuit 315, and data transmission permission is granted.

The data transmission circuit 315 modulates the data signal with the modulation circuit 316 at the input timing of this control signal, and further transmits it to the master station 200 via the transmission amplifier 318 and the line 401.

The modulated data signal is transmitted to the master station 200, and
00 is input to the demodulation circuit 203 and the data reception circuit 205 for reception processing. At the same time, this data signal is branched to the selector switch 211 side.

The data signal from the slave station 310 switched by the changeover switch 211 is sent to the slave station 320 via the transmission amplifier 222 and the circuit 91320.

Here, the data of the data signal sent to the slave station 320 is ignored by the slave station 320, and only its carrier signal is monitored.

Similarly, data signals from slave stations 320, 330, and 340 are received by demodulation circuit 203 and data receiving circuit 205 of master station 200, and are sent back to the next slave station. The changeover switch 214 connects the data signal sent from the slave station 340 to the line termination circuit 217.

In this way, by setting the changeover switches 210 to 214 in advance by the control circuit 207 of the master station 200 to connect only the slave stations from which data is to be collected, and by sending a carrier signal to the first slave station, the slave stations can transfer carrier signals to each other. It is possible to monitor signals and transmit data to the master station 200 in a time-sharing manner. The master station 200 processes the data sent in a time-division manner based on the control data set by the changeover switches 210 to 214, thereby making it possible to collect data from a desired slave station.

Therefore, for slave stations that do not require data collection,
The bus can be set arbitrarily by setting the switching switches 210 to 214 on the master station 200 side.

Further, if a transmission error is found in the data received and processed by the data receiving circuit 205, re-collection control can be easily performed by operating the changeover switches 211 to 214 under the control of the control circuit 207. For example, when operating according to the data collection order described above,
If a transmission error is found in the data collected from the slave station 310, the output setting of the changeover switch 214 is controlled so that the data signal is sent to the slave station 310 again at the time when data from the slave station 340 is collected. This allows for re-collection.

At this time, the output of the changeover switch 211 is set to be connected to the line termination circuit 217 at the same time. Alternatively, after data collection is completed, press the selector switch 21 again.
0 may be set on the slave station 310 side, and the changeover switch 211 may be set to be connected to the line termination circuit 217.

Further, in the embodiment described above, by setting the output of the changeover switch 214 to be connected to the transmission amplifier 221, unlimited cyclic data collection can be performed.

■.Summary of Examples As explained above, the present invention utilizes the on/off of carrier signals as polling control, and the slave station monitors the carrier signal to sequentially transmit data signals to the master station in a time-sharing manner. be able to.

Further, data collection efficiency can be improved by returning data signals transmitted from a slave station as they are to a predetermined slave station at the master station.

■, I] Form Takanami Note that in the embodiment of the present invention described above, an example is shown in which the number of slave stations is four, but the master station has a changeover switch corresponding to the number of slave stations. By configuring this, the number of slave stations that can be accommodated can be easily increased.

In addition, we have explained a method in which the slave station detects the interruption of the carrier signal and controls its own data transmission, but the master station also has a method for adding a specific signal (a signal indicating the end of data transmission) to the end of the data signal. A carrier sending circuit (added when cutting off a carrier signal) and a data transmitting circuit of a slave station may be provided, and each slave station may detect this specific signal and control the timing of data transmission.

Note that if the line is an analog line such as a telephone line, it is preferable to control data transmission by detecting disconnection of a carrier signal in addition to this specific signal in order to improve reliability.

Furthermore, in "1. Correspondence between Examples and FIG. 1",
Although the correspondence between FIG. 1 and the present invention has been described, those skilled in the art will easily imagine that the present invention is not limited to this and that there are various modifications.

〔Effect of the invention〕

As described above, according to the present invention, the master station sends the data signal from the slave station as it is to the next data collecting slave station, and the slave station controls the transmission timing of the data signal by disconnection of the carrier signal. , data transmission is performed immediately after the data transmission of the previous slave station is completed, and the master station can collect data in a time-sharing manner, which has the effect of increasing data collection efficiency.

In addition, the master station can easily and variably set the order or identification of data collection slave stations, and can also easily perform cyclic data collection and re-collection for slave stations where transmission errors have occurred. It is extremely useful in practical terms.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the principle of the present invention, Fig. 2 is a block diagram of the configuration of a data collection method according to an embodiment of the present invention, Fig. 3 is a sequence diagram explaining the present invention in detail, and Fig. 4 is a conventional block diagram. A diagram showing a data collection method. FIG. 5 is a diagram showing a conventional data collection method. In the figure, 100.200 is the master station, 110.120, 130, 310, 320, 330.3
40 is a slave station, 101 is a carrier sending section, 103 is a data receiving section, 105 is a connecting means, 111, 121, 131 is a data transmitting section, 113.'1
23, 133 is data transmission control means, 151 to 153,
401 to 404 are lines, 201 is a carrier transmission circuit, 203 is a demodulation circuit, 205 is a data reception circuit, 207 is a control circuit, 210 to 214 are changeover switches, 217 is a line termination circuit, 221 to 224.3LL 321, 331 , 341 are transmitting amplifiers, 231 to 238, 318, 328, 338, 348 are receiving amplifiers, 313, 323, 333, 343 are demodulating circuits, 314.
324, 334, and 344 are carrier disconnection detection circuits; 315, 325, 335, and 345 are data transmission circuits; and 316, 326, 336, and 346 are modulation circuits. 771 Shikoki Akebono S ■ 1 masterpiece) - Punmata 1 Figure 3

Claims (1)

[Claims] A master station (100) and a plurality of slave stations (110, 120, 120,
130), in which data is collected by polling from a master station (100), the master station (100) transmits a carrier signal from a carrier transmitter (101) to the first data collecting slave station. For subsequent data collection slave stations, it includes connection means (105) for outputting the data signal from the current data collection slave station to the data receiving section (103) and for branching and sending the data signal to the next data collection slave station. , Each slave station (110, 120, 130) is a master station (100)
data transmission control means (113, 123, 133) that controls a data transmission section (111, 121, 131) that detects a disconnection of the carrier signal from the carrier signal and transmits own station data;
).