JPS6074845A - Telemeter system - Google Patents

Abstract

PURPOSE:To collect satisfactorily the latest data without imparing power saving by transferring the idle data to a master station in case the polling is applied to a busy state, and renewing data after releasing the busy state to transfer the renewed data to the master station. CONSTITUTION:The water level is measured by a sensor 100 of a telemeter system, and the busy state obtained when the polling is applied from each of switches SA-SD is supplied to AND gates 302A-302D of a measurement controller 300. While the output of a switch SE is supplied to the other side of the gates 302A-302D and one side of AND gates 306 and 310 respectively. The outputs fed from gates 302A-302D are supplied to a memory 304, and the idle data is transferred to a master station from a communication device 400. Then the output of an FF is supplied to the gates 306 and 310, and the outputs of gates 310 and 306 are supplied to a timer 312 and the memory 304, respectively. The data of the memory 304 is renewed after the busy state is renewed. Then a relay switch RS is actuated to transfer the latest data to the master station.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical field of the invention The present invention relates to a telemeter system that transfers data measured by each of a plurality of slave stations to a master station. This relates to improvements in data transmission.

(Background of IIO technology There are various types of telemeter systems in Australia, and the data collection intervals in these systems vary depending on the object to be measured.

If the target changes frequently, it is necessary to constantly collect data; however, if the target changes slowly, such as the water level of a river, it is necessary to collect data at appropriate intervals, such as every hour. By collecting data in advance, changes can be fully understood.

By the way, in such a telemeter system, when the master station polls one of the slave stations for data transfer, a state in which the measured data is uncertain, that is, the data to be transferred from the slave station to the master station is not established. Although it is desirable to be able to send the latest measurement data to the master station even if a state where the current measurement data is not present (hereinafter referred to as the "1"+3usy state") occurs, conventional systems cannot meet such requirements. Therefore, there is a demand for the development of technical means that can solve this problem.

(c) Prior Art and Problems FIG. 1 shows an example of an agricultural and water system which is an example of a telemeter system. In this figure, the slave station 10 includes a sensor 12 for water level measurement. A data transmission control device 14 that controls the output of measured data. It has a communication device 16 that communicates with the master station 20 and transfers data, and a power source 18 consisting of a solar cell, a storage battery, or the like. Data measured by the sensor 12 is transferred to the master station 20 by the communication device 16 based on polling from the master station 20 by the data transmission control device 14 .

FIG. 2 shows an example of the configuration of the slave station 10. As shown in FIG. In this figure, the sensor 12 digitizes and outputs the measured data, which is output by the switch SA or S.
It is symbolically represented by D. The switches SA to SC are connected to the memory 32 via NAND gates 30A to 30C, respectively, and the switch SD for outputting a Busy signal is connected to the input of an AND gate 34 connected to the memory 32. Further, a power source 18 is connected to the switches SA to SD via a relay switch R3 and resistors RA to RD, respectively, and the other ends of the switches SA to SD are grounded. The aforementioned N
For other inputs of AND gates 30A to 30C, Bu
It is connected so that the sy signal is input.

The communication device 16 is provided with a modulation device 36, and is configured so that data input from the memory 32 is modulated based on a polling signal transmitted from the master station 20 and transmitted. The polling signal is also input to the relay coil RCL and the AND gate 34.

In the slave station 10 configured as described above, the relay coil R
CL is energized only during polling, and relay switch R3 is turned "ON". Further, in the Busy state, the switch SD becomes rONJ, and the Busy signal becomes the logic value rLJ level.

On the other hand, the memory 32 outputs the NAND gate 30A when the output of the AND gate 34 reaches the rHJ level of the logical value.
Incorporating the output of 30G or water level data,
Update data.

Therefore, first, when the master station 20 is in a state other than Busy,
When polling is applied from , relay coil RCL is energized and relay switch R3 is turned "ON", and
The data in the memory 32 is updated, and the updated data is transferred to the master station 20 by driving the modulation device 36.

Next, when polling occurs in the Busy state,
Although the relay switch R3 is turned ON, since the output of the AND gate 34 is at the rLJ level, the data in the memory 32 remains as it was at the previous polling and is not updated. Therefore, the same data as the previous data will be transferred to the master station.

As described above, in the conventional device, from the viewpoint of power saving, power is supplied only during polling to update the data in the memory 32, so if polling occurs in the Busy state, the data in the memory 32 will be updated. Since data is transferred and is not updated regardless of changes in water level, if a busy state occurs continuously during polling, it will cause a serious problem in data collection.

Object of the Invention The present invention has been made in view of the above points, and an object of the present invention is to provide a telemeter system that can efficiently collect the latest data without sacrificing the advantage of saving power. That is the purpose.

Structure of the Invention In order to achieve this object, the system of the present invention provides communication between the master station and the sensor means that outputs measured data and outputs a signal indicating that when the data is uncertain. and data transmission control means for causing the communication means to transmit control information to the master station if the signal is generated during polling from the master station.

(F) Embodiments of the Invention The present invention will now be described in detail according to embodiments shown in the accompanying drawings.

FIG. 3 shows an embodiment of a slave station in a telemeter system according to the present invention. In this figure, the sensor 100 has the function of measuring the water level, digitizing and outputting the data, as described above. Switches SA to SD symbolically represent functions capable of outputting such digitized data. The switch SE symbolically represents a function capable of outputting a Busy signal representing a Busy state. These switches S
One end of A to SR is equivalent to being grounded, and the other end of switch SA to SE is connected to resistor R.
Connected to relay switch R3 via A to RE,
Relay switch R3 is connected to power supply 200. The data represented by the switches SA to SD is composed of an appropriate number of focus units as necessary. For example, data is represented by a BCD code. Also, Bu
When the sy signal is in the Busy state, the switch SE is
It is a signal that becomes ONJ and becomes a logic low level (the same applies hereafter), and its time is, for example, 100 to 300 mS.

Next, the other end of switch SA or SD is set to NA by two people.
The NAND gates 302A to 302D are connected as inputs to the NAND gates 302A to 302D, respectively.
The other end of the switch SE is connected as the other input. Further, the outputs of the NAND gates 302A to 302D are connected to be input to the memory 304, respectively.

The other end of the switch SR mentioned above is connected as an input to a two-man-powered AND gate 306, and is also connected to the inverter 3.
08 as a two-man AND gate 3100 input. A communication device 400 is connected to the other inputs of the AND gates 306 and 310, and a polling signal from the master station is input thereto. Further, the polling signal is applied to the relay coil RCL. The output of AND gate 306 is connected to memory 304 and modulator 402 . Further, the output of the AND gate 310 is connected to a timer 312, and the output of the timer 312 is connected to the modulation device 402. That is, data in the memory 304 is updated based on the timing of the output of the AND gate 306.

A power supply 200 is connected to the data transmission control device 300 and the communication device 400, and power for operation is supplied thereto. Data is input to the modulation device 402 of this communication device 400 from the memory 304 and transferred to the master station.

Note that the power source 200 is constituted by a solar cell, a storage battery, etc., and is capable of stably supplying power for a long period of time depending on its own ability.

Next, the operation of the above embodiment will be explained. When polling is performed from the master station to the slave station, if the output data from the sensor 100 is changing and is in an uncertain state, that is, in the Busy state, the switch SE becomes ONJ and a Busy signal is generated. .

This Busy signal becomes a high level signal by the inverter 308 and is supplied to the AND310.

Since the polling signal is supplied to AND3]0, an output signal is generated from AND310, and the timer 31
2 starts the timing operation. At the same time, timer 3
12, the modulating device 402 is activated, causing the modulating device 402 to generate an empty word, and transmitting the empty word from the communication device 400 to the master station. The master station that receives this empty word recognizes that the slave station is in a busy state and is operating normally, and maintains the line established with the slave station that sent the received empty word. (standby state).

When the sensor is stable, switch SE becomes ro F FJ, so an output signal is generated from AND 306, which is supplied to modulator 402 and memory 304, prior to which relay switch R3 is turned "ON" and memory The latest data is loaded into 304, and AND30
The modulation device activated from 6 responds to the latest data in the memory 304, and the modulation data is transmitted to the master station via the communication device. FIGS. 4 and 5 illustrate what has been described above. The timer 312 forcibly sends back data and cancels the standby state of the master station when the SE flaw signal does not turn OFF due to an abnormality in the sensor or the like.

In addition, although the case of an agricultural and water system was explained in the said Example, this invention is not limited to this in any way, but can also be applied to the system for other measurement objects.

Further, the circuit configuration may be any other configuration as long as it has a similar function.

(G) As described in detail of the invention, according to the telemeter system of the present invention, when polling is applied to the Busy state, empty data is transferred to the master station, and
After the SY is released, the data is updated and the updated data is transferred to the master station, making it possible to collect the latest data without sacrificing the advantage of power savings. It has excellent effects.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing an example of the configuration of an agricultural and water system that is an example of a telemeter system. J is a block diagram showing an example of a slave station of the system in FIG. 1, FIG. 3 is a block diagram showing an embodiment of the telemeter system according to the present invention, and FIG. 4 is a diagram showing a data transmission mode according to the present invention. Fifth
The figure is the time chart. 100...sensor, 200...power supply, 300...
Measurement control device, 304... memory, 312... timer, 400... communication device, 402... modulation device,
RCL...Relay coil, R3...Relay switch. Procedural amendment (method) Showa ri 1p° 2 motion i' D 1, 'If f'l indication Showa S & 1 effect' [ηx + 1st δl? λO juice 3 supplement 11
', then 1 (1'l) ? 1 edition M 1 person 11 places 1:II, 1111111015, Nakahara-ku, Yozaki City, Kanagawa Prefecture (
522) Name Fujitsu Limited 4 Representative Director Address Naka 1+, Yosaki City, Kanagawa Prefecture: 1 &
l:zl) Ill inside] 0] 51fi Ji Showa S? I11
Moon, 3(r+ (i@口9also4figure(1) Mayo station ho;su>buto i (2n parent station Borisig' 1110E Yogoyoko□

Claims (2)

[Claims] (1) A sensor means that outputs measured data and also outputs a signal indicating that the data is uncertain; a communication means that communicates with a master station; A telemeter system comprising: data transmission control means for causing the communication means to transmit control information to a master station when such occurrence occurs. (2) The telemeter according to claim 1, wherein the control information is an empty word, and the empty word is used to maintain a continuous line between the master station and the empty word sending slave station. system.