JPH03262928A - Gas meter - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a gas meter that detects gas flow rate, etc. using a microcomputer. [Prior Art] Gas flow meter side in a place with a poor installation environment In order to do
A gas meter is known that operates as a gas flowmeter by driving a microcomputer with a battery.Users have traditionally requested that the gas meter in this building be able to withstand use for approximately 10 years. For this reason, % open IM
As in No. 58-88533, the microcomputer is stopped until an abnormality is detected, and when an abnormality is detected, the microcomputer is started and the gas supply is automatically cut off, thereby saving battery power consumption. [Problems to be Solved by the Invention] However, in the above proposal, the micro-combination system does not operate under normal conditions, so processing for communicating flow rate measurement results to the host device and other gas meter functions are required. There was a problem that the control process could not be executed by a microcomputer.For this reason, the applicant of this application
In the issue (November 1999 1O Hijigeki), we proposed a gas meter that would intermittently drive the Microcombi Island-Yu.
Even in normal conditions, the microcomputer is used to reduce power consumption. However, the above proposal still has room for improvement in reducing power consumption.

Therefore, in view of the above-mentioned points, it is an object of the present invention to provide a gas meter that can be controlled by a microcomputer in a normal state and can further reduce power consumption. In order to achieve such an object, the present invention provides a microphone 1:
In a gas meter that monitors the supply state of gas supplied by an I combiator, for each type of software program to be executed by the micro combi-air, the allowable arithmetic processing speed for the software program is determined in advance, and the arithmetic processing speed is determined in advance. storage means for storing speed information representing speed; clock signal generation means for generating a clock signal for driving the microcomputer, the power consumption of which is proportional to the oscillation frequency of the clock signal; and the microcomputer. The invention is characterized in that it comprises a control means for instructing the clock signal generation hand plate to perform an oscillation 8 mantissa corresponding to the software program to be executed based on the speed information in the storage means when the software program is executed.

[For production]

In this case, a software program executed by a microcomputer in a gas meter.

Recognizing that there are control processes that require high-speed processing and control processes that do not require such high processing speeds, we have changed the frequency of the microcomputer-driving clock to correspond to the arithmetic processing speed of the software program. As a result, it is no longer necessary to drive the microcomputer at a fixed clock frequency compatible with high-speed processing, as in the past, and the power consumption of the clock signal generation means is reduced. [Example] Below, figure? FIG. 1 shows the basic structure of an embodiment of the present invention. The gas meter in this embodiment monitors the supply state of gas supplied by a microcomputer 100. The storage means 200 stores speed information representing a predetermined arithmetic processing speed. This arithmetic processing speed is determined for each type of software program to be executed by the microcombi. Microcombi, -
The power consumption of the clock generating means is proportional to the oscillation frequency of the clock signal.

When the software program of the microcombination unit is executed, the control means 400 instructs the clock signal generation means to specify an oscillation frequency corresponding to the software program to be executed based on the speed information of the storage means 200. 500 measures a certain period of time that exceeds the execution time of the software program, and intermittently drives at least the above-mentioned microcomputer C in response to a timing end signal.The second part indicates a specific circuit Ik of the embodiment of the present invention. In, i amount detection-rigid 2. External sensor 3, cutoff valve 4. :i! i-Shinkai Ayu 5 and clock generation episode w110
is connected to the microcomputer l. The microcomputer l is connected to the microcomputer l.
), program memory, work memory.

Built-in clockwise rotation 11i51-1. The program memory contains a software program for executing the following processes and a system program that defines the execution order of this program. ! This system program also contains speed information, which will be described later, corresponding to each execution program. Therefore, the program memory operates as a storage means. The control processing executed by the microcomputer 1 is as follows. The process is as follows: (1) Meter processing that inputs a signal of the flow rate detected by the flow rate detection circuit 2 and monitors whether the flow rate of the supplied gas is within a specified range. (2) Processing of the gas detected by the external sensor 3. External sensor detection process to monitor whether the pressure is within a specified range (3) Process to close the shutoff ff4 in response to the occurrence of an abnormal situation in items (1) and (2) above (4) Above (5) Process of calculating the amount of gas used in relation to (1) above (1) to (5)
Communication processing that transmits information obtained through the processing related to item 4) to the host device and receives operation instructions etc. from the host device.Programs that execute such processing are made into subroutines for each type, and can be easily accessed from the system program. A 3-bit clock selection signal is sent from the microcontroller 1 to the clock generation circuit 10 in order to switch the operating clock each time this software program is executed. Since the microcomputer 1 in this example has a clock circuit 1-1, a clock generation circuit 9 for driving the clock Ml-1 is externally connected to the clock generation circuit 1 (
HX, 100 KHz and 500 KHz, respectively
.

0 oscillation circuits 6 to 8 that generate clock signals with an oscillation frequency of IMHz, and the selected oscillation path becomes operational by the clock selection signal from the microcomputer 1. Clock signal selection in such a circuit The operation for this will be explained with reference to the third spoon. ・Figure 3 shows the execution control procedure of the microcomputer 1. In the clock circuit 1-1, when a certain period of time is counted by counting the clock, the time is counted. Internal C due to end signal
The PU is caused to start (start up) the control procedure shown in FIG. Note that the low-frequency clock clock mentioned above is used as the operating clock at this time.The CPU reads the system program in units of program instructions, and determines the type of subroutine program to be executed by the name of the subroutine program or the storage address number. identify (third district steps 810-520).

As a result of this identification, if a processing program that does not require high calculation processing speed, such as a meter processing program or external sensor detection processing, is to be executed, the speed information in the system 10 grams, in this example, (PAO=ゝL
', PAI='L#P A ='H'), a selection signal for specifying the oscillation circuit is created using the information that defines the level of the 3-bit selection signal, such as
Thirty-six 100KHz clock signals are selected (third
- Steps 820 to 830 → 831, 840 → 541
)・Using the same processing procedure, for the arithmetic processing program (PAO='L', PAI='H', PA2=%
A selection signal (L#) is created, which instructs the microcombi controller to select the 500 KHz clock signal of the second oscillation circuit 7 (steps 820 to 850 in FIG. 3).
→851)・ Also, when executing communication processing, (PAO='H').

A selection signal of PA1=%L', PA2='L' is created and the IMHz clock of the third oscillation circuit 8 is selectively inputted to the microcomputer (stay 7820 in Fig. 3).
~S6o-+s61) - Therefore, the C in the microcomputer when creating the above selection signal
The PU operates as a control means.The processing program to be executed is executed in synchronization with the clock signal selected above.In addition, if an abnormality occurs, the abnormality detection of the meter processing program and external sensor detection program is performed. In response, the cutoff processing program starts the first clock oscillation cycle ji! 6 clock signals.

In this way, the microcombi 1st sequentially executes a series of programs for each gas meter function in synchronization with the corresponding clock signal. , starts the timer function of the clock circuit 1-1 and automatically sets the standby or stop state.

Hereinafter, by repeatedly executing the above-mentioned procedure, a part of the control processing program is executed using a low-frequency clock signal with low power consumption while the combiator 1 is being driven intermittently. As a result, the clock generation circuit 10 Since power consumption is further reduced, the life of the pond can be further extended.

In addition to this embodiment, the following examples can be cited: 1) Since this embodiment uses a microcomputer with a clock circuit (function), the third program is started using the clock signal for the clock circuit. ing. However, when an external clock circuit or timer is connected to the micro ambiator, after a certain period of time has been counted, the time count end signal is used to start the micro combinatorial clock circuit and the lowest frequency startup clock generation circuit. Thereafter, the microcombination unit selects and instructs the clock signal for the execution program. 2) In this embodiment, the oscillation circuit 6 uses a plurality of crystal oscillators.
8 constitute the clock generating circuit 10, but other clock generating circuits whose oscillation frequency and power consumption are proportional can be used. However, an oscillation circuit that uses a frequency divider circuit to change the oscillation frequency consumes more power than the above-mentioned oscillation circuit, and is not preferable because the oscillation frequency and power consumption are inversely proportional.

3) In this embodiment, an example is shown in which four clock signals are used, but the number of clock signals (9) may be determined in accordance with the arithmetic processing speed of the software program. 4) In this embodiment, this clock signal is used. Although we have shown an example in which the present invention is applied to an intermittent drive microcomputer proposed by The micro two-microcombi is connected at once, and a processing instruction for setting a selection signal, that is, a clock frequency, to the clock generation circuit IO is provided at the beginning of the subroutine program to be executed or before the execution instruction of the subroutine program @5) Execution If there are more target software programs than types of clock signals, it is a good idea to memorize the types of software programs and selected clocks in table form, and refer to this table to select the clock that is compatible with the software 10g. In the case of this example, when the execution program is often rewritten or changed, it is sufficient to update only the table contents, and there is an advantage that there is no need to rewrite the entire system program.

〔Effect of the invention〕

As explained above, the present invention reduces the power consumption of the clock generation means by variably setting the frequency of the drive clock signal input to the microcombinator.As a result, the life of the power supply battery is reduced. It is possible to extend the number of gas meters that can be used.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the basic configuration of an embodiment of the invention, FIG. 2 is a block diagram showing a specific circuit 11 of the embodiment of the invention, and FIG. 3 is a block diagram showing a specific circuit 11 of the embodiment of the invention. This is a 70-chart showing the control procedure. 1: FF illustration combinator, 1-1: Clock circuit, 6-
8: Oscillation circuit, 10: Clock generation circuit O Kuto Patent Attorney
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Claims (1)

[Claims] 1) In a gas meter that uses a microcomputer to monitor the supply status of supply gas, for each type of software program that is to be executed by the microcomputer, an allowable calculation processing speed for the software program is determined in advance; a storage means for storing speed information representing an arithmetic processing speed; a clock signal generating means for generating a clock signal for driving the microcomputer, the power consumption of which is proportional to the oscillation frequency of the clock signal; The present invention is characterized by comprising control means for instructing the clock signal generation means to execute the software program and the corresponding oscillation frequency based on the speed information in the storage means when the software program is executed by the microcomputer. gas meter.