JPH0511455Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an electronic device with a pressure sensor that measures altitude and water depth using a pressure sensor.

[Prior Art and Problems] Hitherto, electronic wristwatches with depth gauges that are equipped with pressure sensors and that measure and display water depth have been commercialized.

In this electronic wristwatch with a depth gauge, the pressure sensor is used only to measure water depth, and is of no use during normal watch use, and the function and mounting space of the pressure sensor are wasted.

Therefore, the applicant of the present application devised an electronic device with a pressure sensor that can measure not only water depth but also altitude with a single pressure sensor, and previously filed an application (Japanese Patent Application No. 61-27208,
(Application filed on February 10, 1986).

By the way, since the pressure sensor consumes a large amount of current, the battery will quickly run out if it is constantly driven, so it is designed to be driven intermittently at regular intervals. When driving a pressure sensor at a constant cycle,
A long drive cycle reduces power consumption, but it is difficult to obtain accurate data, and a short drive cycle allows accurate data to be obtained moment by moment, but has the disadvantage of increasing current consumption. Generally, it is used as an altimeter for walking mountain climbing, but in this case the ascending and descending speed is slow and an error of several tens of meters is not a big problem, but when used as a depth meter, the ascending and descending speed is fast and the error is several meters. Accurate data is always required because even if there is an error, it can affect human life.

Therefore, when measuring water depth and altitude with a single pressure sensor, shortening the drive cycle allows accurate water depth measurement, but even when used as an altimeter, the pressure sensor is driven at short time intervals, resulting in wasted power consumption. be done. Furthermore, although the current consumption can be reduced by lengthening the driving cycle, there is a drawback that accurate water depth cannot be measured.

[Purpose of the invention] This invention was made in view of the above-mentioned circumstances, and the purpose is to provide an electronic device with a pressure sensor that consumes less power while satisfying the accuracy required by the measurement target. do.

[Main points of the invention] In order to achieve the above objectives, this invention drives the pressure sensor at a predetermined first cycle when measuring water depth, and drives the pressure sensor at the first cycle when measuring altitude. The gist is that the driving is performed at a predetermined second period that is longer than the period.

[Example] The present invention will be specifically described below using an example. In this embodiment, the present invention is applied to a digital electronic wristwatch.

FIG. 1 shows a block circuit of this embodiment. A reference clock signal of, for example, 32,768 Hz, which is constantly output from the oscillation circuit 1, is divided into a predetermined frequency by the frequency dividing circuit 2, and sent to the timekeeping circuit 3, as well as to the key input section 4, the control section 5, and the sensor control circuit 8. It is sent as clock signal a. The clock circuit 3 is a circuit that counts the sent signals and sends them as time data to the display switching circuit 6. The key input section 4 is provided with various keys, and is a circuit that sends key input signals c and c' to the control section 5 and the sensor control circuit 8, respectively, depending on the operated key. The control unit 5 performs various processes using the key input signal c and the built-in microprogram, and sends the control signal b to the frequency dividing circuit 2, the clock circuit 3, and the display switching circuit 6, and the control signal b to the sensor control circuit 8. ₁ ′～
This is a circuit that sends out each of b ₄ ′. The sensor control circuit 8 has the configuration described below, receives the clock signal a, the key input signal c', and the control signals _b1 ' to _b4 ', and sends an operation command signal _e1 to the sensor output amplification circuit 9 and the pressure sensor 11. , and the operation command signal _e2 to the A/D conversion circuit 10, respectively. The pressure sensor 11 is a circuit that detects the atmospheric pressure or water pressure at the location where the present embodiment is placed only when the operation command signal _e1 is sent, and sends the detected output to the sensor output amplification circuit 9. . Similar to the pressure sensor 11, the sensor output amplification circuit 9 receives an operation command signal.
This circuit operates upon receiving the signal _e1 , amplifies the detection output from the pressure sensor 11, and sends it to the A/D conversion circuit 10. The A/D conversion circuit 10 operates when receiving the operation command signal _e2 , converts the amplified pressure detection output from the sensor output amplification circuit 9 into a digital quantity, and uses this as pressure data to be sent to the control unit 5.
This is the circuit that sends the signal to. At this time, the control unit 5 calculates the altitude or water depth of the current point from the pressure data, stores this, and sends it to the display switching circuit 6. The display switching circuit 6 converts the received time data or altitude or water depth data into a control signal b from the control unit 5.
This circuit selectively sends the data to the display device 7 based on the information, and switches the display on the display device 7. Then,
The display device 7 displays time data or altitude data at the current point.

FIG. 2 shows the circuit configuration of the sensor control circuit 8 described above in detail.

This sensor control circuit 8 includes an AND gate 24 into which the second carry (control signal b ₅ ') from the control section 5 is introduced, an AND gate 25 into which the minute carry (control signal b ₃ ') is introduced, and these gates. A carry selection circuit 8a that sends an opening/closing control signal to the AND gate, and a second carry from the AND gate 24 or a minute carry from the AND gate 25 are introduced, and based on these, the operation command signal _e1 or _e2 is sent out. and an operation command signal generation circuit 8b.
In the carry selection circuit 8a, when the time change of the measurement data is large during altitude measurement (such as when measuring while climbing a mountain by car), the control signal b ₁ ' that becomes H level and the altitude measurement is started. The output of the NOR gate 20, which receives the key input signal c' which becomes H level for a certain period of time when a key is operated, is inverted by the inverter 21 and sent as a reset signal to the delay flip-flops DF1 and DF2. Minute carry signal to inverter 33
In the delay flip-flops DF1 and DF2, which use the inverted signal as the input clock signal, a fixed voltage V _DD is introduced into the delay flip-flop DF1, and the output thereof is input to the delay flip-flop DF1.
It has been introduced in 2. The output of the NOR gate 22, which receives a signal obtained by inverting the output signal from the delay flip-flop DF2 by the inverter 32 and a control signal b ₂ ' that becomes H level during water depth measurement, is directly connected to the AND gate as an opening/closing control signal. 25 and is inverted and applied to AND gate 24.

Next, the operation command signal generation circuit 8b will be explained. This consists of an RS flip-flop 35 consisting of NOR gates 26 and 27, a set signal as the output of AND gate 24 or 25, and a reset signal as a control signal _b4 ', and a delay flip-flop DF.
2X, the output signal of the RS flip-flop 35 and the delay flip-flop DF to this output signal.
An OR gate 29 and an AND gate 30 each input a signal with a constant delay of 2X.
Consisting of Delay flip-flop DF2X above
The above-mentioned clock signal a, which is inverted by an inverter 28, is introduced into the clock terminal of the pressure sensor 1, and the output signals of the OR gate 29 and the AND gate 30 are sent to the pressure sensor 1 as operation command signals _e1 and _e2 , respectively.
1 and the A/D conversion circuit 10.

Next, the operation of this embodiment will be explained.

First, the operation when used as a depth meter will be explained. In this case, the control signal b ₂ ′ sent from the control unit 5 to the sensor control circuit 8 by the key operation of the key input unit 4 becomes H level, so that the NOR gate 2
The output signal of 2 becomes L level, and the AND gate 25 which directly uses this as an opening/closing control signal is closed.
On the other hand, the AND gate 24, which inverts this signal with the inverter 23 and uses it as the opening/closing control signal, is opened. Therefore, the second carry signal is introduced from the control section 5 to the operation command signal generation circuit 8b via the AND gate 24. As a result, as shown in FIG. 3a, the output of the RS flip-flop 35 goes to H level in time with the rise of the second carry signal, and the output of the delay flip-flop DF2X goes to H level in time with the clock signal immediately after that. become. and,
The former is a reset signal (control signal) from the control unit 5.
_b4 ') returns to the L level, and the latter returns to the L level by the clock signal immediately thereafter. Therefore, the operation command signal _e2 , which is the output of the AND gate 30, is output only while both of the above are at the H level, and the operation command signal _e1 , which is the output of the OR gate 29, is a reset signal from the moment the second is carried out. It will only be available until it is available. Therefore, the sensor output amplification circuit 9, A/D conversion circuit 10, and pressure sensor 11 receive these operation command signals and operate only during that time.
will operate for a certain period of time every time there is a second shift.

Next, we will explain the operation immediately after starting to use it as an altimeter.

In this case, the control signal b ₂ ' is set to L level by operating the key of the key input section 4, but at this time, the key input signal c' sent from the key input section 4 due to the key operation is extremely short. It will be at H level for only a certain amount of time. While this key input signal c' is at H level, the output of inverter 21 is at H level, delay flip-flops DF1 and DF2 are reset (see A in FIG. 8b), and the output of inverter 32 is at H level.
Therefore, the output of the NOR gate 22 becomes the L level, and the AND gate 25 is closed and the AND gate 24 is opened. For this reason, a second carry is introduced into the operation command signal generating circuit 8b, and the same operation as in the case of the water depth gauge described above is performed. That is, every time there is a second gain, a measurement operation is performed for a certain period of time, and the result is converted into a high level by the control section 5 and displayed on the display device 7.

Immediately after a very short period of time during which the key input signal c' is at the H level has elapsed, the reset of the delay flip-flops DF1 and DF2 is released; Since there is no change in the input, it is a Delay flip-flop.
There is no change in the outputs of DF1 and DF2, therefore there is no change in both inputs of the NOR gate 22, and there is no change in the control of the AND gates 24 and 25 (see B in FIG. 3B). Therefore, there is no change in the operation command signals e ₁ and e ₂ , and the above-mentioned one-second measurement operation and the like continue.

Furthermore, when the above-mentioned offset occurs, the clock inputs to the delay flip-flops DF1 and DF2 change, so from that moment on, the output of the delay flip-flop DF1 becomes H level, but due to the existence of a time delay. , the output of the delay flip-flop DF2 remains at the L level and does not change (see d in FIG. 3b). Therefore, there is no change in both inputs of the NOR gate 22, and therefore there is no change in the control states of the AND gates 24 and 25, and the above-mentioned one-second measurement operation, etc., continues.

Furthermore, when there is a minute carry again, the clock input to the delay flip-flop DF2 changes, and at this time, the output of the delay flip-flop DF1 is input to the delay flip-flop DF2, and the output of the delay flip-flop DF1 is input to the delay flip-flop DF2. The output of step DF2 changes to H level (see E in Figure 3b). Therefore, both inputs of the NOR gate 22 are at H level, the AND gate 24 is closed, and the AND gate 25 is opened. Therefore, from now on, the operation command signal generation circuit 8
Minute carry is introduced in b. In this operation command signal generation circuit 8b, the same operation as when the seconds carry is introduced when measuring the water depth described above is started every time the minutes carry is introduced, and after a certain period of time, the controller 5 sends the Noah gate 26 This continues until a reset signal (control signal b ₄ ') is sent to .
That is, after 1 to 2 minutes have elapsed from the start of altitude measurement, operation command signals e ₁ and e ₂ are sent out from the sensor control circuit 8 for a fixed period of time every minute, altitude measurement is performed based on these signals, and the results are displayed on the display device 7. will be displayed.

By the way, when measuring the altitude, the control unit 5 converts the pressure data from the A/D conversion circuit 10 into altitude data as described above and sends it to the display device 7 via the display switching circuit 6. minutes ago)
The altitude data at and the altitude data related to the current measurement are compared, and if there is a large change in the altitude data, a control signal b ₁ ' is sent to the NOR gate 20 of the carry selection circuit 8a. In this case, as in the case immediately after the start of altitude measurement described above, one of the inputs to the NOR gate 20 is at L level and the other is at H level.
Therefore, the same operation as immediately after the start of altimeter measurement is performed (see FIG. 3b), and the altitude measurement operation is performed at a cycle of 1 second for 1 to 2 minutes.

As described above, in this embodiment, when measuring water depth, 1
Measurement is performed for a certain period of time at a second cycle, and when measuring altitude, it is measured at a 1 second cycle immediately after the start, at a 1 minute cycle thereafter, and at a 1 second cycle when there is a significant change in altitude.
Each performs measurement operation for a certain period of time.

Note that this invention is not limited to the above-mentioned embodiments, and can be modified and applied in various ways without departing from this invention. For example, in this embodiment, the cycle of the measurement operation is changed only when measuring the altitude, but it goes without saying that the cycle may also be changed in the depth measurement operation depending on the usage situation.

[Effects of the invention] As detailed above, this invention drives the pressure sensor at a predetermined first period when measuring water depth, and at a predetermined period longer than the first period when measuring altitude. By driving at the determined second cycle, current consumption can be reduced while satisfying the accuracy required by water depth and altitude.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram of an embodiment of the present invention.
FIG. 2 is a circuit diagram showing the sensor control circuit in FIG. 1 in detail, and FIG. 3 is a time chart showing the operation of the above embodiment. DESCRIPTION OF SYMBOLS 1... Oscillation circuit, 2... Frequency dividing circuit, 3... Timing circuit, 4... Key input section, 5... Control section, 6...
Display switching circuit, 7...Display device, 8...Sensor control circuit, 9...Sensor output amplification circuit, 10...
A/D conversion circuit, 11...pressure sensor, 35...
RS flip-flop, 8a...carry selection circuit,
8b...Operation command signal generation circuit.

Claims (1)

[Utility Model Claims] An electronic device with a pressure sensor comprising: a single pressure sensor; designation means for designating either depth measurement or altitude measurement; drive control means for driving the pressure sensor at a predetermined first period when depth measurement is designated by the designation means, and for driving the pressure sensor at a predetermined second period longer than the first period when altitude measurement is designated; and means for determining depth data from the pressure detected by the pressure sensor driven by the drive control means when depth measurement is designated, and for determining altitude data when altitude measurement is designated.