JP4356926B2 - Electronics - Google Patents

Description

  The present invention relates to an electronic apparatus having a microcomputer and a non-volatile memory, and more particularly to an electronic apparatus that notifies the occurrence of an abnormality when communication of the non-volatile memory is poor.

As a specific example of an electronic device having a microcomputer and a non-volatile memory, an alarm device that issues an alarm upon detection of a sensor will be described as an example.
This type of alarm is combined with a single unit to detect various abnormalities. For example, gas alarm, incomplete combustion, and fire can be detected by one alarm. Products have been released. Such an alarm device can be equipped with a non-volatile memory that has become easy to obtain due to a low price. This makes it possible to automatically perform various adjustments / settings simply by incorporating non-volatile memory data at the time of alarm production, or simply replace non-volatile memory for alarm devices that have already been sold and installed. It is possible to add a storage function for new alarm device operation information.

  Such an alarm device includes, for example, a sensor, an alarm output unit, a nonvolatile memory, and a microcomputer. The nonvolatile memory stores setting condition data such as a driving condition, an input condition, or an operating condition. The drive condition is a condition that the type of sensor to be used is changed according to the detection target, or the level value for issuing an alarm is changed. The input condition is a condition such as calibration of the input signal. The operating condition is a condition of the alarm output unit such as a notification time.

  The alarm device has different characteristics by appropriately changing the driving conditions, input conditions, or operating conditions to the optimum conditions according to the sensor type and characteristic variations, the installation site conditions, and the user's request. One or more types of sensors can be used. Therefore, as described above, the alarm device is replaced with a non-volatile memory in which setting condition data set in advance as optimum conditions is stored, and the microcomputer reads out such setting condition data to perform various settings. Gas detection / alarm processing is performed under a predetermined condition in accordance with a signal input from the sensor.

  In such an alarm device, as described above, the microcomputer reads the setting condition data stored in the non-volatile memory by communication and determines the operation of the alarm device. However, communication failure occurs when electromagnetic external noise is received while the microcomputer and the nonvolatile memory are communicating.

If the data communicated between the microcomputer and the non-volatile memory changes due to this communication failure, the microcomputer or non-volatile memory misrecognizes the data and the alarm operates under the incorrect setting condition data. Normal alarm processing may not be performed.
In extreme cases, the microcomputer or nonvolatile memory may malfunction and malfunction, and normal alarm processing may not be performed.
In any case, there is a problem that the operation of the alarm device may be hindered.
Therefore, in recent years, a general-purpose gas detection device with improved noise resistance performance as described in Patent Document 1 has been proposed. In the apparatus described in Patent Document 1, the same data is written in the nonvolatile memory several times to back up the data, thereby improving the noise resistance performance.

Japanese Patent Application Laid-Open No. 11-203575 (Claims, paragraph [0010, FIG. 6 etc.)

  In the prior art described in Patent Document 1 described above, when there is a limit on the capacity of the memory or when the nonvolatile memory fails, the alarm device is installed while hindering the operation of the alarm device. There was a possibility that it could not work. In general electronic devices as well as alarm devices, a function capable of detecting such a failure of the nonvolatile memory has been required.

  Therefore, the present invention has been made to solve the above-described problems. The object of the present invention is to indicate that “the electronic device is abnormal when the operation of the electronic device is hindered due to electromagnetic noise or failure of the nonvolatile memory. ”Can be notified to the user (hereinafter, notifying such abnormality of the electronic device is simply referred to as“ notification ”and distinguished from the“ reporting ”by the gas detection described above), and is highly reliable. To provide electronic equipment.

In order to solve the above-described problem, an electronic device according to the first aspect of the present invention provides:
Non-volatile memory ;
And microcomputers,
A sound source IC connected to the microcomputer;
An amplifier circuit connected to the output side of the sound source IC;
A speaker connected to the amplifier circuit;
Display circuit control means connected to the microcomputer;
A plurality of lamps controlled via the display circuit control means;
With
The non-volatile memory and the microcomputer communicate various data, and an alarm is issued by the plurality of lamps and the speaker to detect a gas leak, incomplete combustion, or fire heat and to give an alarm. In electronic equipment related to
The microcomputer is
Writing means for writing data to the nonvolatile memory;
A reading means for reading the written data from the nonvolatile memory;
A determination means for determining whether the written data and the read data are the same, and determining that the communication is good if they are the same, and that the communication is bad if they are not the same;
When it is determined that the communication is poor, a sound notification at the time of abnormality through the sound source IC and the amplifier circuit and a lamp display at the time of abnormality through the display circuit control means are performed, and an alarm device is given to the user by sound and light. Abnormality notification means for notifying that there is an abnormality,
Have a communication error check means at the time of writing, including, also,
A reading means for reading the same data twice from the nonvolatile memory;
A determination means for determining whether or not the data read twice is the same, and determining that the communication is good if the data is the same, and that the communication is bad if the data is not the same;
When it is determined that the communication is poor, a sound notification at the time of abnormality through the sound source IC and the amplifier circuit and a lamp display at the time of abnormality through the display circuit control means are performed, and an alarm device is given to the user by sound and light. Abnormality notification means for notifying that there is an abnormality,
Characterized in that it have a read time of communication abnormality checking means including.

The electronic device of the invention described in claim 2 is:
The electronic device according to claim 1,
The reading communication abnormality check means includes:
Said reading means and said determining means a plurality of times by repeatedly function, and wherein the means der Rukoto a plurality of times the determination of the communication quality.

In the present invention,
(1) When reading data from the non-volatile memory, read twice and check that there is no difference in the data.
(2) When writing data to the non-volatile memory, read again after writing, and check that there is no difference between the written data and the read data.
These checks make it possible to determine the success or failure of communication between the microcomputer and the nonvolatile memory, and to detect an abnormality in the nonvolatile memory.

  Further, by repeating the operation check of (1) a plurality of times and determining the communication abnormality of the nonvolatile memory based on the result, it is possible to prevent abnormality determination due to a communication failure due to temporary noise or the like. An electronic device that performs reliable communication abnormality detection has been realized.

  When it is determined that communication with the non-volatile memory is abnormal by the above means, the microcomputer notifies the user of light, sound, and electronic information by sound notification, LED display, and external output circuit operations. It is now possible to notify the device that it is abnormal and prompt the inspection and replacement of the electronic device.

  According to the present invention, when an operation of an electronic device is hindered due to electromagnetic noise or a failure of a nonvolatile memory, it is possible to notify a user that “the electronic device is abnormal”, and a highly reliable electronic Equipment can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, in order to make the description more specific, an example of an electronic device will be described by taking as an example a gas alarm device that needs to detect a failure quickly because it leads to a disaster.
First, this embodiment is an example of a combined alarm device that detects gas leakage, incomplete combustion such as CO (carbon monoxide) gas, heat in a fire and issues an abnormality by an alarm sound, The circuit block is shown in FIG.

  In FIG. 1, 20 is a commercial power supply, 21 is a step-down power supply circuit, 22 is a rectifying / smoothing circuit, and a constant DC power supply voltage output from the rectifying / smoothing circuit 22 is a microcomputer (to be described later). (Hereinafter simply referred to as a microcomputer) 10, a gas sensor control / monitoring circuit 23, a fire sensor control / monitoring circuit 24, various lamps 41 to 44, and the like.

The microcomputer 10 includes sensor control means 11 for controlling the gas sensor and fire sensor, city gas detection means 12 for detecting city gas from the output of the gas sensor, and CO gas for detecting CO gas from the output of the gas sensor. Detection means 13, fire (heat) detection means 14 for detecting fire (heat) from the output of the fire sensor, display circuit control means 15 for controlling various lamps 41 to 44, etc., voltage output circuit 25, an external output control means 16 for controlling an external circuit such as a non-voltage output circuit 26, and a communication check means 17 for checking the communication between the nonvolatile memory 28 and the microcomputer 10 for abnormality.
The means 11 to 17 are constituted by hardware and software.

  The gas sensor control / monitoring circuit 23 is connected to the sensor control means 11, the city gas detection means 12, the CO gas detection means 13, etc. in the microcomputer 10, and starts processing of detection signals of a semiconductor gas sensor (not shown). Control and monitoring operations are performed. The fire sensor control / monitoring circuit 24 is connected to the sensor control means 11, the fire (heat) detection means 14 and the like in the microcomputer 10, and performs control such as processing of a detection signal of a fire sensor (not shown). -Perform monitoring operation.

Further, the microcomputer 10 has a voltage output circuit 25 capable of outputting voltages of 0V, 6V, 12V, and 18V, and a non-voltage output circuit that outputs a warning signal due to a contact short circuit when a contact is normally opened and a fire is detected. 26 is connected.
Further, the microcomputer 10 is connected with a sound source IC 27 for outputting an alarm by sound at the time of gas detection / abnormality, an amplifier circuit 29 connected to the output side, and a speaker 30 as a specific example of the alarm output means. Has been.

  The various lamps 41 to 44 include a power lamp 41 composed of a green LED, an incomplete combustion alarm lamp 42 composed of a yellow LED, a gas leak alarm lamp 43 composed of a red LED, and a fire alarm lamp 44 composed of a red LED. Yes.

In the above configuration, gas leakage and incomplete combustion are detected by a semiconductor gas sensor. The gas sensor is used in a constant voltage power supply connected in series with a fixed resistor. The gas sensor impedance is lowered by gas at the time of gas leakage or incomplete combustion, and the city gas detection means of the microcomputer 10 according to the detected gas concentration. 12 or the CO gas detection means 13 outputs a signal.
The fire sensor detects the temperature with a thermistor, and is used in series with a fixed resistor in a constant voltage power supply like the gas sensor. The fire (heat) detecting means of the microcomputer 10 is used according to the detected temperature at the time of the fire. 14 outputs a signal.

  When the microcomputer 10 determines that an abnormality has occurred from the detection signals of the respective sensors, the microcomputer 10 displays an alarm by the lamps 42 to 44 via the display circuit control means 15, and the voltage output circuit 25, none via the external output control means 16. The voltage output circuit 26 is operated to output an alarm, and the sound source IC 27 is directly controlled by a control means (not shown) to issue an alarm sound.

  Here, the alarm display by the lamps 42 to 44 blinks as a warning when a temperature lower than the temperature determined to be a low concentration gas or fire is detected, for example, and is determined to be a high concentration gas or fire. If a temperature higher than the detected temperature is detected, it is turned on as an alarm, and the lamp is operated according to the abnormal contents such as incomplete combustion, gas leak, and fire, so that the user can It is possible to easily recognize whether a certain degree of abnormality has occurred.

  For example, when a gas leak is detected, the alarm sound using the sound source IC 27 is “whether the gas is leaking”. If the fire is detected, “Fire alarm has been activated. Please check.” If the alarm is abnormal, “Alarm Select a message such as “Please check”. These audio data are stored in the memory of the sound source IC 27.

The voltage output circuit 25 controlled by the external output control means 16 outputs 6V at normal time, 12V at gas leak detection, 18V at incomplete combustion detection, and 0V at alarm failure.
Similarly, the non-voltage output circuit 26 normally has a contact open as described above, and outputs a signal due to a contact short circuit to the outside when a fire is detected.

Next, details from the microcomputer 10 until the alarm sound is emitted from the speaker 30 will be described.
When the microcomputer 10 determines that an abnormality has occurred from detection signals from a gas sensor, a fire sensor, or the like, the microcomputer 10 outputs an address signal that indicates what alarm sound (message) is to be issued to the sound source IC 27. The address signal indicates the address on the memory of the alarm sound in the sound source IC 27, and is selected according to what abnormality is detected by each of the detection means 12-14.

  The sound source IC 27 reads an alarm sound relating to the address instructed from the microcomputer 10 from the memory, converts the digital data into an analog signal by an internal D / A converter, and applies a constant voltage to a reference potential (via a low-pass filter). 0 level) analog signal (AC signal) is output to the amplifier circuit 29. The amplifier circuit 29 amplifies the analog signal output from the sound source IC 27 and outputs the amplified analog signal to the speaker 30. The speaker 30 converts the input analog signal into sound and issues an alarm sound.

  The analog signal from the sound source IC 27 outputs the same potential as the GND level of the sound source IC 27 when not operating, and outputs the reference potential when the sound source IC 27 operates. This is a function that prevents the noise due to the noise from being reported in the non-reporting state, and the reference potential is designed to an arbitrary value by the alarm designer by the external resistance of the sound source IC 27 or the like. It is possible to do. The notification processing is like this.

  The microcomputer 10 of such an alarm device sets conditions by reading preset condition data such as driving conditions, input conditions, or operating conditions from the nonvolatile memory 28. Further, in detail, an EEPROM (Electrically Erasable Programmable Read-Only Memory) is used as the nonvolatile memory 28, and the microcomputer 10 can write new setting condition data.

Next, details of communication between the microcomputer 10 and the nonvolatile memory 28 will be described. In this embodiment, as shown in FIG. 2, the microcomputer 10 and the nonvolatile memory 28 perform four-wire serial communication.
The microcomputer 10 outputs three signals: an operation control signal, a clock signal, and a data output signal 1.
The nonvolatile memory 28 outputs the data output signal 2.

The operation control signal from the microcomputer 10 is a signal for controlling the operation / standby of the nonvolatile memory 28.
The clock signal from the microcomputer 10 is a signal for synchronizing the microcomputer 10 and various communications between the nonvolatile memory 28.
The data output signal 1 from the microcomputer 10 is a signal including a command signal representing the operation content of the nonvolatile memory 28 and a data signal for outputting data to be written to the nonvolatile memory 28 when necessary. Specifically, the command signal is a signal of several bits, and is a signal that causes the nonvolatile memory 28 to execute data output, data input, data erasure, and the like. The data signal is a serial signal of data to be communicated.
The data output signal 2 from the nonvolatile memory 28 is a data signal and is a serial signal of data read from the nonvolatile memory 28.

Next, communication will be described. First, communication for reading data from the nonvolatile memory 28 will be described. FIG. 3A is a timing chart when reading data from the nonvolatile memory 28 (command signal: data output from the nonvolatile memory 28).
In the case of reading data from the nonvolatile memory 28,
(1) The microcomputer 10 transmits an operation enable signal (port level H) as an operation control signal to place the nonvolatile memory 28 in the “operation” state.
(2) The microcomputer 10 outputs the data output signal 1 in synchronization with the clock signal. The data output signal 1 is a command signal for instructing data output from the nonvolatile memory 28.
(3) The nonvolatile memory 28 outputs the data output signal 2 in synchronization with the clock signal of the microcomputer 10. This data output signal 2 is a data signal read by the microcomputer 10.
(4) After completing the reception of the data signal from the nonvolatile memory 28, the microcomputer 10 outputs an operation disable signal (port level L) as an operation control signal to put the nonvolatile memory 28 in the “standby” state. (The above operation is hereinafter referred to as “read operation”.)

Next, communication for writing data to the nonvolatile memory 28 will be described. FIG. 3B is a timing chart when writing data from the nonvolatile memory 28 (command signal: data input to the nonvolatile memory 28).
When writing data to the nonvolatile memory 28,
(1) The microcomputer 10 transmits an operation enable signal (port level H) as an operation control signal to place the nonvolatile memory 28 in the “operation” state.
(2) The microcomputer 10 outputs the data output signal 1 in synchronization with the clock signal. The data signal 1 includes a command signal for instructing data input to the nonvolatile memory 28 and a data signal for data to be written.
(3) The nonvolatile memory 28 stores the data read from the data signal of the data output signal 1 in the nonvolatile memory 28.
(4) After completing the transmission of the data output signal 1 to the nonvolatile memory 28, the microcomputer 10 outputs an operation disable signal (port level L) as an operation control signal to place the nonvolatile memory 28 in a “standby” state. (The above operation is hereinafter referred to as “write operation”.)
In this case, the data output signal 2 is not output.

  In this embodiment, a combination of the read operation and the write operation described above is performed to check a communication error when reading data from the nonvolatile memory 28 and a communication error when writing data to the nonvolatile memory 28.

1) Communication error check when data is read from the non-volatile memory 28 The communication error check when data is read from the non-volatile memory 28 is performed when the microcomputer 10 sets the set condition data (alarm point data, alarm) This is performed when reading the device operation mode setting data) from the nonvolatile memory 28. FIG. 4A is a flowchart of a communication abnormality check during reading.

  A communication abnormality check at the time of reading is started (step S1 in FIG. 4A), and 1 is substituted into the variable N (step S2 in FIG. 4A). This functions as a counter for checking three times when communication is abnormal. Subsequently, a first read operation of reading data A is performed (step S3 in FIG. 4A), and a second read operation of reading data B that is the same data at the same address is performed (step S4 in FIG. 4A). Do. Then, it is determined whether or not data A = data B (step S5 in FIG. 4A). If data A = data B (YES in step S5 in FIG. 4A), it is determined that communication has been performed correctly. The communication abnormality check at the time of reading ends (step S6 in FIG. 4A). As described above, in this embodiment, the “read operation” is performed twice, and a comparison check is performed to determine whether the two read data match.

  If it is determined that data A = not data B, that is, communication is abnormal (NO in step S5 in FIG. 4A), it is determined whether N ≧ 3 (step S7 in FIG. 4A). Since N ≧ 3, that is, N is 1 and the communication abnormality check is still the first time, N is incremented, that is, N = 2 (step S9 in FIG. 4A), and the communication abnormality check is again performed (steps S3, S4, S5). )I do.

  If it is determined that the data A and the data B read in the communication abnormality check again are the same (YES in step S5 in FIG. 4A), the communication abnormality check at the time of reading is terminated because it is not a communication abnormality ( In step S6 in FIG. 4A, if data A = data B is still not satisfied (NO in step S5 in FIG. 4A), it is determined whether N ≧ 3 (step S7 in FIG. 4A), and N is the second time. Therefore, N is incremented, that is, N = 3, and the communication abnormality check (steps S3, S4, S5) is performed again. If data A = data B (YES in step S5 in FIG. 4A), it is determined that communication has been correctly performed, and the reading communication abnormality check is terminated (step S6 in FIG. 4A). If data A = data B is still not satisfied (NO in step S5 in FIG. 4A), it is determined whether N ≧ 3 (step S7 in FIG. 4A). Since N is the third time, a memory failure has occurred. Is determined (YES in step S7 in FIG. 4A), and abnormality notification processing is performed (step S8 in FIG. 4A).

As described above, in the communication abnormality check at the time of reading, the communication abnormality check in steps S3, S4, and S5 is repeated a plurality of times (in this embodiment, three times). Judged 28 abnormalities.
As a result, it is possible to check without determining that the non-volatile memory 28 is abnormal due to a communication failure due to temporary noise or the like. When the microcomputer 10 determines that the non-volatile memory 28 is abnormal, the microcomputer 10 causes an audio notification through the sound source IC 27 and the amplifying means 29, for example, an LED that cannot normally be emitted from the lamps 41 to 44. By performing each circuit operation of display, sound, and external output for display, it is possible to notify the user that the alarm device is abnormal with light and sound.

2) Communication abnormality check at the time of writing data to the nonvolatile memory 28 The communication abnormality check at the time of writing data to the nonvolatile memory 28 is performed by the microcomputer 10 for setting condition data input or set through an operation unit (not shown) or monitoring. This is performed when the detection data obtained by the above is written into the nonvolatile memory 28. FIG. 4B is a flowchart of a communication abnormality check at the time of writing.

A communication abnormality check at the time of writing is started (step S11 in FIG. 4B), a writing operation of writing data C is performed (step S12 of FIG. 4B), and a reading operation of reading data D by accessing the address written immediately before (Step S13 in FIG. 4B), it is determined whether or not data C = data D. If data C = data D (YES in step S14 in FIG. 4B), it is determined that communication has been performed correctly. Then, the communication abnormality check at the time of writing is completed (step S15 in FIG. 4B).
If it is determined that data C = data D, that is, communication is abnormal (NO in step S14 in FIG. 4B), an abnormality notification process is performed as a memory failure (step S16 in FIG. 4B). .

As described above, in the communication abnormality check at the time of writing, a reading operation is performed after the writing operation is performed, and it is determined whether the data written to the nonvolatile memory 28 matches the data read from the nonvolatile memory 28 after writing. If the data does not match, it is determined that the nonvolatile memory 28 is abnormal.
As described above, the communication abnormality check at the time of writing data to the nonvolatile memory 28 is performed by the microcomputer 10 in which setting condition data (alarm point data, alarm device operation mode setting data at the time of alarm device setting, etc.), detection data, etc. are nonvolatile. This is done when writing to the memory 28.

  According to such a communication abnormality check at the time of writing, the abnormality check of the nonvolatile memory 28 can be repeated many times by performing the communication abnormality check with the nonvolatile memory 28 by the microcomputer 10 every time. It can be detected immediately when it occurs. When the microcomputer 10 determines that the nonvolatile memory 28 is abnormal, it is not normal that the microcomputer 10 illuminates all of the voice reports from the sound source IC 27 and the amplifying means 29, for example, the lamps 41 to 44. By performing each circuit operation of LED display and voice / display external output, it is possible to inform the user that the alarm is abnormal by light and sound.

  In addition, since the alarm device of this embodiment performs a communication error check at the time of writing and a communication error check at the time of writing, the communication error check of the nonvolatile memory 28 can be performed reliably. If the nonvolatile memory 28 is abnormal, Since the alarm notifies the user that the alarm device is abnormal, the user can recognize the abnormal operation of the alarm device. Even if an alarm device checks only one of the communication abnormality check at the time of writing or the communication abnormality check at the time of writing, a communication abnormality check is performed and a highly reliable alarm device can be obtained.

  The present embodiment has been described above. In this embodiment, as a specific example of the electronic device, an alarm device in which communication abnormality between the microcomputer and the nonvolatile memory is a problem has been described as an example. However, it goes without saying that the communication abnormality check according to the present invention may be performed on electronic devices other than the alarm device to detect the communication abnormality early. The present invention can be applied to any electronic device having a microcomputer and a nonvolatile memory connected to the microcomputer.

It is a circuit block diagram showing an embodiment of the present invention. It is explanatory drawing explaining the detail of communication with a microcomputer and a non-volatile memory. It is a timing chart (command signal: data output from a non-volatile memory) when reading data from a non-volatile memory. It is a timing chart at the time of writing data from a non-volatile memory (command signal: data input to a non-volatile memory). It is a flowchart of a communication abnormality check at the time of reading. It is a flowchart of a communication abnormality check at the time of writing.

Explanation of symbols

10: Microcomputer
11: Sensor control means 12: City gas detection means 13: CO gas detection means 14: Fire (heat) detection means 15: Display circuit control means 16: External output control means 17: Communication check means 20: Commercial power supply 21: Power supply circuit 22: Rectification / smoothing circuit 23: Gas sensor control / monitoring circuit 24: Fire sensor control / monitoring circuit 25: Voltage output circuit 26: No-voltage output circuit 27: Sound source IC
28: Non-volatile memory 29: Amplifier circuit 30: Speaker 41: Power lamp 42: Incomplete combustion alarm lamp 43: Gas leak alarm lamp 44: Fire alarm lamp

Claims (2)

Non-volatile memory ;
And microcomputers,
A sound source IC connected to the microcomputer;
An amplifier circuit connected to the output side of the sound source IC;
A speaker connected to the amplifier circuit;
Display circuit control means connected to the microcomputer;
A plurality of lamps controlled via the display circuit control means;
With
The non-volatile memory and the microcomputer communicate various data, and detect an alarm from the plurality of lamps and the speaker by detecting the heat of gas leakage, incomplete combustion, or fire. In electronic equipment related to
The microcomputer is
Writing means for writing data to the nonvolatile memory;
A reading means for reading the written data from the nonvolatile memory;
A determination means for determining whether the written data and the read data are the same, and determining that the communication is good if they are the same, and that the communication is bad if they are not the same;
When it is determined that the communication is poor, an audio notification at the time of abnormality through the sound source IC and the amplifier circuit and a lamp display at the time of abnormality through the display circuit control means are performed, and an alarm device is provided to the user by sound and light. Abnormality notification means for notifying that there is an abnormality,
Have a communication error check means at the time of writing, including, also,
A reading means for reading the same data twice from the nonvolatile memory;
A determination means for determining whether or not the data read twice is the same, and determining that the communication is good if the data is the same, and that the communication is bad if the data is not the same;
When it is determined that the communication is poor, an audio notification at the time of abnormality through the sound source IC and the amplifier circuit and a lamp display at the time of abnormality through the display circuit control means are performed, and an alarm device is provided to the user by sound and light. Abnormality notification means for notifying that there is an abnormality,
An electronic apparatus, characterized in that have a read time of communication abnormality checking means including. The electronic device according to claim 1,
The reading communication abnormality check means includes:
Said reading means and said determining means is a plurality of times repeatedly functions, electronic apparatus characterized means der Rukoto performed a plurality of times of communication quality judgment.

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