JP4029463B2 - Communication apparatus and storage medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a communication apparatus in which hook switches are provided in both the apparatus main body and the handset, such as a facsimile apparatus, and a storage medium storing a program for controlling the communication apparatus.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, facsimile machines and telephone devices are provided with a handset for making a call with a partner, and usually a hook switch is provided at a location where the handset of the device main body is installed.
[0003]
Recently, facsimile machines and telephone devices themselves have become more sophisticated and multifunctional, and particularly in facsimile machines, the power consumption associated with image reading and recording operations is large. It is done using. Therefore, the hook switch provided in the apparatus main body of the facsimile apparatus employs a mechanism for opening and closing the electrical connection with the public telephone line based on the power supply current from the external power supply.
[0004]
On the other hand, general public telephone lines are provided with a power supply function in addition to the role of transmitting voice signals. Therefore, in a telephone device or the like connected to a public telephone line, voice signals can be transmitted and received through the telephone line by disconnecting and connecting the line based on the line current even during a power failure. For this reason, some facsimile machines are equipped with a hook switch in the handset in addition to the hook switch on the main body so that a telephone call can be made with the other party via a public telephone line even in the event of a power failure. In such a facsimile apparatus, one hook switch opens and closes an electrical connection with a public telephone line based on a power supply current from an external power source, and the other hook switch opens and closes an electrical connection based on a line current. It is configured. Such two types of hook switches are arranged so as to be linked to each other, and both open and closed states are always matched. For example, when the handset is placed on the apparatus main body after the call is finished, both hook switches are brought into an open state in which the electrical connection with the telephone line is disconnected while being pressed down together.
[0005]
[Problems to be solved by the invention]
However, in the conventional facsimile apparatus provided with two types of hook switches, the opening and closing states of both hook switches may differ from each other depending on how the handset is placed on the apparatus body. In such a case, if the user thinks that the line was disconnected and left it as it is, it is connected to the public telephone line, so it cannot receive the call signal from the other party, Or, there was a problem such as being charged for some time.
[0006]
The present invention has been proposed in view of the above points, and when a problem occurs in the line connection status according to the open / close state of the two types of hook switches, attention is paid by emitting a warning sound or warning light. It is an object of the present invention to provide a communication device that can be prompted, and a storage medium that stores a program for controlling the communication device.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the communication device according to the first aspect of the present invention opens and closes an electrical connection with the communication line for each of the apparatus main body and the main body removable input / output terminal connected to the communication line. The communication device is provided with first and second hook switches for performing sound and has a notification means for emitting sound or light, and detects an open / close signal from the first and second hook switches. An open / close state determination means for determining whether or not there is a difference between the open / close states of the two hook switches, and the notification means when the open / close state determination means determines that there is a difference in the open / close state of the hook switches. And a warning notification control means for generating a warning sound or warning light.
[0008]
According to this communication apparatus, depending on how the input / output terminal is placed with respect to the apparatus main body, the opening and closing states of the first and second hook switches attached thereto may be different from each other. In such a case, the opening / closing signals from both hook switches are detected and it is determined that there is a difference in the opening / closing state, and as a result, a warning sound or warning light is generated when the operations of both hook switches are different. Even when a problem occurs in the line connection status according to the open / close state of the two types of hook switches, the user can be alerted by emitting a warning sound or warning light. Specifically, if the input / output terminal is not placed correctly with respect to the main unit after communication is completed, the warning sound or warning light may be emitted even if the user thinks that the line has been disconnected. Can prompt the user to reposition the input / output terminal, and then place the input / output terminal accurately on the main body of the device, so that the call signal from the other party cannot be received or is charged It is possible to solve problems such as being sustained.
[0009]
The communication line is preferably a public telephone line, for example, but is not limited to this, and may be a dedicated line, or may be wired or wireless.
[0010]
As the notification means, for example, a device that emits a warning sound by a buzzer or a speaker, or a device that emits a warning light by an LED, an LCD, or the like is conceivable. .
[0011]
A communication device according to a second aspect of the present invention is the communication device according to the first aspect, wherein any one of the first and second hook switches is adapted to a line current of the communication line. Based on this, an open / close signal is output.
[0012]
According to this communication apparatus, in addition to the effect of the communication apparatus according to claim 1, one of the first and second hook switches outputs an open / close signal based on the line current of the communication line. Therefore, even when the other hook switch cannot be used due to a power failure or the like, the one hook switch operates normally, so that the connection with the communication line at the time of a power failure or the like can be guaranteed.
[0013]
As the other hook switch, for example, a configuration in which an open / close signal is output based on a current from an external power source or a battery is conceivable, but the hook switch is not limited to an external power source or a battery.
[0014]
[0015]
[0016]
Claims 3 The communication device of the invention described in claim 1 Or Claim 2 The communication apparatus according to claim 1, wherein the apparatus main body is a facsimile apparatus main body.
[0017]
According to this communication apparatus, claim 1 Or Claim 2 In addition to the effects of the communication apparatus described in (1), the present invention can be applied to a facsimile apparatus, and image data can be transmitted and received based on the facsimile communication function.
[0018]
And claims 4 The communication device of the invention described in claim 1 to claim 1. 3 The main body detachable input / output terminal is a transmitter / receiver for inputting / outputting call voice.
[0019]
According to this communication device, claims 1 to 3 In addition to the effects of the communication device described in any of the above, it can be applied to a facsimile device or a telephone device equipped with a handset, and can transmit and receive call voice based on the telephone function via the handset. .
[0020]
Claims 5 The communication device of the invention described in claim 1 Or claims 4 A communication device according to any one of The apparatus main body is provided with line branching means for branching the communication line, and the main body detachable input / output terminal and various types of input / output terminals can be connected via the line branching means. , The various types of input / output terminals are telephone devices including a handset.
[0021]
According to this communication device, the claim 1 Or claims 4 In addition to the effects of the communication device described in any one of the above, for example, it can be used in a usage form in which a telephone device is connected to the main body of the facsimile device.
[0022]
And claims 6 The first and second hook switches for opening and closing the electrical connection with the communication line are respectively connected to the apparatus main body and the main body detachable input / output terminal connected to the communication line. And a storage medium storing a program for controlling a communication device having a notification means for emitting sound or light, and detecting an opening / closing signal from the first and second hook switches. When it is determined that there is a difference between the open / close state of the both hook switches based on the open / close state determination program for determining whether there is a difference between the open / close states of the two hook switches and the open / close state determination program A program including a warning notification control program for generating a warning sound or warning light by the notification means is stored.
[0023]
According to this storage medium, the operation of the communication device according to claim 1 can be realized by operating the CPU based on the stored program.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.
[0025]
FIG. 1 is a circuit block diagram showing a circuit configuration of a facsimile apparatus as an example of a communication apparatus according to the present invention. As shown in FIG. An EEPROM 6, a gate array 7, a codec 8, a DMAC 9, a voice codec 10, a reading unit 11, a recording unit 12, an operation unit 13, a display unit 14, and a sound generation unit 15 are provided in the apparatus main body, and the handset 20 is provided separately from the apparatus main body. It comprises. The CPU 1, NCU 2, RAM 3, modem 4, ROM 5, EEPROM 6, gate array 7, codec 8, DMAC 9, and audio codec 10 are mutually connected by a bus line. The bus line includes an address bus, a data bus, and a control signal line. A reading unit 11, a recording unit 12, an operation unit 13, a display unit 14, and a sound generation unit 15 are connected to the gate array 7. A public telephone line 21 as an example of a communication line is connected to the NCU 2 and a handset 20 is connected as a main body detachable input / output terminal. The NCU 2 is connected to a telephone device 30 as an input / output terminal device different from the facsimile device. The handset 20 and the telephone device 30 are connected via a modular jack or the like provided in the NCU 2.
[0026]
The CPU 1 controls the entire facsimile apparatus. The NCU 2 is connected to the public telephone line 21 and performs network control. The NCU 2 is provided with a line branch circuit (not shown), and the handset 20 and the telephone device 30 are connected via the line branch circuit. The RAM 3 is backed up by a battery (not shown) and stores various data such as audio data and image data. The modem 4 performs modulation of transmission data, demodulation of reception data, and the like. The ROM 5 stores data such as various programs and initial setting values. The EEPROM 6 stores various flags and registration data. The gate array 7 functions as an input / output interface for the CPU 1. The codec 8 encodes facsimile transmission data and decodes facsimile reception data. The DMAC 9 writes and reads data to and from the RAM 3. The audio codec 10 mutually converts an analog audio signal and digital audio data.
[0027]
The reading unit 11 includes a light source, an image sensor, and the like, and outputs an analog image signal. The recording unit 12 includes, for example, an ink jet recording apparatus, and records a received image, a read image at the time of copying, and the like on a recording sheet. The operation unit 13 includes a group of key switches and the like, and outputs an operation signal corresponding to a user operation input. The display unit 14 includes a backlight built-in LCD and the like, and is controlled by the CPU 1 to perform various displays. The sound generation unit 15 includes a speaker or the like, and generates a ringing tone or a warning tone according to the operation status in accordance with a calling signal from the other party.
[0028]
In the above configuration, the handset 20 is for inputting / outputting call voice, and is placed on a predetermined position of the operation unit 13 when not making a call. FIG. 2 is an external perspective view showing the external periphery of the facsimile apparatus. As shown in FIG. 2, the handset 20 and the telephone device 30 are connected via the modular jacks 2a and 2b. In addition, a first hook switch 13a is provided at a predetermined location where the handset 20 of the operation unit 13 is placed. The first hook switch 13a opens and closes the electrical connection with the public telephone line 21 in conjunction with the release / attachment operation of the handset 20, and is based on a power supply current from an external power source (not shown). Is used. On the other hand, a second hook switch 20a is also provided at a predetermined location of the handset 20, and this second hook switch 20a is also used for the attaching / detaching operation of the handset 20, similar to the first hook switch 13a. The electrical connection with the public telephone line 21 is opened / closed in conjunction with each other, and an open / close signal is output based on the line current from the public telephone line 21. That is, when the handset 20 is placed on a predetermined position of the operation unit 13, the first and second hook switches 13 a and 20 a are both opened and electrically connected to the public telephone line 21. Will be cut off. On the contrary, when the handset 20 is detached from the predetermined position of the operation unit 13, the first and second hook switches 13a and 20a are both closed to electrically connect the internal circuit and the public telephone line 21. Keep connected.
[0029]
Explaining the main point, the first and second hook switches 13a and 20a output an open / close signal in the same state in conjunction with each other in the normal normal operation. If the handset 20 is not placed on a predetermined position of the operation unit 13, a difference occurs in the open / close signals from both hook switches 13a, 20a. In such a situation, one of the hook switches is in a closed state and is connected to the public telephone line 21, so that it cannot receive a call signal from the other party or is charged Inconveniences such as being sustained may occur. Therefore, the CPU 1 determines whether or not there is a difference between the states of the hook switches 13a and 20a by detecting an open / close signal from the hook switches 13a and 20a. If it is determined that there is a difference between the open / closed states of the hook switches 13a and 20a, the CPU 1 drives the speaker of the sound generator 15 to generate a warning sound and turns on the LCD backlight. The warning light is generated. Further, when the telephone device 30 is connected via the NCU 2, the telephone device 30 is connected in parallel with the handset 20a via the line branch circuit. If a problem occurs in the line connection status due to the operation of the hook switch, a warning sound and a warning light are generated under the control of the CPU 1. Furthermore, when the external power supply is interrupted, the first hook switch 13a does not output an open / close signal. However, the second hook switch 20a and the hook switch (not shown) of the telephone device 30 are connected to each other even during the power failure. Therefore, the connection with the communication line at the time of power failure is guaranteed.
[0030]
That is, the CPU 1 detects the open / close signal from the first and second hook switches, and both the open / close state determination means for determining whether or not there is a difference between the open / close states of the both hook switches and the open / close state determination means. When it is determined that there is a difference in the open / close state of the hook switch, a warning notification control unit that generates a warning sound or a warning light by the notification unit is realized.
[0031]
The ROM 5 is provided with first and second hook switches for opening and closing an electrical connection with the communication line on each of the apparatus main body and the main body detachable input / output terminal connected to the communication line. A storage medium storing a program for controlling a communication device having a notification means for emitting sound or light, detecting an opening / closing signal from the first and second hook switches, When the open / close state determination program for determining whether there is a difference in the open / close state and the open / close state of the both hook switches based on the open / close state determination program, it is warned by the notification means. A storage medium storing a program including a warning notification control program for generating sound or warning light is realized.
[0032]
The main points of the operation of the facsimile apparatus having the above configuration will be described with reference to the flowchart shown in FIG.
[0033]
FIG. 3 is a flowchart showing a processing procedure according to the line connection status of the facsimile apparatus. As shown in FIG. 3, first, the CPU 1 performs the first and second operations in the state where the line connection process is started. The open / close signal corresponding to the open / close state is detected from the hook switches 13a and 20a (S1). The open / close signal is output as a square wave signal indicated by a voltage / current corresponding to the open / close state of each of the first and second hook switches 13a and 20a.
[0034]
After completing the detection of the open / close signal, the CPU 1 determines whether or not a signal is detected from the first hook switch 13a (S2).
[0035]
When the signal from the first hook switch 13a is detected (S2: YES), the CPU 1 determines that the first hook switch 13a is operating normally based on the power source current from the external power source, Based on the open / close signal from the hook switches 13a, 20a, it is determined whether or not the open / close states of the hook switches 13a, 20a are the same (S3).
[0036]
When the opening / closing states of both hook switches 13a, 20a are the same (S3: YES), the CPU 1 determines whether both the hook switches 13a, 20a are closed based on the detected opening / closing signal (S4). ).
[0037]
When both the hook switches 13a and 20a are in the closed state (S4: YES), the CPU 1 controls the NCU 2 so as to be electrically connected to the public telephone line 21 (S5). That is, a tone signal is notified through the public telephone line 21 when the handset 20 is detached from the apparatus main body by a user or the like and both the hook switches 13a and 20a are both in the off-hook state.
[0038]
Thereafter, the CPU 1 starts a call process for transmitting and receiving normal call voice and call signals (S6). As a result, voice and ringing tone (ringback tone) are transmitted and received through the handset 20 and the numeric keypad of the operation unit 13.
[0039]
After the call process is started, the CPU 1 performs the same process as S3 again, and determines whether or not the open / close states of both hook switches 13a and 20a are the same based on the open / close signals from both hook switches 13a and 20a. (S7).
[0040]
When the open / closed states of both hook switches 13a, 20a are the same (S7: YES), the CPU 1 determines whether both the hook switches 13a, 20a are open based on the open / close signal (S8).
[0041]
When both the hook switches 13a and 20a are in the open state (S8: YES), the CPU 1 controls the NCU 2 to be electrically disconnected from the public telephone line 21 (S9), and a program routine relating to this line connection processing The execution of is terminated. That is, when the handset 20 is placed on the apparatus body by the user or the like and both the hook switches 13a and 20a are both in the on-hook state, the electrical connection state with the public telephone line 21 is released. .
[0042]
In S8, when both the hook switches 13a and 20a are not in the open state (S8: NO), the CPU 1 returns to S7 and executes the same determination process for both the hook switches 13a and 20a.
[0043]
In S7, when the open / close states of the hook switches 13a and 20a are different (S7: NO), the CPU 1 generates a warning sound and a warning light by the speaker and the backlight (S10). That is, when the handset 20 is placed on the apparatus body by a user or the like, but either one of the hook switches 13a and 20a is off-hook because of the poor placement, the public telephone line Therefore, a warning sound and a warning light are generated to note that there is a problem in such a line connection situation.
[0044]
After the warning sound and the warning light are generated, the CPU 1 determines whether or not the open / closed states of both hook switches 13a, 20a are the same (S11), and if determined to be the same (S11: YES), the CPU 1 The generation of the warning light is stopped (S12), and the process proceeds to S8. That is, when the handset 20 is replaced, both the hook switches 13a and 20a are turned on hook, and the generation of the warning sound and the warning light is stopped.
[0045]
In S11, when the opening / closing states of the hook switches 13a and 20a are different (S11: NO), the CPU 1 returns to S10 and continues to generate the warning sound and the warning light.
[0046]
In S4, when both the hook switches 13a and 20a are in the open state instead of the closed state (S4: NO), the CPU 1 returns to S1 and detects the opening / closing signal which is the first process of this program routine.
[0047]
In S3, when the open / close states of the hook switches 13a and 20a are different (S3: NO), the CPU 1 generates a warning sound or a warning light by the speaker and the backlight (S13). That is, when the handset 20 is placed on the apparatus main body, but one of the hook switches 13a and 20a is in an off-hook state due to poor placement or the like, A warning sound and a warning light will be generated in order to note that the placement is bad.
[0048]
After the warning sound and the warning light are generated, the CPU 1 determines whether or not the open / closed states of both hook switches 13a, 20a are the same (S14). If it is determined that they are the same (S14: YES), the CPU 1 The generation of the warning light is stopped (S15), and the process returns to S1. That is, when the handset 20 is replaced, both the hook switches 13a and 20a are turned on hook or off hook, and the generation of the warning sound and the warning light is stopped.
[0049]
In S14, when the open / close states of the hook switches 13a and 20a are different (S14: NO), the CPU 1 returns to S13 and continues to generate the warning sound and the warning light.
[0050]
If the signal from the first hook switch 13a is not detected in S2 (S2: NO), the CPU 1 determines that there is no power supply current from the external power supply and that there is a power failure, and executes the power failure process (S16). This routine ends. This power failure process is a process for controlling a call process or the like according to an open / close signal from the second hook switch 20a that operates based on the line current and a hook switch (not shown) of the telephone device 30. Since it is the same as the call processing operation, its detailed description is omitted.
[0051]
FIG. 4 is a time chart showing the correspondence between the opening / closing signals of the first and second hook switches 13a and 20a and the warning signal. The series of processing procedures will be described based on this time chart. In the normal operation state, that is, when both hook switches 13a and 20a are in the same state, the open / close signals from the first and second hook switches 13a and 20a are as shown by the solid lines from t1 to t2. Both have the same waveform signal. On the other hand, although the signal from the first hook switch 13a is at a low level after t2, the signal from the second hook switch 20a is high at t2 to t3 as shown by the broken line, even though the signal from the first hook switch 13a is at a low level after t2. In the case of the level, the warning signal output when the warning sound or the warning light is generated becomes the high level. In the period from t2 to t3 when the warning signal is at a high level, the generation of warning sound and warning light is continued. When the open / close signals of the first and second hook switches 13a and 20a are at a low level, they are on-hook (line open), and when they are high, they are off-hook (line close). Further, when the warning signal is at a low level, the processing operation related to the warning is not performed, and when the warning signal is at a high level, the warning operation is being executed.
[0052]
Therefore, according to the facsimile apparatus having the above-described configuration and operation, the first and second hook switches 13a and 20a provided in the first and second hook switches 13a and 20a are different from each other depending on how the handset 20 is placed on the apparatus body. There is. In such a case, an open / close signal from both hook switches 13a and 20a is detected, and it is determined by the CPU 1 that there is a difference in the open / close state. As a result, a warning sound is generated when the operations of both hook switches 13a and 20a differ. Or, since a warning light is generated, even if a problem occurs in the line connection status according to the open / close state of the two types of hook switches 13a and 20a, the user is alerted by emitting a warning sound or a warning light. it can.
[0053]
Specifically, if the handset 20 is not correctly placed on the apparatus body after the call is finished, even if the user thinks that the line has been disconnected, the warning sound or warning light Can prompt the user to reposition the handset 20, and then place the handset 20 on the main body of the apparatus accurately, so that the ringing tone from the other party cannot be received. Alternatively, it is possible to solve problems such as the case where the charged state may be sustained.
[0054]
Of the first and second hook switches 13a and 20a and the telephone device 30, the second hook switch 20a and the telephone device 30 output the open / close signal based on the line current of the communication line. Even when the first hook switch 13a cannot be used due to a power failure or the like, another hook switch operates normally, so that the connection with the public telephone line 21 during a power failure or the like can be guaranteed.
[0055]
Although the present embodiment is realized by a facsimile machine, it can also be applied to a telephone device that transmits and receives voice.
[0056]
Further, both hook switches 13a and 20a may operate with the power source current and the line current reversed.
[0057]
【The invention's effect】
As described above, according to the communication device of the first aspect of the present invention, depending on how the input / output terminal is placed on the device body, the open / close states of the first and second hook switches respectively attached to each other are mutually different. May be different. In such a case, the opening / closing signals from both hook switches are detected and it is determined that there is a difference in the opening / closing state, and as a result, a warning sound or warning light is generated when the operations of both hook switches are different. Even when a problem occurs in the line connection status according to the open / close state of the two types of hook switches, the user can be alerted by emitting a warning sound or warning light. Specifically, if the input / output terminal is not placed correctly with respect to the main unit after communication is completed, the warning sound or warning light may be emitted even if the user thinks that the line has been disconnected. Can prompt the user to reposition the input / output terminal, and then place the input / output terminal accurately on the main body of the device, so that the call signal from the other party cannot be received or is charged It is possible to solve problems such as being sustained.
[0058]
According to the communication device of the invention described in claim 2, in addition to the effect of the communication device according to claim 1, one of the first and second hook switches is a communication line. Since the open / close signal is output based on the current, even if the other hook switch cannot be used due to a power failure, etc., one hook switch operates normally. Can be guaranteed.
[0059]
[0060]
Claims 3 According to the communication apparatus of the invention described in claim 1, Or Claim 2 In addition to the effects of the communication apparatus described in (1), the present invention can be applied to a facsimile apparatus, and image data can be transmitted and received based on the facsimile communication function.
[0061]
And claims 4 According to the communication device of the invention described in claim 1, claims 1 to 3 In addition to the effects of the communication device described in any of the above, it can be applied to a facsimile device or a telephone device equipped with a handset, and can transmit and receive call voice based on the telephone function via the handset. .
[0062]
Claims 5 According to the communication device of the invention described in claim 1 Or claims 4 In addition to the effects of the communication device described in any one of the above, for example, it can be used in a usage form in which a telephone device is connected to the main body of the facsimile device.
[0063]
And claims 6 According to the storage medium of the invention described in (1), the operation of the communication device according to claim 1 can be realized by operating the CPU based on the stored program.
[Brief description of the drawings]
FIG. 1 is a circuit block diagram showing a circuit configuration of a facsimile apparatus as an example of a communication apparatus according to the present invention.
FIG. 2 is an external perspective view showing an outer periphery of the facsimile apparatus.
FIG. 3 is a flowchart showing a processing procedure according to the line connection status of the facsimile apparatus.
FIG. 4 is a time chart showing a correspondence relationship between opening / closing signals and warning signals of the first and second hook switches.
[Explanation of symbols]
1 CPU
2 NCU
3 RAM
4 Modem
5 ROM
6 EEPROM
7 Gate array
8 codec
9 DMAC
10 Audio codec
11 Reading unit
12 Recording section
13 Operation part
13a First hook switch
14 Display section
15 Pronunciation part
20 Handset
20a Second hook switch
21 Public telephone line
30 Telephone equipment

Claims (6)

First and second hook switches for opening and closing an electrical connection with the communication line are attached to each of the apparatus main body and the main body detachable input / output terminal connected to the communication line. A communication device comprising a notification means for emitting light,
An open / close state determination means for detecting an open / close signal from the first and second hook switches and determining whether there is a difference between the open / close states of the both hook switches;
A communication apparatus comprising: a warning notification control means for generating a warning sound or a warning light by the notification means when the opening / closing state determination means determines that the opening / closing states of the hook switches are different.   2. The communication apparatus according to claim 1, wherein one of the first and second hook switches outputs an open / close signal based on a line current of the communication line. The apparatus main body, a facsimile apparatus main body, the communication apparatus according to claim 1 or claim 2. The communication apparatus according to any one of claims 1 to 3 , wherein the main body detachable input / output terminal is a handset for inputting and outputting call voice. The apparatus main body is provided with line branching means for branching the communication line, and the main body detachable input / output terminal and various types of input / output terminals can be connected via the line branching means. ,
Output terminals of the various forms is a telephone apparatus having a handset, a communication device according to any one of claims 1 to 4. First and second hook switches for opening and closing an electrical connection with the communication line are attached to each of the apparatus main body and the main body detachable input / output terminal connected to the communication line. A storage medium storing a program for controlling a communication device having a notification means for emitting light,
An open / close state determination program for detecting open / close signals from the first and second hook switches and determining whether there is a difference between the open / close states of the both hook switches;
When it is determined based on the open / close state determination program that there is a difference between the open / close states of the hook switches, a program including a warning notification control program for generating a warning sound or warning light by the notification means is stored. A storage medium characterized by that.

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