JP2003319547A - Overcurrent detection control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an overcurrent detection control system capable of preventing failures, smoking, or firing at a plurality of members by shutting off power to a component if an overcurrent abnormality occurs at the component and forcedly turning off a power source, with a feeding path of a component comprising a CPU on an electronic circuit board of a computer device provided with an overcurrent detection circuit appropriate for the allowable current capacity of the component. <P>SOLUTION: A computer device 1 is provided with, as shown in Fig. 1, the overcurrent detection control system which comprises a power source part (power supply) 2, an electronic circuit board 3, an overcurrent detection circuit 4, and an electronic device 5, etc. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overcurrent detection control system, and more particularly to an overcurrent detection control system for controlling abnormal power supply to an electronic device including a CPU of a computer device.

[0002]

2. Description of the Related Art Conventionally, when an overcurrent abnormality or a short circuit abnormality occurs in a part, an overcurrent detection system shuts off the power supply to the part and also stops the operation of the power supply part to stop the operation of the parts. It is configured to prevent multiple failures, smoke, and fire. In addition, for short circuit protection or overcurrent protection in a computer device, generally, a power supply unit, which is a power supply source, detects an abnormal state of the power supply unit and forcibly stops power supply.
The technique of FF has been taken.

Japanese Patent Laid-Open No. 2001-352674 discloses that
In a power supply circuit to which a plurality of loads are connected, such as a disk array device, a technique has been disclosed that prevents other loads from collapsing due to an abnormality in a part of the loads. In this technique, in a power supply circuit including a converter device to which a plurality of loads are connected, an abnormality detecting unit for each of the plurality of loads and a power supply to the load when the abnormality detecting unit detects an abnormality. A power supply stop switch for stopping the power supply is provided.

Further, Japanese Patent Laid-Open No. 7-288930 discloses a power supply circuit in a magnetic disk device or the like,
A technology has been published that realizes low cost, high efficiency, and high reliability of the device by cutting off the overcurrent of the load circuit at high speed without a fuse and preventing the influence of voltage fluctuation on other load circuits. There is. In a power supply circuit that supplies power from a power supply circuit to a plurality of load circuits via separate power supply lines, each power supply line is capable of turning on / off the power supply line. , FET)
And an overcurrent detection resistor for detecting an overcurrent of the load circuit are connected, and when an overcurrent is detected based on the detection signal from the overcurrent detection resistor, the breaking element is turned off to A short-circuit protection control unit that cuts off the power supply line of the load circuit that has detected the current, a voltage monitoring circuit that monitors the voltage of the load circuit, and a control circuit that controls the load circuit are provided.

[0005]

However, the prior art has the following problems.

When a short circuit failure occurs in a device on the electronic circuit board, the overcurrent detection value of the power supply is several tens to several hundreds times the maximum current rating value of the target device. Before detecting a short-circuit state or an overcurrent state, a failure may occur in a plurality of members such as damage to other electric components, damage to connectors, and breaks in the board pattern. Specifically, in general, the power supply unit has an overcurrent detection function of stopping the output supply when an overcurrent abnormality or a short circuit abnormality of about 1.1 times the rated output current or more is detected. When an element failure occurs in the device and a short circuit abnormality occurs, the overcurrent detection value of the power supply unit is tens to hundreds of times the maximum current rating value of the electronic device. The short-circuited state could not be detected, the operation was continued, and not only the damage of the electronic device but also other electric parts, the damage of the connector of the power feeding path, the disconnection of the pattern, and the like could occur in multiple members. Especially CPU
Since the power supply capacity is much larger than the capacity of the (electronic device), it is not possible to detect a power supply short circuit due to a CPU short circuit abnormality.

Further, in a parallel power supply device using a hot-pluggable disk array device or the like as a load, when an abnormality occurs in a certain load, the supply to that load is stopped and another load is supplied. However, in the conventional technique of continuing to supply the above, the countermeasure against the member damage due to the load abnormality in the general computer device is insufficient. That is, when the load is the CPU, when an abnormality occurs in the CPU, only the power supply to the CPU is cut off and the power is continuously supplied to the other loads. In a difficult and extremely complicated and complicated computer circuit, there is a problem that the damage situation of the electronic circuit board or the members on the electronic circuit board may be deteriorated from the viewpoint of safety such as prevention of damage to plural members and prevention of burnout. there were.

The present invention has been made in view of the above problems, and an object of the present invention is to meet a current allowable capacity of a component in a power feeding path of a component including a CPU on an electronic circuit board in a computer device. A current detection circuit is provided, and when an overcurrent abnormality occurs in a certain component, the power supply to the relevant component is shut off and the power is forcibly turned off to prevent failure, smoking, or ignition of multiple components. The point is to provide an overcurrent detection control system.

[0009]

According to a first aspect of the present invention, there is provided an overcurrent detection control system in an electronic circuit board such as a computer device, which is provided on the electronic circuit board, or A plurality of electronic devices; a power supply unit that supplies power to the electronic devices; and an overcurrent detection circuit that is provided in a power supply path between the electronic device and the power supply unit. The first power-on signal from the computer device is fetched and sent to the power supply unit as a second power-on signal, and the power supply unit uses the second power-on signal to cause the electronic device on the electronic circuit board to be received. DC voltage is supplied to the overcurrent detection circuit, and the voltage of the DC power in the power supply path is out of a range of reference values set in advance corresponding to the maximum current rated value of each electronic device. When blocks the feed line to the electronic device in question is judged that short-circuit failure occurs, and consists in the overcurrent detection control system characterized by forcibly turns off the power supply unit. According to a second aspect of the present invention, in the overcurrent detection circuit, a latch circuit that inputs the first power-on signal and a voltage of the input DC power that falls outside the range of the reference value. In that case, a comparator that outputs an abnormality signal to the latch circuit as the occurrence of the short circuit abnormality and sets the latch circuit to ON,
A current-voltage conversion circuit that monitors the power supply path and sends out a voltage obtained by converting the DC power to the comparator for comparison, and input a disconnection signal from the latch circuit corresponding to the abnormal signal, When a semiconductor switch that cuts off power supply to the electronic device and the captured first power-on signal is sent to the power supply unit as the second power-on signal and the disconnection signal is input To the second
And a power-on circuit for forcibly turning off the power-on signal of 1., wherein the disconnection signal is reset to OFF when the first power-on signal is input in the latch circuit. It exists in the overcurrent detection control system described. The gist of the present invention according to claim 3 is that the overcurrent detection circuit has an I2C device for inputting the disconnection signal from the latch circuit, and the I2C device is software for managing an operating state of the computer device. Of the disconnection signal to the operating recording means, the recording means, as the log of the information of the disconnection signal, including information that can identify the electronic device and the time when the disconnection signal is transmitted. It records in the overcurrent detection control system of Claim 2 characterized by the above-mentioned. Claim 4
The gist of the present invention resides in the overcurrent detection control system according to any one of claims 1 to 3, wherein one of the electronic devices is a CPU of the computer device. A fifth aspect of the present invention is a method for controlling overcurrent detection in an electronic circuit board of a computer device or the like, wherein the power-on circuit takes in a first power-on signal from the computer device, A first step of sending a power-on signal to a power supply unit, and the power supply unit supplying direct-current power to one or a plurality of electronic devices on the electronic circuit board by the second power-on signal. And a second step, the second step comprising:
When the voltage of the DC power in the power supply path between the electronic device and the power supply unit is out of the range of the reference value preset corresponding to the maximum current rated value of each electronic device, a short circuit abnormality occurs. And a third step of shutting off the power supply path to the corresponding electronic device when it is determined that the short-circuit abnormality has occurred. The first step shuts off the second power-on signal. Then, there is a fourth step of forcibly turning off the power supply section. The gist of the present invention according to claim 6 is that in the first step, a step of monitoring the power supply path, sending a voltage obtained by converting the DC power for comparison to a comparator, and converting the comparator. Comparing whether the voltage is outside the range of the reference value, the third step, if there is a voltage drop of the converted voltage, and is outside the range of the reference value, A step of outputting an abnormal signal to the latch circuit as the occurrence of the short circuit abnormality and setting the latch circuit to ON; and a latch circuit corresponding to the abnormal signal so that the semiconductor switch cuts off the power supply to the electronic device. In the fourth step, the power-on circuit forcibly turns off the second power-on signal when the power-on circuit receives the disconnection signal from the latch circuit. Process Seen, the latch circuit, when inputting the first power-on signal, consists in the overcurrent detection control method according to claim 5, characterized in that resetting the disconnection signal to OFF. The gist of the present invention according to claim 7 is the third step, or
In the fourth step, the I2C device inputs the disconnection signal from the latch circuit, information for identifying the electronic device in a recording unit operating software that manages the operation state of the computer device, and the disconnection signal. 7. The overcurrent detection control method according to claim 6, further comprising the step of transmitting information including the time at which was transmitted and recording it as a log. The gist of the present invention according to claim 8 is:
The overcurrent detection control method according to any one of claims 5 to 7, wherein the CPU of the computer apparatus is applied to one of the electronic devices.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an outline of an overcurrent detection control system according to this embodiment.

As shown in FIG. 1, the overcurrent detection control system according to the present embodiment includes a power supply section (power supply) 2, an electronic circuit board 3, an overcurrent detection circuit 4, and an electronic device 5. And is provided in the computer device 1.

The power supply section 2 receives direct current power (voltage, voltage) on the electronic circuit board 3 by a power-on signal (first power-on signal) 10a and a power-on signal (second power-on signal) 10b from the computer apparatus 1. Output rated current) V1 is supplied. Here, as shown in FIG.
a is taken into the overcurrent detection circuit 4, and the power-on signal 10
It is sent to the power supply unit 2 as b.

The overcurrent detection circuit 4 monitors the power supply path 10c to the electronic device 5, and when the DC power V1 exceeds (is out of the range) the reference value Vr of the overcurrent detection circuit 4, the electronic device 5 is detected. The operation of cutting off the power supply to the power supply and immediately forcibly turning off the power supply unit 2 is executed.

In FIG. 1, the power supply unit 2 includes a power-on signal 10a and a power-on signal 1 from the computer device 1.
0b supplies the DC power V1 to the electronic circuit board 3. The power supply unit 2 has an overcurrent detection function of stopping the output supply when an overcurrent abnormality or a short circuit abnormality of about 1.1 times the rated output current V1 or more. Further in accordance with the present invention, the electronic circuit board 3 has a power supply line 10 to the electronic device 5.
c is monitored, and when an abnormal current is detected, the power-on signal 1
An overcurrent detection circuit 4 for forcibly turning off 0b is provided.

The overcurrent detection circuit 4 is composed of an electronic device 5
If a short circuit occurs due to a defective element or foreign matter, the abnormal state is detected at the moment when the maximum current rated value of the electronic device 5 is reached, the power supply to the electronic device 5 is cut off, and the power is supplied. The operation of forcibly turning off the unit 2 is executed.

Next, the configuration of the overcurrent detection circuit 4 will be described in detail.

FIG. 2 is a block diagram showing a configuration example of the overcurrent detection circuit 4 of FIG.

The overcurrent detection circuit 4 includes a current-voltage conversion circuit 21, a comparator 22, a latch circuit 23, and a semiconductor switch 2.
4 and a power-on circuit 25.

By setting the reference value Vr in the comparator 22 in correspondence with the maximum current rated value of the electronic device 5,
The comparator 22 detects a voltage drop at the input. When a short circuit abnormality occurs in the electronic device 5, the comparator 22 outputs an abnormality signal 10e to the latch circuit 23, and the latch circuit 2
Set 3. The output of the latch circuit 23 to which the abnormal signal 10e is input is input to the semiconductor switch 24 and the power-on circuit 25 as the disconnection signal 10d.

The semiconductor switch 24 is turned off by the disconnection signal 10d, and the power supply to the electronic device 5 is cut off.

The power-on circuit 25 outputs the power-on signal 1
0a and disconnection signal 10d, and one output of power-on signal 10b.
The power-on signal 10b responds only by a, but when the disconnection signal 10d is raised, the power-on signal 10b
It suffices to formulate the logic so that b is forced off. The power-on signal 10a resets the latch circuit 23, and resets the power-on signal 10d to reset the disconnection signal 10d.

Although the configuration of the embodiment has been described in detail above, the current-voltage conversion circuit 21 of FIG. 2 uses, for example, a resistor in the power supply path 10c and sends the voltage drop to the comparator 22. The latch circuit 23 is well known by those skilled in the art and has no direct relation to the present invention, and therefore detailed description thereof will be omitted.

Next, the flow of operation in the overcurrent detection control system will be described.

FIG. 3 is a timing diagram showing the movement of the signals in FIG.

First, the normal activation of the computer device 1 will be described with reference to FIG. The power-on signal 10a is taken into the power-on circuit 25, but since the disconnection signal 10d has not risen, it is output as it is as the power-on signal 10b. The power-on signal 10b is a signal for starting the power supply unit 2, and supplies the electronic circuit board 3 with the DC power V1. The DC power V1 is supplied to the electronic device 5 and the like, and the computer device 1 is activated.

FIG. 4 is a timing chart for comparison with signal movement when the overcurrent detection circuit 4 of FIG. 1 is used.

FIG. 5 is a timing chart showing the movement of signals when the overcurrent detection circuit 4 of FIG. 1 is used.

The function of the overcurrent detection circuit 4 will be described with reference to FIGS. 4 and 5.

First, with reference to FIG. 4, description will be given of a case where the overcurrent detection circuit 4 is not provided when an overcurrent abnormality occurs in the electronic device 5.

The voltage V1 drops to the voltage V2 by the amount of the abnormal current drawn in the electronic device 5. However, the power supply unit 2
Has not reached the point of detecting the overcurrent abnormality,
The unstable state of overcurrent abnormality continues. This period La
In addition, the damage to the electric parts around the electronic device 5, the connector of the power feeding system, the pattern, and the like will also occur. When the voltage V1 drops to the overcurrent detection point Vs of the power supply unit 2 due to damage to other components, the power supply shuts down, but when the abnormal factor is removed due to a pattern break or the like during the unstable period, The voltage V1 is restored.

Next, the case where the overcurrent detection circuit 4 is provided when an overcurrent fault occurs in the electronic device 5 will be described with reference to FIG.

Although the voltage V1 drops to the voltage V2 by the amount of the abnormal current drawn in the electronic device 5, the reference value Vr of the overcurrent detection circuit is set to the maximum current rated value of the electronic device 5, so that the voltage The comparator 22 sends the abnormal signal 10e to the latch circuit 23 at the Vr voltage before reaching V2.
The output of the latch circuit 23 turns off the semiconductor switch 24 as a disconnection signal 10d, and the abnormal signal 10e is released. The disconnection signal 10d is also sent to the power-on circuit 25, and when the disconnection signal 10d rises (is ON), the power-on signal 10b is forced off. The power-on signal 10a resets the latch circuit 23, and the power-off signal 10d resets (turns off) the power-on signal 10d again.

FIG. 6 is a block diagram showing another configuration example of the overcurrent detection circuit 4 of FIG.

Referring to FIG. 6, I2 is mounted on the electronic circuit board 3.
A C device 30 is provided. The I2C device 30 inputs the disconnection signal 10d and sends the information of the disconnection signal 10d to the recording means such as software for managing the state of the computer device 1. Therefore, by collecting the log, the electronic circuit board at the time of maintenance replacement. It is possible to easily discriminate which part on the above 3 is the abnormality. The log includes information (electronic device ID) that can identify the electronic device 5 that has caused the disconnection signal 10d and the time when the corresponding information is sent. Descriptions of other components are the same as those in FIG. 2 and are omitted.

Although the overcurrent detection of the electronic device 5 has been described above, there is no limitation on the target parts and members. When the power supply unit 2 has multiple outputs, the overcurrent detection circuit 4 described above can be provided for each output power, and there is no particular limitation on the number of overcurrent detection circuits 4.

Since the overcurrent detection control system according to the embodiment is configured as described above, it has the following effects.

In the short-circuit protection or overcurrent protection of a computer device in the prior art, generally, a power supply unit, which is a power supply source, detects an abnormal state of the power supply unit and performs a protection operation of forcibly turning off the power supply. When a short circuit failure occurs in a device on the board, the overcurrent detection value of the power supply is several tens to several hundred times the maximum current rating of the target device, so the power supply is in a short circuit or overcurrent condition. Before the current state is detected, a failure may occur in a plurality of members such as damage to other electric components, damage to connectors, and pattern breaks on the board. However, the overcurrent detection circuit 4 is provided on the electronic circuit board 3 of the computer device 1 in the present embodiment, and when the overcurrent abnormality occurs in the target electronic device 5, the power supply to the electronic device 5 is cut off, The power supply unit 2 is forcibly turned off immediately, and failure of a plurality of members can be prevented. That is, conventionally, when a failure occurs in an electronic device or the like and an overcurrent flows in the power feeding path, not only damage to the electronic device itself but also damage to other electric components, damage to a connector of the power feeding path, disconnection of a plurality of members such as pattern disconnection, etc. In some cases, a failure may occur, and when the power capacity of the power supply unit is large, the power supply continued to operate without the overcurrent protection function of the power supply. However, in the present embodiment, the electronic circuit board 3 has Since the overcurrent detection circuit 4 is provided and the power supply to the electronic device 5 is shut off when an abnormality is detected, and the power supply unit 2 is immediately turned off forcibly, failure of other plural members in the electronic circuit board 3 is prevented, and smoke and ignition are generated. It is possible to prevent such accidents.

Further, by applying the CPU of the computer device 1 to the electronic device 5, the power supply is shut down promptly in the event of a power supply abnormality in the CPU, and a computer system according to the prior art due to software defects or CPU malfunctions. It is possible to perform processing different from the abnormal operation (hangup state, etc.) in.

Further, the latch circuit 23 and the power-on circuit 2
By providing a delay circuit between the latch circuit 2 and
It is also possible to input the disconnection signal 10d sent from the device 3 to the power-on circuit 25 via the delay circuit, shut off the power supply to the corresponding electronic device 5, and forcibly turn off the power supply unit 2 after a time lag of a predetermined time. it can. The latch circuit 2
The combination of the set (ON state) and the reset (OFF state) of No. 3 can be set (OFF state) and reset (ON state).

In the present embodiment, the present invention is not limited to this, and can be applied to an overcurrent detection control system suitable for applying the present invention.

Further, the number, position, shape, etc. of the above-mentioned constituent members are not limited to those in the above-mentioned embodiment, and the number, position, shape, etc. suitable for carrying out the present invention can be adopted.

In each figure, the same components are designated by the same reference numerals.

[0044]

Since the present invention is configured as described above, it has the following effects.

An overcurrent detection circuit commensurate with the capacity is provided in the power supply path of the electronic device including the CPU on the electronic circuit board, and when abnormality is detected in the electronic device, the power supply to the corresponding electronic device is cut off and the power supply is immediately turned off forcibly. Therefore, it is possible to prevent failure of a plurality of members and prevent accidents such as smoking and ignition. Further, by freely setting the reference value of the comparator, it is possible to freely set the portion for current monitoring. Furthermore, since the power supply section does not require any special specifications, the existing power supply can be used.

Further, by inputting the disconnection signal from the latch circuit,
By providing a device on the electronic circuit board that can send the information of the disconnection signal to the software that manages the state of the computer device, it is possible to analyze the collected logs and easily identify the abnormal part on the electronic circuit board during maintenance replacement. .

Further, in case of power supply abnormality in the CPU on the electronic circuit board, the computer system is not hung up, and the power can be shut off promptly to perform the next work.

[Brief description of drawings]

FIG. 1 is a block diagram showing an outline of an overcurrent detection control system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration example of an overcurrent detection circuit in FIG.

FIG. 3 is a diagram showing timing of signals in FIG.

FIG. 4 is a timing diagram compared with signal movement when the overcurrent detection circuit of FIG. 1 is used.

5 is a timing chart showing the movement of signals when the overcurrent detection circuit of FIG. 1 is used.

FIG. 6 is a block diagram showing another configuration example of the overcurrent detection circuit of FIG.

[Explanation of symbols]

1 computer equipment 2 Power supply section (power supply) 3 Electronic circuit board 4 Overcurrent detection circuit 5 Electronic devices 10a Power-on signal (first power-on signal) 10b Power-on signal (second power-on signal) 10c power supply line 10d disconnection signal 10e Abnormal signal 21 Current-voltage conversion circuit 22 Comparator 23 Latch circuit 24 Semiconductor switch 25 Power-on circuit 30 I2C device La period V1 DC power (voltage, output rated current) V2 voltage Vr reference value Vs Overcurrent detection point

Claims (8)

[Claims] 1. An overcurrent detection control system for an electronic circuit board such as a computer device, comprising: one or a plurality of electronic devices provided on the electronic circuit board; and a power supply section for supplying power to the electronic device. And an overcurrent detection circuit provided in a power supply path between the electronic device and the power supply section, the overcurrent detection circuit being a first circuit from the computer device.
Of the power on signal and sends it to the power supply section as a second power on signal, and the power supply section supplies DC power to the electronic device on the electronic circuit board by the second power on signal. The overcurrent detection circuit, when the voltage of the DC power in the power supply path is out of the range of the reference value preset corresponding to the maximum current rated value of each electronic device, the short circuit abnormality has occurred. An overcurrent detection control system, which judges and shuts off a power supply path to the corresponding electronic device and forcibly turns off the power supply unit. 2. The overcurrent detection circuit comprises a latch circuit for inputting the first power-on signal, and the short-circuit abnormality when the voltage of the input DC power falls outside the range of the reference value. Is generated, an abnormal signal is output to the latch circuit to turn on the latch circuit.
A current-voltage conversion circuit that monitors the power supply path and sends out a voltage obtained by converting the DC power for comparison to the comparator; and a latch circuit corresponding to the abnormal signal. And a semiconductor switch that cuts off power supply to the electronic device, and sends the captured first power-on signal to the power supply unit as the second power-on signal to disconnect the power. A power-on circuit for forcibly turning off the second power-on signal when a signal is being input, wherein the disconnection signal is reset to off when the first power-on signal is input in the latch circuit. The overcurrent detection control system according to claim 1, wherein: 3. The overcurrent detection circuit has an I2C device for inputting the disconnection signal from the latch circuit, and the I2C device is a recording unit operated by software that manages an operation state of the computer apparatus. The information of the disconnection signal is transmitted, and the recording unit records, as the log, the information including the information that can identify the electronic device and the time when the disconnection signal is transmitted, about the information of the disconnection signal. The overcurrent detection control system according to claim 2. 4. The overcurrent detection control system according to claim 1, wherein one of the electronic devices is a CPU of the computer device. 5. A method for controlling overcurrent detection in an electronic circuit board of a computer device or the like, wherein a power-on circuit takes in a first power-on signal from the computer device and uses it as a second power-on signal as a power supply section. And a second step in which the power supply section supplies DC power to one or a plurality of electronic devices on the electronic circuit board by the second power-on signal. In the second step, the voltage of the DC power in the power supply path between the electronic device and the power supply unit is a reference value set in advance corresponding to the maximum current rated value for each electronic device. When it is out of the range, the method includes a third step of determining that a short circuit abnormality has occurred and shutting off a power supply path to the corresponding electronic device. The first step includes a step of determining that the short circuit abnormality has occurred. The second shut off the power-on signal, the overcurrent detection control method characterized by comprising a fourth step of forced off the power supply unit. 6. The first step is a step of monitoring the power supply path, sending a voltage obtained by converting the DC power for comparison to a comparator, and the voltage converted by the comparator being the reference voltage. And a step of comparing whether or not the value is out of a range of values, and the third step includes the occurrence of the short-circuit abnormality when there is a voltage drop of the converted voltage and is out of the range of the reference value. Outputting an abnormal signal to the latch circuit and setting the latch circuit to ON; and inputting a disconnection signal from the latch circuit corresponding to the abnormal signal in order for a semiconductor switch to cut off power supply to the electronic device. And a step of forcibly turning off the second power-on signal when the power-on circuit receives the disconnection signal from the latch circuit. The overcurrent detection control method according to claim 5, wherein the circuit resets the disconnection signal to OFF when the first power-on signal is input. 7. In the third step or the fourth step, the I2C device receives the disconnection signal from the latch circuit and operates by software that manages the operation state of the computer device. 7. The overcurrent detection control method according to claim 6, further comprising the step of transmitting information including information that can identify the electronic device and a time when the disconnection signal is transmitted to the means and record the information as a log. 8. The overcurrent detection control method according to claim 5, wherein the CPU of the computer device is applied to one of the electronic devices.