JP2021089589A - Portable terminal - Google Patents

Abstract

To easily recognize an unauthorized access from an external memory connector and prevent information leakage without using mechanical means.SOLUTION: A portable terminal having an external memory connector includes: a sensor unit configured to detect the opening and closing of an external memory connector cover of the external memory connector; a sensor unit configured to detect a specific state to distinguish between normal and unauthorized accesses; a storage unit configured to store the specific state and confidential information corresponding to the normal access; discrimination means for discriminating between normal and unauthorized accesses; and a control unit configured to execute processing based on a discrimination result of the discrimination means.SELECTED DRAWING: Figure 3

Description

The present invention relates to a mobile terminal for business use, and particularly to prevent leakage of confidential information in a portable mobile terminal.

Conventionally, in commercial mobile terminals that handle confidential information, in order to prevent the terminal body from being illegally destroyed or disassembled and unauthorized access to the confidential information stored in the memory in the internal electronic circuit, it is roughly divided. We have taken two preventive measures.

As a first method, when unauthorized destruction or dismantling of a terminal is mechanically, optically, or magnetically detected by a spring, a phototransistor, or a Hall element mounted on a printed circuit board in the terminal, it is confidential. It erases the data in the memory that stores the information (for example, Patent Document 1).

The second method is to provide a special mechanism in the terminal itself to prevent unauthorized access, thereby preventing the terminal from being easily destroyed or disassembled (for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 7-219853 Japanese Patent Application No. 2004-222061

In the second method, unauthorized access to the internal memory may be prevented by fastening the connector cover for accessing the external memory connector such as USB or SD with a special screw.

The above-mentioned special screw refers to a screw having a shape that cannot be turned by a general-purpose screwdriver generally used at home, such as a Phillips screwdriver or a flat-blade screwdriver.

In the above-mentioned confidential information leakage prevention method using special screws, if a malicious third party possesses a special tool that can open and close the special screws, or the external connector itself is directly destroyed. In some cases, unauthorized access cannot be blocked.

In addition, since the external memory connector may be used by the administrator of the mobile terminal for business use in the previous term when downloading business data, if the connector cover for accessing the above connector is fastened with a special screw, a special tool is held. If it is not done, it cannot be opened and closed, and of course, opening and closing of special screws is always involved at the time of access, which leads to a decrease in work efficiency.

Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a mobile terminal capable of detecting unauthorized access without using a special screw or the like.

In view of the above, the mobile terminal of the present invention is
In a mobile terminal having an external memory connector
A sensor unit that detects the opening and closing of the external memory connector cover of the external memory connector, and
A sensor unit that detects a specific state to distinguish between normal and unauthorized access,
A storage unit that stores the specific state and confidential information corresponding to normal access,
It is characterized by including a discriminating means for discriminating normal / unauthorized access and a control unit for executing processing based on the discriminating result of the discriminating means.

According to the present invention, unauthorized access to the storage unit from an external memory connector such as USB or SD can be detected to improve security.

The block diagram which shows the structure of one Example of this invention. A circuit diagram of an embodiment of the present invention. The flowchart which shows the unauthorized access detection method in one Example of this invention. The block diagram in another embodiment of this invention.

(Example 1)
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention. In the figure, the printed wiring board 2 mounted inside the terminal device 1 of the mobile terminal according to the present embodiment has a hall sensor 5 which is a sensor unit for magnetically detecting the opening and closing of the external memory connector cover 3. It is installed.

The hall sensor 5 is mounted near the external interface portion 6 on the printed wiring board 2, detects a change in the magnetic field of the magnet 4 installed on the external memory connector cover 3, converts the change in the magnetic field into an electric signal, and outputs the change.

The High / Low binary signal output from the Hall sensor 5 is notified to the control unit 7, and the storage unit 8 stores in advance the detection / non-detection correspondence according to the output binary signal. Therefore, it is possible to determine that the external memory connector cover 3 has been opened and closed.

The input unit 9 is arranged at an arbitrary position of the terminal device 1 and notifies the control unit 7 of an electric signal according to the input contents. As a matter of course, it has a power supply for supplying power to various elements such as the control unit 7, the input unit 9, and the hall sensor 5, and is also provided with a power supply SW for turning on / off the power supply.

The storage unit 8 stores in advance a normal access pattern input when the administrator opens the external memory connector cover 3, and controls when the Hall sensor 5 detects that the external memory connector cover 3 has been opened. The unit 7 functions as a specific state detection unit, and by determining whether or not a normal access pattern has been formed, it is possible to detect normal access / unauthorized access.

Here, when a mobile terminal having no input unit 9 is used, or when the input unit 9 cannot be used for some reason, the above function can be replaced by using the gyro sensor 11 as follows. Become.

The storage unit 8 stores in advance the orientation (sideways, upside down, etc.) of the terminal device 1 when the administrator opens the external memory connector cover 3, and detects that the external memory connector cover 3 has been opened by the hall sensor 5. At that time, it is possible to detect normal access / unauthorized access by determining the orientation of the terminal device 1 by the gyro sensor 11.

FIG. 2 is an example of a circuit diagram configured to prevent unauthorized access.

Here, the condition of normal access is set to "open the external memory connector cover 3 while the terminal device 1 is in a specific state", and FIG. 2 will be described. It should be noted that the term "in a specific state" includes inputting a specific input to the input unit 9, which will be described in the following description.

The Hall sensor 5 normally outputs a Low level electric signal when the external memory connector cover 3 is closed, but when it detects that the external memory connector cover 3 is opened, it outputs a High level electric signal. Output. There is also a Hall sensor IC whose logic is opposite, but in that case, the logic here does not necessarily have to be so because the logic may be matched in the subsequent circuits.

When a specific input is made, the input unit 9 outputs a high level electric signal like the hall sensor 5. As with the above, this logic does not necessarily have to be, but is an example.

Here, the condition for normal access is "in a specific state (while performing a specific input to the input unit 9)", but when considering actual use, the external memory connector cover 3 is used to use the external memory. It is not easy to continue to input a specific input to the input unit 9 while opening. Therefore, the logic circuit 10 makes it possible to maintain the signal level when a specific input is made even when the hand is separated from the input unit 9.

The electric signal output from the hall sensor 5 and the input unit 9 is calculated by the AND circuit 12, and the AND circuit 12 also outputs the high level electric signal only when both signals are output with a high level electric signal. To do.

The switch circuit 13 generates an output corresponding to ON / OFF control of the external memory power supply from the electric signal output by the AND circuit 12. As a result, when High is output from the AND circuit 12, that is, the Hall sensor 5 detects the opening of the external memory connector cover 3, and a specific input is made to the input unit 9. Sometimes it is possible to limit.

Further, when it is determined by the Hall sensor 5 that the external memory connector cover 3 has been opened and the software detects that the output of the AND circuit 12 is Low, it is determined that the access is unauthorized, and the control unit 7 determines that the access is unauthorized. Executes the confidential information deletion process in the storage unit 8.

As described above, in this embodiment, the circuit configuration is such that the AND circuit 12 outputs High only when the outputs of the Hall sensor 5 and the input unit 9 are High, that is, the output of the input unit 9 is High. By configuring the AND circuit 12 to output High when the external memory connector cover 3 is opened in this state, unauthorized access is detected, but the present invention is not limited to this. For example, when it is detected on the software that the outputs of the input unit 9 and the hall sensor 5 are both High, the power may be supplied to the external memory power supply.

When detecting unauthorized access even when the terminal device 1 is in the power-off state, it is sufficient to supply power only to the circuit configurations necessary for the above-mentioned unauthorized access detection process such as the hall sensor 5 and the input unit 9.

Further, the present invention can be suitably used in a terminal having a battery built in the main body, but in a terminal that operates by being supplied with AC power even when the battery capacity is insufficient or the battery is removed. Is applicable.

Hereinafter, an operation flowchart relating to the unauthorized access detection process in this embodiment will be described with reference to FIG. In this operation flowchart, an example of controlling to supply power to the external memory power supply when it is detected on the software that the outputs of the input unit 9 and the hall sensor 5 are both High will be described.

In the terminal device 1, the power supply of the external memory is turned off in the normal state (S1).

Here, the Hall sensor 5 detects whether or not the external memory connector cover 3 has been opened (S2). If not detected, the external memory power supply remains OFF.

When it is detected that the external memory connector cover 3 has been opened, the control unit 7 determines whether or not there is a specific input or whether or not it is in a specific state (S3).

When it is detected that a specific input is made or a specific state is detected, the AND circuit described with reference to FIG. 2 becomes High, the switch circuit 13 turns ON, and an external memory power supply is supplied (S4). By doing so, access to the external memory becomes possible (S5).

On the other hand, in S3, when the specific input or the specific state cannot be detected, the control unit 7 can select whether or not to delete the confidential information of the storage unit 8 (S6).

In S6, the user may be inquired whether or not to delete the confidential information by displaying a dialog on a display unit (not shown) provided in the terminal device 1, or a preset setting may be made. It may be configured to follow the operation. In any case, when executing the confidential information deletion process, the process proceeds to S7, the confidential information is deleted, and the process ends when the process is completed.

When the confidential information deletion process is not performed, the external memory power supply is not turned on and remains in the OFF state (S8), so that it is impossible to access the external memory (S9).

The gyro sensor 11 makes it possible to detect the orientation of the terminal device 1. If the terminal device 1 does not have an input unit, or if the input unit cannot be used for some reason, a specific orientation (upside down, upside down,) by the gyro sensor 11 is used instead of the specific input from the input unit. By detecting (horizontal orientation, etc.), it is possible to substitute for a specific input.

The conversion circuit 14 outputs a High / Low binary signal depending on whether or not the orientation of the terminal device 1 detected by the gyro sensor 11 is a specific orientation.

(Example 2)
Hereinafter, other examples will be described. This embodiment relates to a portable thermal printer as an example of the mobile terminal in the above embodiment, and relates to its print control.

Thermal printers are used for various purposes such as issuing statements at retail stores and issuing tickets for transportation. A thermal printer prints by applying heat from a print head to thermal paper (a special paper whose color changes when heat is applied). By generally using a stepping motor to convey the paper, it is possible to feed out fine paper according to the printing speed. Since it can be made smaller and lighter than other printers, it is widely used in mobile electronic devices.

Mobile electronic devices equipped with thermal printers have various uses, but because they can be carried around, they are often used around service users who use these electronic devices.

Thermal printers may be noisy when printing. This is due to the sound generated when the head and the paper are peeled off after the print head heats the thermal paper.

When printing, the head and thermal paper are attracted to each other, and the head applies heat to the printed portion. After printing on the thermal paper, the head cools the printed area. This is to prevent bleeding of the print due to residual heat, which occurs when the paper is conveyed while the print head is still hot. However, if this cooling time is long, the print head and the thermal paper stick to each other, and when the paper is peeled off, a peeling sound such as piercing the paper with a crackle and a needle is generated.

This sound is related to print speed and print quality. If the printing speed is high, the paper is conveyed before the head cools, so there is little sticking and the sound is quiet, but printing bleeding is likely to occur. On the contrary, when the printing speed is slowed down, there is little bleeding, but since the cooling time is long, the head and the paper tend to stick to each other, and peeling noise is likely to occur. Further, since it is related to the cooling time of the print head, peeling noise is likely to be generated when the outside air temperature is low, and conversely, peeling noise is unlikely to be generated when the outside air temperature is high.

Therefore, as a conventional technology, it is possible to appropriately control the generated sound according to the surrounding sound, and it is possible to satisfy both the convenience of the user such as prevention of inconvenience to the surroundings and demand for high-speed printing. Is provided. According to Patent No. 6150216, the CPU of the printer device collects ambient sound from the sound collecting unit to specify its characteristics, and also specifies the characteristics of the operating sound of the printer mechanism unit, and the characteristics and operation of the ambient sound. It is disclosed that the characteristics of sounds are compared and the operating state of the printer mechanism unit is controlled based on the comparison result. In this case, the operating state of the printer mechanism is controlled so that the characteristics of the ambient sound and the characteristics of the operating sound are similar.

In this conventional technology, the sound generated from the electronic device is controlled according to the ambient sound, whereas in this embodiment, the electronic device is used by discriminating the atmospheric pressure and the brightness in addition to the ambient sound. It is a method to determine the environment to be used and control the sound generated from the electronic device. Specifically, it controls whether or not the electronic device is used in an aircraft and the sound generated by the usage environment.

In the electronic device according to the present embodiment, first, at the start of printing control by the printing unit 22, ambient sound is collected from the sound collecting unit 27, and the control unit 21 specifies the loudness and characteristics of the sound. When the control unit 21 determines that the ambient sound pressure level is equal to or less than the threshold value stored in the storage unit 24 in advance, the operating sound of the printing unit 22 is prevented from becoming louder than a certain value with respect to the ambient sound pressure level. The printing unit 22 is controlled by a printing sound reduction operation. Specifically, the transport speed of the printing paper in the printing control is increased to suppress the sticking of the paper to the print head and reduce the peeling sound.

On the contrary, even if it is determined that the ambient sound pressure level is above a certain level, the atmospheric pressure measuring unit 26 measures the atmospheric pressure in the usage environment in order to determine whether or not the vehicle is inside the aircraft. Further, the illuminance measuring unit 25 determines the ambient brightness (outdoor: 10,000 to 100,000 lpx, under fluorescent light (indoor): 500 lpx, nighttime: 100 lpx or less).

If the sound pressure level is above a certain value, the result of the atmospheric pressure measuring unit 26 is below the standard atmospheric pressure (1013 hpa), and the surrounding brightness is bright, it is inside the aircraft, but the lights inside the aircraft are lit. It is judged that the state is in the state, and the control in the printing sound reduction operation is not performed. On the other hand, if the sound pressure level is above a certain value, the result of the atmospheric pressure measuring unit 26 is below the standard atmospheric pressure (1013 hpa), and the ambient brightness is dark (for example, 100 lpx or less), it is in the aircraft. , It is determined that the lighting in the machine is off, and print control is performed by the print sound reduction operation.

1 Terminal device 2 Printed wiring board 3 External memory connector cover 4 Magnet 5 Hall sensor 6 External interface unit 7 Control unit 8 Storage unit 9 Input unit 10 Logic circuit 11 Gyro sensor 12 AND circuit 13 Switch circuit 14 Conversion circuit

Claims (4)

In a mobile terminal having an external memory connector
A sensor unit that detects the opening and closing of the external memory connector cover of the external memory connector, and
A specific state detection unit that detects a specific state for determining normal / unauthorized access,
A storage unit that stores the specific state and confidential information corresponding to normal access,
It is characterized by including a discriminating means for discriminating normal / unauthorized access based on whether or not the mobile terminal is in the specific state, and a control unit for executing processing based on the discriminating result of the discriminating means. Mobile terminal. The mobile terminal according to claim 1, wherein the sensor unit is a hall sensor that magnetically detects the opening and closing of the external memory connector cover. It is provided with an input unit provided in the mobile terminal.
The specific state is a state in which a specific input is made to the input unit.
When the external memory connector cover is opened and closed, the discriminating means normally connects the external memory connector to the external memory connector depending on whether or not the specific state detecting unit detects the specific input stored in the storage unit. / The mobile terminal according to claim 2, characterized in that unauthorized access is determined. The control unit
The mobile terminal according to any one of claims 1 to 3, wherein the confidential information is deleted when the determination result of the determination means is unauthorized access.

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