JPH033974B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to electronic circuit devices, particularly electronic circuit devices including radios and recording/playback devices installed in passenger cars, for example, under special circumstances. The present invention relates to an electronic circuit device that can enter a normal operating state only when a password code matches when the power is turned on.

(Prior Art) Although the present invention is not limited thereto, there are cases where an electronic circuit device installed in a passenger car or the like is removed from the car and stolen. As a method of preventing such theft, there is a conventional method of mechanically locking the electronic circuit device on a dash board or the like. However, this method has drawbacks such as the complicated structure and high cost, and the fact that the dash board and the like can be destroyed and even stolen.

(Problem to be solved by the invention) As mentioned above, even if a conventional electronic circuit device is stolen, it will operate normally if power is supplied again, so there are limits to mechanical locking methods. It was hot.

An object of the present invention is to provide an electronic circuit device that solves this problem, by comparing a PIN code stored in advance in a storage means with a PIN code input by a code inputting means, and determining the PIN code. It is an object of the present invention to provide an electronic circuit device which operates normally only when the information matches, and which does not normally require inputting a PIN code, although this is required in case of theft.

(Means for Solving the Problems) In order to achieve the above object, an electronic circuit device of the present invention includes a detection means for detecting whether or not the electronic circuit device is removed from a mobile traveling device, etc.; normal operation state prohibition means for prohibiting the normal operation state of the electronic circuit device when removal is detected; storage means for storing a password code in advance; and code input means for inputting the password code. , means for collating the password code inputted by the code input means and the password read from the storage means; and when the verification means detects a match between the password codes, prohibition by the normal operation state prohibition means is performed. and means for canceling the processing.

(Function) By detecting whether the electronic circuit device has been removed or not and whether the password code matches, the electronic circuit device will not operate normally if it is stolen.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows the configuration of an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the processing mode of the embodiment of the control section shown in FIG. 1.

In FIG. 1, 1 is an antenna, 2 is a high frequency amplifier circuit, 3 is a mixer circuit, 4 is a voltage controlled oscillator in a PLL circuit and corresponds to a local oscillator, 5 is an intermediate frequency amplifier circuit, 6 is a detection circuit,
7 is a stereo separation circuit, 8 is an audio output prohibition circuit prepared in the present invention and corresponds to the driving state prohibition circuit according to the present invention, 9 is an output amplification circuit, 10 and 11 are speakers, 12, 13 are magnetic heads, 14 and 15 are equalization amplifier circuits, 16 is a control unit for controlling tuning of the PLL synthesizer type radio, and 17
is a low-pass filter that constitutes a PLL circuit, 1
8 is a prescaler which extracts a tuned frequency when receiving FM in the illustrated case; 19 is a control input section used for inputting a password code; 20 is a display driver for display; 21 is a display. 22 is a memory back-up power supply for securing the power supply for the memory for the password code etc. held in the control unit 16, and the vehicle +B power supply. represents a power source for a passenger car, etc.

Assuming that the audio output inhibiting circuit 8 is in the non-inhibiting state in a normal operating state, the broadcast waves from the antenna 1 are transmitted to the circuit elements 2, 3, 4, 5,
6, 7, 8 (non-inhibited state), 9, 10, and 11, and output as audio output by speakers 10 and 11. In addition, heads 12, 13, amplifiers 14, 15 are compatible with magnetic recording and reproducing devices.
The output from the audio output inhibit circuit 8, which is in the non-inhibited state, is outputted by the speakers 10 and 11.

Under normal operating conditions, it operates as described above, but in a set for Europe, for example, it is configured so that the FM tuning frequency when receiving FM is displayed as a six-digit number on the display 21. ing. That is, when the output frequency of the voltage controlled oscillator 4 is controlled by the control section 16, the frequency currently selected is picked up by the prescaler 18, and the control section 16 controls the driver 20. The tuning frequency is displayed numerically on the display 21.

In the case of the present invention, the pin code input means is not limited to this, and it goes without saying that other input means may be used, but focusing on the fact that the display 21 has a tuning frequency display function,
It is used to enter the PIN code mentioned above.

That is, when the electronic circuit device is installed, first set it to FM reception mode, select a specific tuning frequency on the display 21, and use the key operation from the control input section 19. Then, numerical information corresponding to the tuned frequency is stored in the control section 16. It should be noted that, for example, about 680 numbers can be given to the password code input using the numerical display of the tuning frequency, which can be considered to be a number that does not cause any problem in practical use.

As mentioned above, once the PIN code has been memorized, the numbers corresponding to the PIN code can be displayed on the display 21 when the power is turned on, for example, under special operating conditions as explained with reference to FIG.
The control unit 16 keeps the audio output prohibition circuit shown in FIG. 1 in the prohibited state unless the code is correctly verified against the previously stored password. For example, if the password is entered incorrectly within the range of 10 times, this prohibited state will be resolved if the password is entered correctly, but if the password is entered incorrectly more than 10 times, only a person with special authority can do so. Unless the reset circuit 23 activates a process known to the above, that is, a reset function by the reset circuit 23, the prohibited state will not be cleared.
Enters a state such as powering off.

FIG. 2 shows an embodiment of processing related to password input in the control section.

When the power is turned on, in this state, if the PIN code is not stored in the device as described above,
Proceed to the illustrated route A, and as described above, store the password code F ₀ in the form corresponding to the predetermined tuning frequency. At the time when the memory is stored, "YES" is displayed on the display 21, and the normal operating state is entered. In other words, it can be activated at will, whether for radio reception or recording playback. If the power is turned off and then turned on again in this state, the following will occur. That is, this time, the process proceeds along route B shown in FIG. 2, and it is checked whether or not the "vehicle +B power supply" shown in FIG. 1 has been cut off under some circumstances. That is, it is checked whether the electronic circuit device is being operated after being removed from the vehicle. Whether or not it has been removed is determined by the first
In response to energy from the illustrated backup power source 22, the control unit 16 uses a switch or the like to determine whether or not there is voltage at the illustrated INT and whether or not, for example, an electronic circuit device is installed at a predetermined equipment position on the passenger car. Memorize it and check it. If the "vehicle +B power supply" is not disconnected, the vehicle can proceed along the illustrated route B and enter a normal driving state.

However, if the "vehicle +B power supply" is disconnected, the operator may, for example, display a specific tuned frequency on the display 21 in the same way as above.
It becomes necessary to give a collation instruction from the control input section 19. That is, proceed to route C shown in FIG. Then enter the code F and the previous pin code
If F ₀ matches, the normal operating state is entered. However, if there is a mismatch, the electronic circuit device is allowed to re-enter 10 times, and if the input is still incorrect, the electronic circuit device is turned off or otherwise rendered unusable.

Note that memorizing the above-mentioned PIN code, determining that it is installed on the vehicle, verifying the PIN code, and generating control output for the driving state prohibition circuit can be easily performed by simply incorporating an extremely small processor. It is possible.

(Effects of the Invention) As described above, according to the present invention, it is possible to detect whether or not an electronic circuit device has been removed from a mobile traveling device, etc., and when it is detected that an electronic circuit device has been removed, it is stored in the storage means in advance. Since the electronic circuit device does not enter the normal operating state unless the same code as the stored password is entered through the control input means, even if it is stolen, it will not operate normally just by supplying power, thus preventing theft. It has a great effect. Furthermore, when installed in a vehicle, there is no need to enter a personal identification code each time, so it is not inconvenient to use. Furthermore, the structure is simpler and less costly than mechanical locking methods.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the processing mode of an embodiment of the control section shown in FIG. 1. In the figure, 8 represents an operating state prohibition circuit, 16 a control section, 19 a control input section, 21 a display, and 22 a memory backup power source.

Claims (1)

[Scope of Claims] 1. In an electronic circuit device that is used by being attached to a mobile traveling device, etc., which becomes capable of normal operation when the power is turned on, it is determined whether or not the electronic circuit device is removed from the mobile traveling device, etc. a detection means for detecting;
normal operation state prohibition means for prohibiting the normal operation state of the electronic circuit device when removal is detected by the detection means; a storage means for storing a password code in advance; and a storage means for inputting the password code. code input means; means for collating a pin code input by the code input means with a pin code read from the storage means; and when a match between the pin codes is detected by the collation means, the normal operating state is reached. 1. An electronic circuit device comprising: means for canceling prohibition processing by prohibition means. 2. The electronic circuit device according to claim 1, wherein the detection means for detecting the presence or absence of said removal is a cutoff detection means for detecting the presence or absence of cutoff of power input. 3. Claim 1, characterized in that a password code stored in advance in the storage means for verification can be set by the code input means.
The electronic circuit device described in Section 1. 4. The electronic circuit device according to claim 1, wherein the electronic circuit device is configured to be able to re-enter the code at least once if the verification means does not detect a match between the password codes. 5. The electronic circuit device according to claim 1, wherein the mobile traveling device is a vehicle, and the electronic circuit device is a vehicle-mounted electronic device.