JPH0653846A - Electronic circuit device - Google Patents

Abstract

PURPOSE:To require the input of a password code only when it is stolen and to eliminate the necessity of its input at normal time by collating a required and stored password code with a password code inputted from a code input means, and resetting inhibition processing only when both codes coincide with each other. CONSTITUTION:When the detachment of an electronic circuit device from a vehicle is detected by the interruption of power supply to a control part 16, the control part 16 inhibits the normal operation state of the device. One of plural password codes inputted to a control input part 19 is set up and collated with a password code stored in a storage part of the control part 16, and when both codes coincide with each other, inhibition processing can be reset.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit device, and more particularly to an electronic circuit device including a radio and a recording / reproducing device mounted on a passenger car, for example. The present invention relates to an electronic circuit device capable of shifting to a normal operating state only when they match.

[0002]

BACKGROUND OF THE INVENTION Although the present invention is not limited thereto, an electronic circuit device mounted on a passenger car or the like may be removed from the passenger car and stolen. As a method of preventing such theft, conventionally, there is a method of mechanically locking an electronic circuit device on a dashboard or the like. However, this method is complicated and costly.
There are drawbacks such as the dashboard being destroyed and then stolen.

[0003]

However, in such a conventional electronic circuit device, even if the electronic circuit device is stolen, it operates normally when the power is supplied again. There was a limit.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an electronic circuit device that solves this problem, in which a desired personal identification code can be set, and the desired personal identification code stored in the storage means and the code input means can be used. It is possible to cancel the prohibition process only by matching the input security code and if the security code matches, and to provide an electronic circuit device that does not normally need to input the security code if it is stolen. It is in.

[0005]

According to the present invention, there is provided an electronic circuit device having a built-in microprocessor which is mounted on a vehicle and can be operated normally when the power is turned on. Detecting the presence or absence of removal from the vehicle by the presence or absence of interruption of power input to the microprocessor, and the microprocessor when the detection means detects the removal. Normal operation state prohibiting means controlled by the processor to prohibit the normal operation state in the electronic circuit device, storage means capable of storing a personal identification code, code input means for inputting a personal identification code, and input by the code input means The security code of the microprocessor for collating the security code read with the security code read from the storage means. Means, a means for canceling the prohibition process by the normal operation state prohibiting means when the coincidence of the secret code is detected by the collating means, and one secret code selected from a plurality of secret codes by the code input means. This is achieved by means for storing the secret code in the storage means and then shifting to the normal operation state.

[0006]

According to the above construction, when the detection means for detecting whether or not the electronic circuit device is detached from the vehicle based on whether or not the power input to the microprocessor is interrupted is detected, the microprocessor is detected. The normal operation state in the electronic circuit device is prohibited, and the secret code is stored in the storage means by selecting and setting one secret code from a plurality of secret codes input by the input means and the code input means. The prohibition process can be canceled when the recitation code is collated and the coincidence of the recitation code is detected. Therefore, a desired personal identification code can be set, the desired personal identification code stored in the storage means and the personal identification code input by the code input means are collated, and the prohibition process can be released only when the personal identification codes match, Input of the secret code is necessary when it is stolen, but usually it is not necessary to input it.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 a processing mode of an embodiment of the control unit shown in FIG. 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 corresponding to a local oscillator in a PLL circuit, 5 is an intermediate frequency amplifier circuit, 6 is a detection circuit, 7 Is a separation circuit for stereo, 8 is an audio output prohibiting circuit prepared in the present invention and corresponds to the normal operation state prohibiting means in the present invention, 9 is an output amplifying circuit, 10 and 11 are speakers respectively, 1
Reference numerals 2 and 13 are magnetic heads, 14 and 15 are equalizing and amplifying circuits, 16 is a control unit for performing tuning control of a PLL synthesizer radio, 17 is a low-pass filter that constitutes the PLL circuit, and 18 In the figure, is a prescaler for extracting the tuning frequency at the time of FM reception, 19 is a control input section used for inputting a personal identification code, 20 is a display driver for display, and 21 is a display. So, for example, F
The M tuning frequency is displayed numerically, 22 is a memory backup power supply for securing the power supply of the memory for the secret code stored in the control unit 16, and the vehicle + B power supply is for a passenger car or the like. Represents a power supply.

Assuming that the audio output inhibiting circuit 8 is in the non-inhibiting state under the normal operating condition, the broadcast wave from the antenna 1 is generated by the circuit elements 2, 3, 4, 5, 6, 7, as well known in the art.
8 (non-prohibited state), received by 9, 10, 11
The audio is output by the speakers 10 and 11. In addition, the heads 12 and 1 are compatible with magnetic recording and reproducing devices.
3. The outputs from the amplifiers 14 and 15 are output by the speakers 10 and 11 through the audio output prohibition circuit 8 in the non-prohibited state.

Although it operates as described above under normal operating conditions, for example, in a set for Europe, the FM tuning frequency at FM reception is displayed on the display 21 by a 6-digit number. Has been done. That is, when the output frequency of the voltage controlled oscillator 4 is controlled by the control unit 16, the frequency in the tuning state at that time point is picked up by the prescaler 18, and the control unit 16 controls the driver 20 to set the tuning frequency. Are configured to be displayed on the display 21 as numbers.

In the case of the present invention, it is needless to say that the secret code input means is not limited to this, and other input means may be used, but attention is paid to the fact that the display 21 has a tuning frequency display function. However, it is used for inputting the above-mentioned personal identification code. That is, when the electronic circuit device is installed, the FM receiving mode is first set, an arbitrary specific tuning frequency is selected on the display 21 and a key operation from the control input unit 19 is performed. Numerical information corresponding to the tuning frequency is stored in the control unit 16. It should be noted that, for example, about 680 numbers can be given to the input of the personal identification code using the number display of the tuning frequency, and it can be considered that the number is practically acceptable.

As described above, once the personal identification code is stored, the number corresponding to the personal identification code is displayed when the power is turned on, for example, under a special operating condition as described with reference to FIG. 21. The control section 16 keeps the audio output prohibiting circuit shown in FIG. 1 in the prohibition state unless it is displayed correctly on 21 and collates with the previously stored personal identification code. Such a prohibited state can be resolved if correct input is made within the range of, for example, about 10 password input mistakes, but if the password input error exceeds 10 times, only a person who is given special authority Known to the user, that is, the reset circuit 23
Unless the reset function is activated by the above, the above prohibition state is prevented from being resolved, and the power is turned off.

FIG. 2 shows a processing mode of an embodiment relating to personal identification input in the control section. When the power is turned on, in this state, if the personal identification code is not stored in the apparatus as described above, the process proceeds to the route A shown in the figure, and the personal identification code Fo is made to correspond to the predetermined tuning frequency as described above. Memorize At the time of storing, [YES] is displayed on the display 21 and the normal operation state is entered. That is, it is possible to operate the radio receiver or the recording / playback function arbitrarily. In this state, when the power is turned off and then turned on again, the operation is as follows.

That is, this time, the route B shown in FIG. 2 is followed, and under some circumstances, it is checked whether or not the "vehicle + B power supply" shown in FIG. 1 is disconnected. That is, it is checked whether or not the electronic circuit device is driven under the condition that it is once removed from the vehicle. Whether or not it has been removed depends on whether the control unit 16 receives energy from the backup power supply 22 shown in FIG. 1 and whether or not there is a voltage at the INT shown in the figure, and for example, an electronic circuit device is mounted at a predetermined facility position on the passenger car. It is checked by determining whether or not there is a switch and storing it. If the "vehicle + B power supply" is not cut off, the route B shown in the figure can be directly followed to enter the normal driving state.

However, when the "vehicle + B power supply" is cut off, the operator displays a specific tuning frequency on the display 21 in the same manner as above, and issues a collation instruction from the control input section 19, for example. You will need to give. That is, the process proceeds to route C shown in FIG. If the entered code F matches the previous personal identification code Fo, the normal operation state is entered. However, if they do not match, 10
If re-inputting is permitted for a number of times and the input is not performed correctly, the electronic circuit device is put in the unusable state by turning off the power supply or the like.

It should be noted that an extremely small processor (microprocessor) is built in for storing the above-mentioned personal identification code, determining that the personal identification code is installed on the vehicle, collating the personal identification code, and generating a control output for the driving state prohibition circuit. It can be easily done only by.

[0016]

As described above, according to the present invention, the electronic circuit device is removed from the vehicle by the detecting means for detecting whether or not the power input to the microprocessor is interrupted. When detected, the microprocessor prohibits the normal operation state of the electronic circuit device, and the password input to the input means and the code input means select and set one password from a plurality of passwords. By doing so, the password code is collated with the memory code stored in the storage means, and if a match of the password is detected, the prohibition process can be canceled, so even if it is stolen, it will operate normally just by supplying power. Because it does not, it has a great effect of preventing theft. In addition, since the user can set the PIN code by himself, it is convenient for the user to freely select the PIN code that is easy to remember, and the PIN code is known to a third party compared to the one that is set in the factory. It gets harder. In addition, when installed in a vehicle or the like, it is not necessary to input a personal identification code, which is convenient for use. In addition, the structure is simpler and less expensive than the mechanical locking method.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating a processing mode of an embodiment of a control unit illustrated in FIG.

[Explanation of symbols]

 8 Audio output prohibition circuit 16 Control section 19 Control input section 21 Display 22 Memory backup power supply

Claims (1)

[Claims] 1. An electronic circuit device having a built-in microprocessor which is attached to a vehicle and which can be normally operated when the power is turned on, wherein the microprocessor determines whether or not the electronic circuit device is removed from the vehicle. Means for detecting by the microprocessor whether or not the power input to the electronic circuit device is interrupted, and when the detecting means detects that the power supply is removed, the microprocessor is controlled to detect the normal operation state of the electronic circuit device. Means for prohibiting the normal operation state, storage means capable of storing a personal identification code, code input means for inputting a personal identification code, personal identification code input by the code input means and the storage means read out from the storage means. The above-mentioned microprocessor-based collating means for collating the personal identification code, and one of the personal identification codes by the collating means. And a means for canceling the prohibition processing by the normal operation state prohibiting means when a match is detected, wherein the code input means selects and sets one of the secret codes to set it in the storage means. An electronic circuit device characterized in that it is configured so that it can shift to a normal operation state after storing a secret code.