KR940008313B1 - Burglar alarm for car audio - Google Patents

Abstract

The burglarproof apparatus includies a microcomputer controlling an audio portion, an amplifier and a display, and has a secret code, a backup portion providing the microcomputer with power when power is cut off, a burglarproof display turning on a alarm lamp according to the control of the microcomputer when power is cut off, an input portion providing the microcomputer with the secret code and instructing a test mode to the microcomputer, and a display displaying a code input request according to the control of the microcomputer.

Description

Car audio anti-theft device

1 is a block diagram of a conventional anti-theft device.

2 is a flowchart of FIG.

3 is a flowchart according to another conventional anti-theft device.

4 is a block diagram of the present invention.

5 is a flowchart of the present invention.

The present invention relates to an anti-theft device of a car audio, indicating that the car audio set has an anti-theft function, including a key matrix for setting a password, and including a warning to inform it when the power is turned off. The present invention relates to a car audio anti-theft device to be operated only by a code input up to one time.

In general, an anti-theft device has a security code stored in the inside of the device, and when the power cord is connected to the power line of the audio device, the audio device can be operated if the same code as the security code is not input. It is not supposed to be. Therefore, even if the audio device is stolen, the thief cannot use the audio device without knowing the security code. However, if the merchant inspects at the store or the inspector inspects at the factory, the audio device will not operate unless the security code number is entered, thus causing a waste of time for entering the code number. Done. For this purpose, an anti-theft device for a vehicle audio device has been proposed that can eliminate the time waste when the inspection is carried out at a store or a factory.

This means that the input means for inputting the code, the memory means in which the security code is stored in advance, and the code inputted by the input means and the security code stored in the memory means when the power source is connected to the power line of the vehicle audio device In the anti-theft device of an on-vehicle audio device, comprising: first control means for making the on-vehicle audio device operable when the two are matched, the code input when a power source is connected to the power line; Based on other predetermined conditions, a second control means for making the on-vehicle audio device operable in a predetermined time is provided.

This is described as a main configuration of a general tape player for a vehicle radio, where (1) is an electronic tuner of radio, (2) is a PLL circuit of this tuner (1), and (3) is a cassette mechanism control unit of a tape player. Numeral 4 denotes an operation unit, which is provided with a preset key for instructing a radio station, a seek key for sequentially tuning from a radio station having a low frequency, a play key for starting playback of a cassette, a numeric key, and the like. Numeral 5 denotes a display section consisting of LEDs and liquid crystal lamps, and displays frequencies or various messages of tuned radio stations. 6 denotes a player power switch key, 7 a backup capacitor, and 8 a backflow prevention diode. (9) is the battery of the differential car, (10) is the ignition key of the car, and (11a, 11b) are the female and male connectors. Subsequently, reference numeral 12 denotes a microcomputer (hereinafter referred to as a microcomputer), a ROM 14 in which a processor 13 and a program and security code numbers used in the processor 13 are stored, and a RAM 15 for data recording. It consists of. In addition, the microcomputer 12 is provided with a power supply connection terminal Vcc, a battery detection terminal BAT, an ignition key detection terminal IGN, and a power switch key detection terminal POW.

Next, the operation by the above configuration will be described. First, when the connectors 11a and 11b are connected, the voltage of the battery 9 is supplied to the power supply connection terminal Vcc via the diode 8 and the battery is detected. Supplied to terminal BAT. The processor 13 detects that the voltage is supplied to the battery connection terminal BAT and performs the processing shown in the flowchart of FIG. That is, the process proceeds first to step S1 to determine whether the ignition key 10 is on. If this judgment result is "NO", the same judgment is repeated until "YES" is reached. When the determination result is "YES", the flow proceeds to step S2. In step S2, it is determined whether or not the switch 6 of the player is on. If this judgment result is "NO", the same judgment is repeated until "YES" is reached. When the determination result is "YES", the flow proceeds to step S3. In step S3, the player is made into an operable state and the flow advances to step S4. In step S4, the time is counted, and the flow advances to step S5. In step S5, it is determined whether the elapsed time of the player's operable state has exceeded 2 minutes, for example. If this determination result is "NO", the flow returns to step S4.

If the determination result is "YES", the flow proceeds to step S6. In step S6, the player is made inoperable, and the flow advances to step S7. In step S7, the display section 5 displays, for example, "Please enter a code", and the flow advances to step S8. In step S8, a code is input by the inspector from the numeric key of the operation part 4, and it progresses to step S9. In step S9, it is determined whether the code input by the inspector is the same as the security code stored in the ROM 14 in advance. If this determination result is "YES", the flow proceeds to step S10. In step S10, the player is placed in an operable state and the routine is terminated. After that, it can be used in the same manner as a normal player. If the judgment result is "NO", the flow proceeds to step S11. In step S11, it is determined whether or not the number of times of input of the code is the third time, for example. If this determination result is "NO", the flow returns to step S7. If the judgment result is "YES", this routine is terminated without any action. In this case, at step S6, since it is inoperable, it is not possible to use the player thereafter. That is, when the connectors 11a and 11b are connected, i.e., when the power supply is connected to the power line, the player becomes in an operable state for a predetermined time. Then, if the code inputted by inputting the code does not match the security code, the player becomes inoperable. It was made possible.

In addition, the US Patent No. 4,838, 377 is known in the flowchart, when the power switch is turned on as shown in FIG. 3 (step 41), it is determined whether it is theft mode, and if it is not theft mode, the normal operation is performed (step 51). In mode, it is determined whether the setting key is pressed when the power switch is turned on (step 43). If the set code is entered, normal operation is allowed (step 44). Therefore, when the set time is performed (step 45) and the set time elapses, for example, 3 minutes (step 46), the display of the line mode disappears (step 47), and the normal operation is prohibited by changing to the theft mode according to step 42. (Step 48). In this state, the code is input (step 49), and it is determined whether the input code matches the password (step 50).

If the secret code matches, normal operation is performed, otherwise theft mode is continued (step 50). When the setting key is operated at the same time as the power switch as in step 43, it operates normally during the setting time (3 minutes) and then changes to the theft mode, so that it is convenient to check the setting time, and the setting time has elapsed. If you do not press a separate secret code to activate the normal operation, the general operation for inspection, and if you do not know the secret code is convenient to prevent theft by not using, but the number of times to press the secret code There is no limit to the anti-theft protection is not limited, there is no anti-theft function to inform that there is a bad thing that thieves do not know this to be stolen.

The present invention is to solve this, it indicates that the car audio has an anti-theft function, when the test mode switch is turned on, the normal operation for a certain time, if not in the test mode to enter the secret input code, but less than three times It is characterized by strengthened anti-theft function by giving input. That is, according to the present invention, an input means for inputting a code, a storage means for storing a secret code in advance, and a code inputted by the input means and stored in the storage means when a power source is connected to a power line of a vehicle audio device An anti-theft device for a vehicle audio device having control means for operating the vehicle audio device only when the secret codes are compared with each other, the anti-theft device comprising: an anti-theft display unit for turning on an alarm light when the ignition is turned off In the test mode, the setup key operates normally only during the set time, and when it is not in the test mode, the secret code is entered but the secret code is entered only twice.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

A microcomputer (120) for controlling the audio unit and the amplifier unit, the display unit, and the input unit of the car audio while embedding a secret code; A backup unit 130 providing power to the microcomputer 120 when the power is cut off; An anti-theft display unit 140 for turning on an alarm lamp under control of the microcomputer 120 supplied with power by the backup unit 130 when the power is cut off; An input unit 150 for setting a password through the key matrix and providing the same to the microcomputer 120 and instructing the microcomputer 120 through the setting key matrix as a test mode; The display unit 160 key-matrix the code input request and the like according to the control signal of the microcomputer 120.

The anti-theft display unit 140 of the present invention includes a transistor Q2 in which the battery power source B + is selectively biased through the ignition switch IGN, the connection terminal 141, and the resistor R2; A transistor Q1 that is selectively biased according to the output of the microcomputer 120 and the output of the transistor Q2 controlled by the backup unit 130; When the transistor Q1 is turned on, the battery power source B + is preferably configured to include a light emitting device LED supplied through the resistor R1.

In the present invention, the microcomputer 120 controls the audio unit 170 and the amplifier unit 180, the display unit 160, and the input unit 150, and simultaneously embeds a password and a secret code, and includes a backup unit ( A system for providing an output to the anti-theft display unit 140 when the 130 is operated, a PLL for driving the audio unit 170, a driver for driving the display unit 160, a power supply terminal (VDD), chip enable, and the like. It has a CE theft-warning stage (ANTI-DET) and a mute stage (MUTE). The input unit 150 in the present invention includes a button for inputting a password and a key matrix for inputting a test mode. An output terminal of the audio unit 170 includes transistors Q3 and Q4, resistors R3 to R5, and a condenser C1 to mute the output of the audio unit 170; The amplifier unit 180 includes a speaker SP for amplifying and outputting the output of the audio unit 170. In addition to using the preset switch of the microcomputer 120 as the secret code input means of the present invention, the clock pulse of the electronic volume (CAM CODE) is counted, and the predetermined preset switch is used memory, and the electronic volume is input again and the memory is switched by the switch. It can be used.

The present invention will be described with the flowchart of FIG. The present invention is configured by connecting with the existing car audio, the battery power (B +) and the ignition switch (IGN) as shown in FIG. 4, in this state by turning on the power (PS), the microcomputer 120 is operated and at the same time audio The unit 170 and the anti-theft display unit 140 are selectively operated. That is, the microcomputer 120 determines whether the power source PS is on (step T1). Next, the display unit 160 displays a requirement to input a code (for example, "type the code") (step T2). Next, the microcomputer 120 determines whether a password or a specific key operation (number stored in the microcomputer 120 to operate in a test mode or a specific key operation) is performed through the input unit 150. (T3 stage). If it is determined that the test mode, the audio is normally operated for 2 minutes and 30 seconds (not particularly limited and adjustable), and the various performances of the audio equipment are checked and checked (T4 step). That is, by operating a password or a specific key (only people in a specific field, such as a car company or a repair shop, need to know the general public), the specific time required to check the normal operation of audio (for example, 2 minutes 30 seconds). Normal operation only for a while, so you can check whether it operates normally within 2 minutes and 30 seconds.

When the test mode is not in the step T3, the secret code is input through the input unit 150 (step T5). When the secret code is input, the microcomputer 120 checks whether the secret code matches the embedded secret code (step T6). If the secret codes do not match, it waits for one second and determines whether the input code is the third time (step T7).

Before knowing the secret code, there is no use to prevent theft, and when testing at the maintenance shop, etc., by pressing a specific button, it can be operated normally only for the set time, so that there can be tested for abnormalities. If it is not, it is possible to operate normally only when a password is entered, but only when the secret code is entered less than 3 times, it can be operated normally, thus increasing the reliability of the product by eliminating the chance of a third party to accidentally enter the secret code. Car Audio's anti-theft device.

Claims (3)

A microcomputer 120 for controlling the audio unit, the amplifier unit, and the display unit of the car audio while embedding a secret code; A backup unit 130 providing power to the microcomputer 120 when the power is cut off; An anti-theft display unit 140 for turning on an alarm lamp under control of the microcomputer 120 supplied with power by the backup unit 130 when the power is cut off; An input unit 150 for setting a password and providing it to the microcomputer 120 and instructing the microcomputer 120 in a test mode; Anti-theft device of the car audio, characterized in that it comprises a display 160 for displaying a code input request and the like according to the control signal of the microcomputer (120). The anti-theft display unit 140 includes: a transistor Q2 in which the battery power source B + is selectively biased through the ignition switch IGN, the connection terminal 41, and the resistor R2; A transistor Q1 which is selected and biased according to the output of the microcomputer 120 in which the backup unit 130 is controlled and the output of the transistor Q2; The anti-theft device of a car audio, characterized in that consisting of a light emitting device (LED) supplied with a battery power (B +) through a resistor (R1) when the transistor (Q1) is turned on. Judging whether the power is in the on state and displaying on the display a requirement to input a code number when the power is on (T1, T2); After determining whether the test mode by checking the password or the specific key operation according to the input instruction, if it is determined that the test mode, the audio is normally operated for a predetermined time to check and check various performances of the audio device (T3, T4) and ; Allowing a specific password to be entered when not in the test mode (T5); Checking whether the input password matches the embedded password (T6); If the password does not match, waits for one second and then determines whether it is the third time (T7); Car audio theft prevention method characterized in that to prevent theft of the car audio by performing a step (T8) to perform a normal operation if the input password and the built-in input number match.