Communications: electrical – Selective – Intelligence comparison for controlling
Reexamination Certificate
1997-11-07
2001-11-27
Zimmerman, Brian (Department: 2635)
Communications: electrical
Selective
Intelligence comparison for controlling
C340S005220, C070S278200
Reexamination Certificate
active
06323752
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic instrument which provides a resettable security code for preventing burglary and a method for rewriting the security code.
2. Background of the Invention
Of the electronic instruments powered by a battery, such as a car stereo unit, some have conventionally provided a security code set therefor. For example, consider that a thief mounts his stolen instrument in his own car. In this case, the stolen device requires him to input the same security code. Hence, if no match takes place between the security code pre-set in the instrument itself and the inputted security code, the thief cannot use the stolen device.
These kinds of electronic instruments are not operated until the preset security code is entered. This serves to prevent burglary.
The security code is thus required to be strictly protected. Actually, a correspondence table between the serial number of each instrument and the relevant security code is safekept in the manufacturer company or the service center of the company located closer to the user. The security code is distributed to the user as a label.
When the user mounts the electronic instrument to a car, for example, the user is required to enter the distributed security code for starting the instrument.
By the way, the correspondence table on which the security code is described is safekept in the manufacturer company or its branch office or distributed to the user as a lable. This is unfavorable to the security of the code. That is, if the user pastes the distributed label on the electronic instrument, another person can easily get the security code.
Even if another person gets the security code of the user, conventionally, the user cannot change the security code preset when manufacturing the electronic instrument. To avoid this disadvantage, for example, if the electronic instrument is arranged so that the user himself can reset the security code, then the initializing method for resetting the security code has to be made public, which leads to lowering the security level.
Under these circumstances, the present invention is made for overcoming the foregoing shortcomings. It is an object of the present invention to provide an electronic instrument which provides simplified means for managing the security code and a capability of setting the security code and a method for rewriting the security code.
SUMMARY OF THE INVENTION
The foregoing object is achieved by an electronic instrument arranged to enable the operation only if a match takes place between a security code pre-stored in the instrument itself and a security code entered by a user, which includes: a random number generator for generating a random number; an initializing code generator for generating a first initializing code corresponding to the random number generated by the random number generator; a display for displaying the random number generated by the random number generator; initializing code keys used by a user for entering a second initializing code based on the random number displayed on the display; a comparator for comparing the initializing code generated by the initializing code generator with the second initializing code entered through the initializing code keys; and a controller for enabling the reset of the security code pre-stored in the electronic instrument only if a match between the first initializing code and the second initializing code is determined by the comparator.
The foregoing object is achieved by a method for resetting the security code in the electronic instrument for enabling the operation only if a match takes place between the security code pre-stored in the electronic instrument and the security code entered by the user, which includes the steps of: generating a random number; entering a first initializing code corresponding to the generated random number; enabling a user to enter a second initializing code based on the generated random number; comparing the generated first initializing code with the second initializing code; and enabling reset of the security code pre-stored in the electronic instrument only if a match between the first initializing code and the second initializing code is determined by the comparator.
REFERENCES:
patent: 4494114 (1985-01-01), Kaish
patent: 4502048 (1985-02-01), Rehm
patent: 4759062 (1988-07-01), Traub et al.
patent: 5061923 (1991-10-01), Miller et al.
patent: 5091939 (1992-02-01), Cole
patent: 5144667 (1992-09-01), Pogue
patent: 5274370 (1993-12-01), Morgan et al.
patent: 5347267 (1994-09-01), Murray
patent: 5488358 (1996-01-01), Hamilton et al.
patent: 5604489 (1997-02-01), Hyatt, Jr.
patent: 5613388 (1997-03-01), Murphree
patent: 5708712 (1998-01-01), Brinkmeyer et al.
patent: 2120434 (1983-11-01), None
patent: 2244831 (1991-12-01), None
Matsufuji Daisaku
Takizawa Yuji
Maioli Jay H.
Sony Corporation
Zimmerman Brian
LandOfFree
Electronic instrument having resettable security code and... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electronic instrument having resettable security code and..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic instrument having resettable security code and... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2574341