Communications: electrical – Continuously variable indicating – With meter reading
Patent
1991-09-10
1993-09-14
Yusko, Donald J.
Communications: electrical
Continuously variable indicating
With meter reading
3408253, 34082531, 34082532, 307 102, G06F 704, H04Q 700
Patent
active
052453308
ABSTRACT:
Microprocessor-controlled apparatus, for example, a car radio whose microprocessor (5) is one-time programmable by the manufacturer of the apparatus. An external non-volatile memory (7) comprises a security variable (VAR) indicating whether the protection means is operational. In addition to a security code (SC), an arbitrary code series (KEY) of, for example, 20 bits is stored in the internal memory (51) of the microprocessor. Unauthorized disabling of the protection means by external interrogation of the non-volatile memory is only possible by assigning a value which corresponds to the code series to the security variable. However, the code series is inaccessible and can only be traced with great difficulty by means of trial and error methods.
REFERENCES:
patent: 4494114 (1985-01-01), Kaish
patent: 4604708 (1986-08-01), Lewis
patent: 4683462 (1987-07-01), Takeda et al.
patent: 4734896 (1988-03-01), Soma et al.
patent: 4743894 (1988-05-01), Bochmann
patent: 4808981 (1989-02-01), Seibold
patent: 4838377 (1989-06-01), Kozaki et al.
Liell, P., Elektronic, vol. 27, No. 13, p. 46, Nov. 1978.
Hill Andrew M.
Treacy David R.
U.S. Philips Corporation
Yusko Donald J.
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