An T Le

US Patent:

54348706, Jul 18, 1995

Filed:

Apr 17, 1992

Appl. No.:

7/870525

Inventors:

Michael K. Benton - Malvern PA
An Le - Philadelphia PA

Assignee:

Unisys Corporation - Blue Bell PA

International Classification:

G06F 1110

US Classification:

371 371

Abstract:

Disclosed is an apparatus and method for verifying the authenticity of a circuit board incorporated in a system. The method employs signal representing a unique identifier, such as a serial number and an associated error check code, to identify the circuit board. The identifier signal is passed from the circuit board to the system when the circuit board is initialized. To verify that a circuit board is authentic, the error check code (ECC) represented in the second part of the circuit board's identifier signal is verified. If the ECC is not correct then the circuit board is left unused. Next, the first part of the identifier signal (e. g. the serial number) is compared to the identifier signals for all other circuit boards mounted within the system. If a match of any two identifier signals is found, all circuit boards associated with the common identifier signal are left unused. If no duplicates are found and the ECC was correct, the circuit board is permitted to function.