Patent ID: 9627081
Date: 2017-04-18
CPC Classifications: G06F,G11C

Claim:
1. A method for securing non-volatile memory comprising: updating a signature byte, stored within a non-volatile memory, from a default value specifying a write-protected mode to an updated value specifying a write-enabled mode; after updating the signature byte from the default value to the updated value, determining that the signature byte is set to a value associated with the write-enabled mode; write-protecting at least one sector of the non-volatile memory if the signature byte is not set to the value associated with the the write-enabled mode; after updating the signature byte from the default value to the updated value, preventing an entire sector in which the signature byte resides from being set to a predefined sector value unless a replacement firmware identifier associated with a replacement firmware matches a required replacement firmware identifier; determining whether a reflash of the non-volatile memory is authorized by comparing the replacement firmware identifier against the required replacement firmware identifier and indicating that reflash of the non-volatile memory is authorized if the replacement firmware identifier matches the required replacement firmware identifier; and if the reflash of the non-volatile memory is authorized, write-enabling the non-volatile memory, reflashing the non-volatile memory, and setting the signature byte to a value different from the value associated with the the write-enabled mode.