Patent ID: 6874073

Claim:
A method for managing data stored primarily in a read-only memory, which comprises: (a) providing a read-only memory with a memory area for storing data; (b) providing a rewritable memory having first and second memory areas, the first memory area of the rewritable memory storing data replacing the data stored in the memory area of the read-only memory; (c) diverting access from the data stored in the replaced memory area of the read-only memory to the data stored in the memory area of the rewriteable memory; (d) forwarding a current access operation to data to a memory used for a previous access operation; and (e) if, between the current access operation and the previous access operation, at least one of a change between the read-only memory and the rewriteable memory and a change between the two areas of the rewriteable memory is necessary, not using the stored data returned by the memory addressed in step (d), and again forwarding the current access operation to a correct memory; and (f) if, between the current access operation and the previous access operation, no change between the read-only memory and the rewriteable memory and between two areas of the rewriteable memory is necessary, using the data item returned by the memory addressed in step (d).