Abstract:
A memory, particularly but not limitatively a Flash memory, comprises at least one data storage area (SEC1-SEC4) comprising a plurality of data storage locations (ML1-MLm), and an access circuitry (105,110) for accessing the data storage locations for either retrieving or altering a data content thereof, depending for example on a memory user request. The memory includes at least one first user-configurable flag element and a second user-configurable flag element. Both the at least one first and the second flag elements are used by a user to set a protected state of the respective data storage area against alteration of the content of the data storage locations thereof. The protected state defined by setting the first flag element is user-removable, i . e ., it can be removed by request from the user, so as to enable again the alteration of the content of the data storage area. On the contrary, the protected state defined by setting the second flag element is permanent and, once set, it cannot be removed: the data storage area becomes unalterable.
Abstract:
The invention relates to a method of protecting data in a semiconductor electronic memory comprising a memory matrix (2) and respective matrix address decoding (3) and predecoding (4) blocks. The method consists of using a protected memory portion (5) within said matrix (2) and respective dedicated decoding portions (6,7) for storing, into the protected portion (5), a protection code (CP) external to the address area of the matrix (2). The protection code (CP) can only be written and/or read through a command interpreter (8).