Non-volatile memory read/write security protection feature...

Electrical computers and digital processing systems: memory – Storage accessing and control – Control technique

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C711S164000, C711S166000

Reexamination Certificate

active

06510501

ABSTRACT:

TECHNICAL FIELD
The present invention relates to security for programmable non-volatile memories (PNVM) and, in particular, to such a memory and associated circuitry equipped to handle and act upon, in a secure manner, a security status data stored within the memory itself.
BACKGROUND
Programmable non-volatile memories (e.g. electrically erasable programmable read-only memory and flash memory circuits) are well-known. In some applications, such as in control of safety functions in automobiles, security circuitry for read/write protection of the contents of PNVM circuits is commonly used. In this way, end-consumers are prevented from altering the contents of these memories and causing potentially life-threatening conditions. For example, security circuitry would commonly be used to protect the contents of an PNVM containing a program to control a vehicle's anti-lock brake system.
Conventionally, such security circuitry includes non-volatile security register circuitry, separate from the PNVM memory array itself, and the contents of which determine the security status of the PNVM contents. A major disadvantage of using non-volatile register circuitry for security functions is that it uses a large amount of chip area, and also that it requires special complex circuitry apart from the memory circuitry itself.
SUMMARY
A memory system in accordance with the invention includes a non-volatile memory to contain a security indication and program instructions. A volatile register is also provided.
Memory interface logic circuitry operates responsive to the contents of the volatile register, to selectively allow access to the memory. Security indication copying circuitry receives a reset signal for the memory system. In response to the reset signal, the copying circuitry causes the security indication to be copied into the volatile register as the contents thereof.


REFERENCES:
patent: 4998203 (1991-03-01), DiGulio
patent: 5442704 (1995-08-01), Holtey
patent: 5465349 (1995-11-01), Geronimi et al.
patent: 5481610 (1996-01-01), Doiron et al.
patent: 5491827 (1996-02-01), Hotley
patent: 5557743 (1996-09-01), Pombo et al.
patent: 5600818 (1997-02-01), Weikmann
patent: 5604713 (1997-02-01), Short et al.
patent: 5677891 (1997-10-01), Short et al.
patent: 5930826 (1999-07-01), Lee et al.
patent: 5963980 (1999-10-01), Coulier et al.
patent: 6032237 (2000-02-01), Inoue et al.
patent: 6148384 (2000-11-01), Devanagundy et al.
patent: 6154819 (2000-11-01), Larsen et al.
http://www.pcguide.com/ref, “The BIOS and the Software Layer Model”, “Hard Disk BIOS and Capacity Factors”, “Role of the BIOS in Hard Disk Access”, “The Int13h Interface”, “Two and Four Disk BIOS IDE Support”.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Non-volatile memory read/write security protection feature... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Non-volatile memory read/write security protection feature..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Non-volatile memory read/write security protection feature... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3068625

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.