The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 25, 2010
Filed:
Jan. 25, 2007
Thomas Tkacik, Phoenix, AZ (US);
John E. Spittal, Jr., Waddell, AZ (US);
Jonathan Lutz, Kitchner, CA;
Lawrence Case, Fountain Hills, AZ (US);
Douglas Hardy, Scottsdale, AZ (US);
Mark Redman, Gilbert, AZ (US);
Gregory Schmidt, Chandler, AZ (US);
Steven Tugenberg, Scottsdale, AZ (US);
Michael D. Fitzsimmons, Austin, TX (US);
Darrell L. Carder, Dripping Springs, TX (US);
Thomas Tkacik, Phoenix, AZ (US);
John E. Spittal, Jr., Waddell, AZ (US);
Jonathan Lutz, Kitchner, CA;
Lawrence Case, Fountain Hills, AZ (US);
Douglas Hardy, Scottsdale, AZ (US);
Mark Redman, Gilbert, AZ (US);
Gregory Schmidt, Chandler, AZ (US);
Steven Tugenberg, Scottsdale, AZ (US);
Michael D. Fitzsimmons, Austin, TX (US);
Darrell L. Carder, Dripping Springs, TX (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A processor, scan controller, and method for protecting sensitive information from electronic hacking is disclosed. To maintain the security of the sensitive data present in a processor, the scan controller denies access to the scan chain until data is cleared from scan-observable portions of the processor, then clears the scan chain again prior to exiting test mode and resuming normal operation. Clearing or otherwise modifying data stored in the scan-observable portions of a processor when transitioning to and/or from a test mode will prevent unauthorized personnel from simply shifting secure data out of the scan chain, and from pre-loading data into the scan chain prior to normal operation in an attempt to set sensitive state information.