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:
Dec. 28, 2010
Filed:
Mar. 05, 2008
Paul G. Davis, San Jose, CA (US);
Paul G. Davis, San Jose, CA (US);
Microchip Technology Incorporated, Chandler, AZ (US);
Abstract
A method for providing field updates through the use of a memory emulation circuit with a content addressable memory (CAM) as the intelligent portion of the emulation circuit's arbiter. CAM circuitis comprised of configurable memory and is initially unprogrammed. Address requests are passed straight through multiplexerto Read Only Memory (ROM). As a result the data in the data location in ROMthat corresponds to the requested address will be output to data bus. If data locations in ROMbecome defective or contain data that needs to be upgraded the circuit implements a remapping of the data location. CAM circuitis programmed with direct addresses to be replaced in ROM. The direct addresses are paired to emulation addresses of data locations in configurable memory. Upgraded or substitute data is programmed into the configurable memoryat the paired emulation address. When address requests are received thereafter, CAM circuitcompares the address request to its stored direct addresses. If a match is found the paired emulation address is passed through multiplexerinstead of the direct address. As a result, the substitute or upgraded data in configurable memoryis output to data busin place of the old data.