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:
Sep. 16, 1997
Filed:
Aug. 14, 1996
Robert Paul Gittinger, Austin, TX (US);
David Allen Spilo, Austin, TX (US);
Advanced Micro Devices, Inc., Sunnyvale, CA (US);
Abstract
A microcontroller includes an integrated memory and an integrated DMA controller. During testing, the DMA controller is used to perform read/write tests of background patterns and complements thereof to the integrated memory. The integrated memory need not contain the BIST logic typically required of integrated memories. By using the DMA controller to perform BIST-type testing, the tests are not hardware-bound. Typically, the BIST logic included in integrated memories is designed and tested during the design of the microcontroller. This design and test time is replaced by a (possibly shorter) task of generating test vectors for the requisite DMA transfers. The risk of having an error in the BIST test is reduced using the present testing method. Formerly, if BIST logic was found to be in error, new manufacturing masks for the microcontroller were required to repair the problem. A large time and monetary investment was required. The present method allows for correction and variation in the testing by resimulating the tests and creating new test vectors. The new test vectors may then be applied to previously manufactured microcontrollers.