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. 21, 1993
Filed:
Nov. 07, 1989
Rashid N Khan, Cupertino, CA (US);
Cheng Chen, San Jose, CA (US);
Chien-Feng Cheng, Cupertino, CA (US);
Brian Verstegen, Sunnyvale, CA (US);
Win-Sheng Cheng, Cupertino, CA (US);
Aurav Gollabinnie, San Jose, CA (US);
Chips and Technologies, Inc., San Jose, CA (US);
Abstract
A circuit for waking a microprocessor from a sleep mode and providing it with its microprocessor clock long enough for a refresh, direct memory access (DMA) or master cycle operation to be done by external circuitry. The clock signal is then removed from the microprocessor to put it back into the sleep mode, thereby conserving energy. A hold signal is provided to the microprocessor to cause the microprocessor outputs to be put into a tri-state, high impedance condition, and thus relinquish control of the external bus to the external refreshing circuitry.