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:
Apr. 08, 1997
Filed:
Jan. 11, 1996
Patrick M Bland, Delray Beach, FL (US);
Richard G Hofmann, Lake Worth, FL (US);
Robert T Jackson, Boynton Beach, FL (US);
Nader Amini, Boca Raton, FL (US);
Bechara F Boury, Milpitas, CA (US);
Jayesh Joshi, Santa Clara, CA (US);
Intel Corporation, Santa Clara, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A device and method for power management of direct memory access ('DMA') slaves through DMA traps. The device comprises a plurality of registers coupled with conventional logic in order to generate a control signal for disabling direct memory access transfer requests for a powered-off DMA slave until the slave is re-powered. The method for managing power comprises steps of unmasking bits in a register containing information regarding which DMA slaves have been powered-off. Next, the DMA Controller consults a power management macro ('PMM') to determine whether a DMA transfer request involves a powered-off DMA slave. If not, the DMA transfer continues. However, if the DMA transfer does involve a powered-off DMA slave, then a main software application in operation is temporarily halted and the PMM generates a SMI signal and outputs the SMI signal to the central processing unit ('CPU') while keeping the disable control signal asserted, which effectively disables the DMA channel. The SMI signal invokes a software service routine which re-powers the powered-off DMA slave so that the main software application can continue.