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:
Mar. 01, 1994
Filed:
Aug. 30, 1991
James Kardach, San Jose, CA (US);
Cau Nguyen, Milpitas, CA (US);
Intel Corporation, Santa Clara, CA (US);
Abstract
A dedicated memory area is provided on a microprocessor system for storing a customizable system interrupt service routine, processor state data at the time of interruption and a halt indicator indicating the CPU was interrupted from a halt state. The dedicated memory area is normally not mapped as part of the main memory space, thereby keep it inaccessible to the operating system and applications. An unmaskable system supervisor interrupt having higher priority than all other maskable and unmaskable interrupts is added to the CPU interrupts. The halt state indicator is set by the added interrupt of the CPU is in a halt state at the time of interruption. A RESUME instruction is added to the CPU instructions to provide recovery of the CPU to the state before it was interrupted. The Halt instruction is re-executed by the RESUME instruction if the halt state indicator remains set at the time of restoration. As a result, a system integrator or OEM may provide transparent system level interrupts with automated halt state restart that will operate reliably in any operating environment, and be relieved of the burden of managing halt state restart.