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:
May. 06, 1997
Filed:
Dec. 30, 1994
Alan L Goodrum, Tomball, TX (US);
Gary B Kotzur, Spring, TX (US);
Kurt C Lantz, Spring, TX (US);
David F Heinrich, Tomball, TX (US);
Jeffrey T Wilson, Houston, TX (US);
Compaq Computer Corporation, Houston, TX (US);
Abstract
A hot spare boot circuit that automatically switches from a non-operational CPU to an operational CPU for powering up the computer system. In the multiprocessor computer system, a first CPU is designated to perform power on operations. If the first CPU fails, which is determined when a dead man counter in the hot spare boot circuit times out, the hot spare circuit ensures that the first CPU is in a disabled state. Next, the hot spare boot circuit identifies an operational second CPU, reinitializing certain ID information as necessary such that the second CPU can properly perform power on operations. The hot spare boot then awakens the second CPU, using a startup interprocessor interrupt in one embodiment, or simply negating the hard reset of the second CPU in a second embodiment. The second CPU then proceeds to perform the power on functions.