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. 30, 1996
Filed:
Jun. 08, 1995
Richard Finch, Austin, TX (US);
Eric Schieve, Austin, TX (US);
Dell USA, L.P., Austin, TX (US);
Abstract
A watchdog timer circuit of the present invention monitors a computer system (S) during diagnostic testing and resets the system when it is nonfunctioning. A real-time clock (RTC) (21), programmed by a central processing unit (CPU) (29) to run for a period of time, produces a reset signal after the period of time elapses. Typically this time period relates to a diagnostic program being run. The reset signal serves as an input to reset circuitry (28) which immediately transmits a nonmaskable interrupt (NMI) to the CPU (29) and, after a delay period, transmits a hardware reset signal to the CPU (29). When functioning properly, the CPU (29) prepares for the hardware reset signal that is produced by the reset circuitry (28) and avoids being reset by the hardware reset signal. However, when the CPU (29) is not functioning properly, the hardware reset signal resets the CPU (29). Additional circuitry stores information regarding where the system (S) failed during the diagnostic testing and retrieves such information for the user upon reset. An additional feature resets all of the components within the system (S) upon a CPU (29) reset via power reset circuitry.