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:
Jan. 01, 1991
Filed:
Oct. 12, 1988
John L Hartman, Minneapolis, MN (US);
American Standard Inc., New York, NY (US);
Abstract
In a system controller having multiple parts including a microprocessor, a main program for execution upon the microprocessor, and at least one clock interrupt handler portion, a method and apparatus for insuring proper operation comprised of providing a main counter and a delay counter in the main program providing a hardware watching timer, and providing in the clock interrupt handler means for starting the hardware watchdog timer and decrementing the main counter of the main program. The hardware watchdog timer reinitializes the main program in the event that the main program fails to respond to the clock interrupt handler and the delay counter reinitializes the main program and the clock interrupt handler in the event that the watchdog timer fails to operate. Therefore, each of the multiple parts of the system controller serve to insure the functionality of the other parts.