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. 11, 1989
Filed:
Jul. 30, 1987
M Vittal Kini, Portland, OR (US);
Mark S Myers, Portland, OR (US);
Sunil Shenoy, Beaverton, OR (US);
Intel Corporation, Santa Clara, CA (US);
Abstract
A functional-redundancy checking logic for checking identical chips whose outputs are time-variant programmable. Window logic (40, 60) on each chip creates a window associated with each programmed transition, set pulse (14) and reset pulse (15). For the set pulse (14), on the rising edge (42) of the window, an error flip-flop (50) is set. The flip-flop is merely set at this time; an error is not flagged. The window remains open for a fixed time period. During the time period that the window is open, if the output pin (24) is ever correctly asserted, then the flip-flop (50) is reset, thus clearing the error flag. However, if the pin (24) always remains incorrectly asserted, indicating an error, then the error flip-flop (50) remains set. When the window closes on the falling edge (46) of the window pulse, an error report pulse is created via the AND (52). The value on the flip-flop (50) at this time is reported as an error (54). An identical circuit checks the programmable reset pulse ( 15).