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. 10, 1990
Filed:
Nov. 28, 1988
Neal T Christensen, Wappingers Falls, NY (US);
Steven T Comfort, Poughkeepsie, NY (US);
Robert J Hurban, Old Bethpage, NY (US);
Bruce L McGilvray, Pleasant Valley, NY (US);
Arthur J Sutton, Cold Spring, NY (US);
James R Urquhart, Fishkill, NY (US);
David R Willoughby, Poughkeepsie, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of handling errors in the C bit of a storage key by modifying the INSERT STORAGE KEY (ISK) and the RESET REFERENCE BIT (RRB) instructions. If an error is found in the C bit during the execution of these instructions, microcode is instructed to refresh the C bit. The C bit is interrogated a second time to determine if the refreshed C bit is still in error. If the refreshed C bit is not in error a second time, then the first error was caused by a soft or transient error, and the instruction is continued. If the refreshed C bit is in error a second time then the first and second errors were caused by a permanent error such as a stuck bit, and a system recovery machine check error is generated. The handling of C bit errors is thus done in a dynamic fashion as the instructions are executed.