Clock security ring
AssigneeInternational Business Machines Corporation
InventorsWilliam E. Haberkorn, Jr., Harold E. Roman
Life of this patent
Estimating the term…
Abstract
A clock security ring provides improved clock system error detection and (a.c.) fault isolation. The clock security ring is formed by a plurality of fault detection circuits and a plurality of error collection circuits each receiving inputs from respective subsets of the plurality of fault detection circuits. The error collection circuits comprise a logical network which provides a detected fault output for any fault pattern which leaves at least one fault detection circuit in a predefined correct state. Each of the subsets of fault detection circuits has an arbitrary grouping of fault detection circuits plus one fault detection circuit from an adjacent subset to thereby form a ring structure. The outputs of the error collection circuits are analyzed to provide fault isolation.
Claims11
A method for detecting and isolating clocking errors in a plurality of devices comprising the steps of:
- detecting clocking faults in each device of said plurality of devices and providing signals indicative of detected faults;
- grouping said signals in a plurality of subsets, each of said subsets having an arbitrary grouping plus one signal from an adjacent subset of signals to thereby form a ring structure;
- indicating an error condition in any subset for any fault pattern which leaves at least one signal in a first state, said first state representing a predefined, correct state;
- and
- analyzing any indicated error conditions to isolate alternating current faults.
A clock security ring for clock system error detection and alternating current fault isolation comprising:
- a plurality of fault detection circuits;
- a plurality of error collection circuits each receiving inputs from respective subsets of said plurality of fault detection circuits, each of said subsets including an arbitrary grouping of fault detection circuits plus one fault detection circuit from an adjacent subset to thereby form a ring structure;
- and
- means for analyzing outputs from said error collection circuits to provide fault isolation.
Dependencies are inferred from the claim text.