Patent ID: 6317850
Filing Date: 2001-11-13
Classification: G06F,G11B

Abstract:
A disk drive comprising:(a) a disk including a plurality of addressable locations containing stored data;(b) signal processing circuitry comprising:reading means responsive to the stored data for producing a read signal; andmeans responsive to the read signal for producing decoded data that is subject to errors;(c) a control system, responsive to the decoded data, for computing an error rate measurement by:performing a first data-recovery procedure conducted under conditions providing for increasing the probability of achieving a first successful data-recovery step;performing a second data-recovery procedure conducted under conditions providing for increasing the probability of achieving a second successful data-recovery step;generating a first accumulated value representing occurrences of the first successful data recovery step;generating a second accumulated value representing occurrences of the second successful data recovery step;weighting the first accumulated value by a first weight to generate a first weighted value;weighting the second accumulated value by a second weight different than the first weight to generate a second weighted value; andcomputing the error rate measurement by combining the first and second accumulated values and the first and second weighted values.