Patent ID: 7752526
Filing Date: 2010-07-06
Classification: G06F,G06Q,G07F

Abstract:
1. An information storage device for use with a host, the information storage device comprising: one or more flash memories; an information processing circuit part that, according to an operation program, reads data stored in the one or more flash memories, writes data to the one or more flash memories, and performs other operations; and a transfer processing circuit part that, if read data read from the flash memories contains minor errors a count of which is equal to or less than a predetermined count, corrects the minor errors and transfers corrected read data to the host, and if the read data contains major errors the count of which is more than the predetermined count, transfers the read data containing the major errors and management data to the host without correcting the major errors, wherein the transfer processing circuit part comprises: a management data creation circuit part that creates the management data used for data corrections from write data transferred from outside; an error detection circuit part that detects whether the read data contains error locations, based on the read data and the management data created by the management data creation circuit part; and a first data correction and calculation circuit part that, when errors are detected by the error detection circuit part, calculates correction locations and correction data of the read data, and judges whether the read data contains major errors or minor errors, and wherein the information processing circuit part, when the first data correction and calculation circuit part judges that the read data contains minor errors, replaces the read data by the correction data in the correction locations thereof calculated by the first data correction and calculation circuit part, and transfers the corrected read data to the host, and when the first data correction and calculation circuit part judges that the read data contains major errors, transfers the read data and the management data to the host without correcting the read data.