Patent ID: 8930798
Filing Date: 2015-01-06
Classification: G06F,H03M

Abstract:
1. A method for recording input data in s-level storage of a solid state storage device, where s f 2, the method comprising: encoding, by a processor, input data words in groups of M input data words in accordance with first and second BCH codes to produce, for each group, a set of M first codewords of the first BCH code such that a predetermined linear combination of the M first codewords produces a second codeword of the second BCH code, wherein the second BCH code is a sub-code of the first BCH code; recording the sets of M first codewords in the s-level storage; wherein each of the first and second codewords comprises N q-ary symbols where q=p converting each q-ary first codeword into an r-ary first codeword prior to recording in the s-level storage; and mapping successive sets of v r-ary symbols of each r-ary first codeword to respective corresponding levels of the s-level storage in accordance with a predetermined mapping scheme, and recording each set of v r-ary symbols as said corresponding level in the s-level storage, wherein s ! q and r ! s.