Patent ID: 6492920
Filing Date: 2002-12-10
Classification: G11B

Abstract:
A modulation method for performing a modulation to obtain a q-bit code word from a p-bit input data word (q>p) using plural coding tables, whereinthe plural coding tables comprise six coding tables each storing a code word and status information indicating a coding table for use in modulating a next input data word in order to obtain a next code word which satisfies a predetermined run length restriction rule even if the next code word is coupled directly with the code word, corresponding to each input data word; and in a specific coding table and another specific coding table of the six coding tables, code words stored corresponding to each predetermined input data word are determined to have an even/odd relation such that the number of â€œ1â€  in a code word in the specific coding table is even while the number of â€œ1â€  in a code word in the other specific coding table is odd so as to enable DSV control; and upon modulating the predetermined input data word, a code word which satisfies the predetermined run length restriction rule is outputted while the DSV control is carried out by referring to the six coding tables.