Patent · US Expired

State machine apparatus and methods for encoding data in serial form and decoding using multiple tables

US5596674A · kind A · utility

59Cited by
4References
22Claims
0Family size

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Key dates

Filing dateMay 26, 1993
Grant dateJan 21, 1997
Priority date
Expiry dateMay 26, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N19/91
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A serial data coding system is described in which a state machine (FIG. 5) is provided having a plurality of branching hierarchies N, N+1 of states each corresponding to a different decoding table. Depending upon each received bit of serial data, the state machine moves through these branching hierarchies of states until states 88 corresponding to valid codes are reached whereupon a valid code is decoded and the state machine reset to the start of that branching hierarchy. If it is desired to move between branching hierarchies, then an internal table selecting word is inserted into the stream of serial data to move the state machine into a table incrementing state 90 where a jump to another branching hierarchy of states may be made. In order to cope with an externally applied switching signal Y/C for switching the state machine between branching hierarchies, the state machine is first moved into one of a plurality of transfer states A, C, D etc. These states are chosen to be distinct from all other states of the state machine within any branching hierarchies so there is no ambiguity as to which state should be adopted after receipt of the externally applied switching signal Y/C.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.