Data storage system having multimodal interblock gap detection utilizing

Abstract

A method and system for accurately reading and storing data as multiple data blocks on a removable data storage medium mounted within a data storage system. Each data block includes an initial acquisition data character and multiple diverse synchronization characters/bursts and adjacent data blocks are separated by a unique interblock gap character. A multimodal interblock gap character detection circuit is provided which may operate in a normal mode of operation or a stringent mode of operation, wherein an enhanced degree of certainty is required for detection of the interblock gap character. A predicted time window of occurrence for a next interblock gap character is generated in response to detection of an initial acquisition data character and at least one synchronization character within a data block. Additionally, a global clock count signal based upon multiple track outputs is generated each time a resynchronization burst is encountered. The multimodal interblock gap character detection circuit is then automatically switched from the stringent mode of operation to the normal mode of operation during the predicted time window, minimizing the possibility of erroneous interblock gap character detection during data block processing. In data blocks which are sufficiently large to utilize multiple unique end of block synchronization characters, the occurrence of each successive end of block synchronization character may be utilized to redefine the predicted time window with greater accuracy. Expiration of a predicted time window or the occurrence of a global clock count signal during an open predicted time window may then be utilized to generate a presumption of the occurrence of an interblock gap character; however, actual detection of the interblock gap character will override the prediction circuitry.