Table driven method and apparatus for automatic split field processing

Claim 1

A method of automatic split field calculation in a magnetic media system using a magnetic media having a plurality of circular tracks, each track having a plurality of radial servo marks wherein one of the servo marks is an INDEX mark and wherein all other servo marks are identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head for writing a sector to or reading a sector from one of a plurality of information regions, each region being positioned along one of the tracks between two adjacent servo marks such that each region has a capacity for storing information bits and wherein each sector includes a data field and a header field, the method having a capability to start an operation at one of the servo marks without waiting for the INDEX mark and comprising the steps of: a. providing a frame table for storing entries, each entry representing more than one split field flag and a number of sector pulses, with each flag indicating which of the fields has been split and the location of a split within the sector; b. detecting the number of a current servo mark representing the read/write head's position relative to the media; c. initializing the number of a target servo mark to equal the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of the servo mark which is a predetermined number of servo marks ahead of the current servo mark; d. converting the number of the target servo mark to the number of a relative target servo mark within a frame, the frame having a length smaller than the track length and including N sectors and M servo marks, N and M being integer values greater than zero; e. incrementing the number of the current servo mark as a next servo mark is detected; f. fetching an entry from the frame table corresponding to the number of the relative target servo mark, the entry representing a number of sector pulses to be automatically generated after the target servo mark, while waiting until the number of the current servo mark is equal to the number of the target servo mark; g. incrementing the number of the target servo mark as each next servo mark is detected, once the number of the current servo mark equals the number of the target servo mark, to identify an incremented target servo mark; h. converting the incremented target servo mark to an incremented relative target servo mark within a frame; i. fetching an entry from the frame table corresponding to the number of the incremented relative target servo mark, wherein after every N sectors and M servo marks, the frame repeats itself; and j. repeating steps g-i until the operation is complete.

Claim 2

A method of automatic split field calculation in a magnetic media system using a magnetic media having a plurality of circular tracks, each track having a plurality of radial servo marks wherein one of the servo marks is an INDEX mark and wherein all other servo marks are identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head for writing a sector to or reading a sector from one of a plurality of information regions, each region being positioned along one of the tracks between two adjacent servo marks such that each region has a capacity for storing information bits and wherein each sector includes a data field and a header field, the method having a capability to start an operation at one of the servo marks without waiting for the INDEX mark and comprising the steps of: a. providing a frame table for storing entries, each entry representing more than one split field flag and a number of sector pulses, with each flag indicating which of the fields has been split and the location of a split within the sector; b. detecting the number of a current servo mark representing the read/write head's position relative to the media; c. initializing the number of a target servo mark to equal the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of the servo mark which is a predetermined number of servo marks ahead of the current servo mark; d. converting the number of the target servo mark to the number of a relative target servo mark within a frame, the frame having a length smaller than the track length and including N sectors and M servo marks, N and M being integer values greater than zero; e. incrementing the number of the current servo mark as a next servo mark is detected; f. fetching an entry from the frame table corresponding to the number of the relative target servo mark, the entry representing a number of sector pulses to be automatically generated after the target servo mark, while waiting until the number of the current servo mark is equal to the number of the target servo mark; g. incrementing the number of the target servo mark as each next servo mark is detected, once the number of the current servo mark equals the number of the target servo mark, to identify an incremented target servo mark; h. converting the incremented target servo mark to an incremented relative target servo mark within a frame; i. fetching an entry from the frame table corresponding to the number of the incremented relative target servo mark, wherein after every N sectors and M servo marks, the frame repeats itself; and j. repeating steps g-i until the operation is complete.

Claim 12

An apparatus for automatic split field calculation in a magnetic media system using a magnetic media having a plurality of circular tracks, each track having a plurality of radial servo marks wherein one of the servo marks is an INDEX mark and wherein all other servo marks are identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head for writing a sector to or reading a sector from one of a second plurality of information regions, each region being positioned along one of the tracks between two adjacent servo marks such that each region has a capacity for storing information bits and wherein each sector includes a data field and a header field, the apparatus having a capability to start an operation at one of the servo marks without waiting for an INDEX mark and comprising: a. a detecting circuit for detecting the number of a current servo mark representing the read/write head's position relative to the media; b. an initializing circuit coupled to the detecting circuit for initializing the number of a target servo mark to equal the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of the servo mark which is a predetermined number of servo marks ahead of the current servo mark; c. a converting circuit coupled to the initializing circuit for converting the number of the target servo mark to the number of a relative target servo mark within a frame, the frame having a length smaller than the track length and including N sectors and M servo marks, N and M being integer values greater than zero; d. a first incrementing circuit coupled to the converting circuit for incrementing the number of the current servo mark as a next servo mark is detected; e. a second incrementing circuit coupled to the first incrementing circuit and the converting circuit for incrementing the number of the target servo mark as each servo mark is detected, once the number of the current servo mark is equal to the number of the target servo mark, to identify an incremented target servo mark; f. a frame table coupled to the converting circuit and to the incrementing circuit for storing entries, each of the entries representing a split field, a number of sector pulses to be automatically generated after the target servo mark, and more than one split field flag with each flag indicating which of the fields has been split and the location of a split within the sector; g. a retrieving circuit coupled to the frame table for fetching an entry from the frame table corresponding to the relative target servo mark, while waiting until the number of the current servo mark is equal to the number of the target servo mark and subsequently fetching corresponding subsequent entries from the frame table for each subsequent servo mark after the target servo mark corresponding to the incremented target servo mark and a relative servo mark within the frame, wherein after every N sectors and M servo marks, the frame repeats itself; and h. a generating circuit coupled to the retrieving circuit and to the operating circuit for automatically generating sector pulses.

Claim 13

An apparatus for automatic split field calculation in a magnetic media system using a magnetic media having a plurality of circular tracks, each track having a plurality of radial servo marks wherein one of the servo marks is an INDEX mark and wherein all other servo marks are identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head for writing a sector to or reading a sector from one of a second plurality of information regions, each region being positioned along one of the tracks between two adjacent servo marks such that each region has a capacity for storing information bits and wherein each sector includes a data field and a header field, the apparatus having a capability to start an operation at one of the servo marks without waiting for an INDEX mark and comprising: a. a detecting circuit for detecting the number of a current servo mark representing the read/write head's position relative to the media; b. an initializing circuit coupled to the detecting circuit for initializing the number of a target servo mark to equal the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of the servo mark which is a predetermined number of servo marks ahead of the current servo mark; c. a converting circuit coupled to the initializing circuit for converting the number of the target servo mark to the number of a relative target servo mark within a frame, the frame having a length smaller than the track length and including N sectors and M servo marks, N and M being integer values greater than zero; d. a first incrementing circuit coupled to the converting circuit for incrementing the number of the current servo mark as a next servo mark is detected; e. a second incrementing circuit coupled to the first incrementing circuit and the converting circuit for incrementing the number of the target servo mark as each servo mark is detected, once the number of the current servo mark is equal to the number of the target servo mark, to identify an incremented target servo mark; f. a frame table coupled to the converting circuit and to the incrementing circuit for storing entries, each of the entries representing a split field, a number of sector pulses to be automatically generated after the target servo mark, and more than one split field flag with each flag indicating which of the fields has been split and the location of a split within the sector; g. a retrieving circuit coupled to the frame table for fetching an entry from the frame table corresponding to the relative target servo mark, while waiting until the number of the current servo mark is equal to the number of the target servo mark and subsequently fetching corresponding subsequent entries from the frame table for each subsequent servo mark after the target servo mark corresponding to the incremented target servo mark and a relative servo mark within the frame, wherein after every N sectors and M servo marks, the frame repeats itself; and h. a generating circuit coupled to the retrieving circuit and to the operating circuit for automatically generating sector pulses.

Claim 29

An apparatus for automatic split field calculation in magnetic media systems using media which have a plurality of circular tracks, each track having an INDEX mark and having a predetermined number of sectors each including a data field and a header field, the media also having a plurality of radial servo marks each identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head, the apparatus having the capability to start from any servo mark on the track without waiting for the INDEX mark and comprising: a. a detecting circuit for detecting the number of a current servo mark corresponding to the position of the read/write head; b. a target servo mark counter coupled to the detecting circuit for storing the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of a servo mark which is a predetermined number of servo marks ahead of the current servo mark; c. a frame table comprising a plurality of entries coupled to the target servo mark counter, each entry representing split field and sector pulse information for a servo mark within the frame and more than one split field flag with each flag indicating which field has been split and the location of a split within the sector wherein the frame includes a number of sectors that is less than the predetermined number of sectors within the track; d. a comparator coupled to the target servo mark counter and to the detecting circuit, for comparing the number of the target servo mark counter to the number of the current servo mark; and e. an internal register network coupled to the frame table for storing split field and sector pulse information from the frame table for the target servo mark.

Claim 30

An apparatus for automatic split field calculation in magnetic media systems using media which have a plurality of circular tracks, each track having an INDEX mark and having a predetermined number of sectors each including a data field and a header field, the media also having a plurality of radial servo marks each identified by a unique number, wherein the media is rotated within the magnetic media system in relation to a read/write head, the apparatus having the capability to start from any servo mark on the track without waiting for the INDEX mark and comprising: a. a detecting circuit for detecting the number of a current servo mark corresponding to the position of the read/write head; b. a target servo mark counter coupled to the detecting circuit for storing the number of a first servo mark for which the system will begin operation, the number of the target servo mark being designated as the number of a servo mark which is a predetermined number of servo marks ahead of the current servo mark; c. a frame table comprising a plurality of entries coupled to the target servo mark counter, each entry representing split field and sector pulse information for a servo mark within the frame and more than one split field flag with each flag indicating which field has been split and the location of a split within the sector wherein the frame includes a number of sectors that is less than the predetermined number of sectors within the track; d. a comparator coupled to the target servo mark counter and to the detecting circuit, for comparing the number of the target servo mark counter to the number of the current servo mark; and e. an internal register network coupled to the frame table for storing split field and sector pulse information from the frame table for the target servo mark.