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Adjustment of a read detection equalizer filter of a magnetic tape drive is conducted utilizing a required control pattern signal which comprises a required portion of a normal recording format of the magnetic tape. An example comprises a data set separator signal. The sensed required control patter

Adjustment of a read detection equalizer filter of a magnetic tape drive is conducted utilizing a required control pattern signal which comprises a required portion of a normal recording format of the magnetic tape. An example comprises a data set separator signal. The sensed required control pattern signal is processed with respect to a target reference pattern signal to adapt the read detection equalizer filter to the target reference pattern signal.

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1. A read detection system for a magnetic tape drive, comprising:an adjustable read detection equalizer filter for equalizing output signals from at least one magnetic read head; anda control processor responsive to at least a portion of a required control pattern signal sensed from a magnetic tape

1. A read detection system for a magnetic tape drive, comprising:an adjustable read detection equalizer filter for equalizing output signals from at least one magnetic read head; anda control processor responsive to at least a portion of a required control pattern signal sensed from a magnetic tape by said at least one magnetic read head, said required control pattern signal comprising a required portion of a normal recording format of said magnetic tape, said control processor processing said sensed required control pattern signal with respect to a target reference pattern signal to adapt said read detection equalizer filter to said target reference pattern signal. 2. The read detection system of claim 1, wherein said required control pattern signal additionally comprises a pattern of signals outside normal encoded data detection of said magnetic tape drive, and wherein said system additionally comprises a control pattern recognition sensor for recognizing said required control pattern signal, triggering said control processor to respond to said sensed required control pattern signal. 3. The read detection system of claim 2, wherein said required control pattern signal comprises a data set separator signal, and wherein said control pattern recognition sensor recognizes at least one signal of a greater time period than a maximum time period of normal encoded data detection of said magnetic tape drive, as said required control pattern signal. 4. The read detection system of claim 3, wherein said required control pattern signal comprises a data set separator signal, and wherein said control pattern recognition sensor recognizes a sequence of signals outside normal encoded data detection of said magnetic tape drive, as said required control pattern signal. 5. The read detection system of claim 1, wherein said control processor additionally cancels baseline distortion of said sensed required control pattern signal. 6. The read detection system of claim 5, wherein said control processor, in canceling said baseline distortion of said sensed required control pattern signal, conducts cosine compensation of said baseline distortion. 7. The read detection system of claim 1, wherein said required control pattern signal is repeated at a plurality of locations of a magnetic tape read by said magnetic tape drive, and said read detection system additionally comprises an error detector for detecting that reading of data of a magnetic tape exceeds a read error trigger, and, as the result of said detection, selecting at least one said required control pattern signal in close proximity to said data detected as exceeding said read error trigger. 8. The read detection system of claim 7, wherein said read detection equalizer filter comprises adjustable presets, and wherein said control processor temporarily adjusts said read detection equalizer filter from said presets. 9. The read detection system of claim 8, wherein said control processor additionally resets said read detection equalizer filter to said presets for a magnetic tape subsequently loaded in said magnetic tape drive. 10. The read detection system of claim 1, additionally comprising a loading detector for detecting loading of a magnetic tape in said magnetic tape drive, and, in response to detecting said loading of a magnetic tape, initiating operation of said control processor to respond to said sensed required control pattern signal. 11. The read detection system of claim 1, additionally comprising an ADC to convert said output signals to time based digital samples, and wherein said control processor responds to said time based digital samples of said required control pattern signal; and directly adapts said read detection equalizer filter to said target reference pattern signal. 12. The read detection system of claim 11, wherein said control processor additionally rotates a minimum slope point of a signal vector of said sensed required control pattern signal to an end of said signal vector and sets said minimum slope point to zero. 13. The read detection system of claim 1, additionally comprising an ADC to convert said output signals to time based digital samples, and wherein said control processor responds to said digital samples of said required control pattern signal; and additionally averages similar said digital samples within a window comprising a plurality of magnetic transitions. 14. A method for adjusting a read detection equalizer filter of a magnetic tape drive, comprising the steps of:sensing at least a portion of a required control pattern signal recorded on a magnetic tape, said required control pattern signal comprising a required portion of a normal recording format of said magnetic tape; andprocessing said sensed required control pattern signal with respect to a target reference pattern signal to adapt said read detection equalizer filter to said target reference pattern signal. 15. The method of claim 14, wherein said required control pattern signal additionally comprises a pattern of signals outside normal encoded data detection of said magnetic tape drive, and wherein said method additionally comprises the step of recognizing said required control pattern signal, triggering said sensing step. 16. The method of claim 15, wherein said required control pattern signal comprises a data set separator signal, and wherein said step of recognizing said required control pattern signal comprises recognizing at least one signal of a greater time period than a maximum time period of normal encoded data detection of said magnetic tape drive. 17. The method of claim 15, wherein said required control pattern signal comprises a data set separator signal, and wherein said step of recognizing said required control pattern signal comprises recognizing a sequence of signals outside normal encoded data detection of said magnetic tape drive. 18. The method of claim 14, wherein said step of processing said sensed required control pattern signal additionally comprises canceling baseline distortion of said sensed required control pattern signal. 19. The method of claim 18, wherein said step of canceling said baseline distortion of said sensed required control pattern signal comprises cosine compensation of said baseline distortion. 20. The method of claim 14, wherein said required control pattern signal is repeated at a plurality of locations of a magnetic tape read by said magnetic tape drive, and wherein said method additionally comprises the steps of detecting that reading of data of a magnetic tape by said magnetic tape drive exceeds a read error trigger; and, as the result of said detection, selecting at least one said required control pattern signal in close proximity to said data detected as exceeding said read error trigger. 21. The method of claim 20, wherein said read detection equalizer filter comprises adjustable presets, and wherein said step of adapting said read detection equalizer filter comprises a temporary adjustment from said presets. 22. The method of claim 21, additionally comprising the step of resetting said read detection equalizer filter to said presets for a magnetic tape subsequently loaded in said magnetic tape drive. 23. The method of claim 14, additionally comprising the step of detecting the loading of a magnetic tape in said magnetic tape drive, and as the result of said detection, conducting said step of processing said required control pattern signal recorded on said magnetic tape. 24. The method of claim 14, wherein said step of sensing said required control pattern signal additionally comprises determining time based digital samples of said required control pattern signal; and wherein said step of processing said sensed required control pattern signal with respect to a target reference pattern signal, comprises responding to said time based digital samples and directly adapting said read detection equalizer filter to said target reference pattern signal. 25. The method of c laim 24, wherein said step of processing said sensed required control pattern signal with respect to said target reference pattern signal additionally comprises rotating a minimum slope point of a signal vector of said sensed required control pattern signal to an end of said signal vector and setting said minimum slope point to zero. 26. The method of claim 14, wherein said step of sensing said required control pattern signal additionally comprises determining digital samples of said required control pattern signal; said step of processing said sensed required control pattern signal additionally comprises averaging similar said determined digital samples within a window comprising a plurality of magnetic transitions. 27. A magnetic tape drive, comprising:at least one magnetic read head for reading a magnetic tape;a drive mechanism for moving a magnetic tape relative to said at least one magnetic read head;an adjustable read detection equalizer filter for equalizing output signals from said at least one magnetic read head; anda control processor responsive to at least a portion of a required control pattern signal sensed from a magnetic tape by said at least one magnetic read head, said required control pattern signal comprising a required portion of a normal recording format of said magnetic tape, said control processor processing said sensed required control pattern signal with respect to a target reference pattern signal to adapt said read detection equalizer filter to said target reference pattern signal. 28. The magnetic tape drive of claim 27, wherein said required control pattern signal additionally comprises a pattern of signals outside normal encoded data detection of said magnetic tape drive, and wherein said system additionally comprises a control pattern recognition sensor for recognizing said required control pattern signal, triggering said control processor to respond to said sensed required control pattern signal. 29. The magnetic tape drive of claim 28, wherein said required control pattern signal comprises a data set separator signal, and wherein said control pattern recognition sensor recognizes at least one signal of a greater time period than a maximum time period of normal encoded data detection of said magnetic tape drive, as said required control pattern signal. 30. The magnetic tape drive of claim 29, wherein said required control pattern signal comprises a data set separator signal, and wherein said control pattern recognition sensor recognizes a sequence of signals outside normal encoded data detection of said magnetic tape drive, as said required control pattern signal. 31. The magnetic tape drive of claim 27, wherein said control processor additionally cancels baseline distortion of said sensed required control pattern signal. 32. The magnetic tape drive of claim 31, wherein said control processor, in canceling said baseline distortion of said sensed required control pattern signal, conducts cosine compensation of said baseline distortion. 33. The magnetic tape drive of claim 27, wherein said required control pattern signal is repeated at a plurality of locations of a magnetic tape, and said magnetic tape drive additionally comprises an error detector for detecting that reading of data of a magnetic tape exceeds a read error trigger, and, as the result of said detection, selecting at least one said required control pattern signal in close proximity to said data detected as exceeding said read error trigger. 34. The magnetic tape drive of claim 33, wherein said read detection equalizer filter comprises adjustable presets, and wherein said control processor temporarily adjusts said read detection equalizer filter from said presets. 35. The magnetic tape drive of claim 34, wherein said control processor additionally resets said read detection equalizer filter to said presets for a magnetic tape subsequently loaded in said magnetic tape drive. 36. The magnetic tape drive of claim 27, additionally compris ing a loading detector for detecting loading of a magnetic tape in said magnetic tape drive, and, in response to detecting said loading of a magnetic tape, initiating operation of said control processor to respond to said sensed required control pattern signal. 37. The magnetic tape drive of claim 27, additionally comprising an ADC to convert said output signals to time based digital samples, and wherein said control processor responds to said time based digital samples of said required control pattern signal; and directly adapts said read detection equalizer filter to said target reference pattern signal. 38. The magnetic tape drive of claim 37, wherein said control processor additionally rotates a minimum slope point of a signal vector of said sensed required control pattern signal to an end of said signal vector and sets said minimum slope point to zero. 39. The magnetic tape drive of claim 27, additionally comprising an ADC to convert said output signals to time based digital samples; and wherein said control processor responds to digital samples of said required control pattern signal; and additionally averages similar said digital samples within a window comprising a plurality of magnetic transitions. 40. A computer program product usable with a programmable computer processor having computer readable program code embodied therein, said programmable computer processor for adjusting an adjustable read detection equalizer filter of a read detection system for a magnetic tape drive, said adjustable read detection equalizer filter for equalizing output signals from at least one magnetic head, said computer program product comprising:computer readable program code which causes said programmable computer processor to respond to at least a portion of a required control pattern signal sensed from a magnetic tape by said at least one magnetic read head, said required control pattern signal comprising a required portion of a normal recording format of said magnetic tape; andcomputer readable program code which causes said programmable computer processor to process said sensed required control pattern signal with respect to a target reference pattern signal to adapt said read detection equalizer filter to said target reference pattern signal. 41. The computer program product of claim 40, wherein said computer readable program code additionally causes said programmable computer processor to cancel baseline distortion of said sensed required control pattern signal. 42. The computer program product of claim 41, wherein said computer readable program code causes said programmable computer processor to, in canceling said baseline distortion of said sensed required control pattern signal, conduct cosine compensation of said baseline distortion. 43. The computer program product of claim 40, wherein said required control pattern signal is repeated at a plurality of locations of a magnetic tape read by said magnetic tape drive, and said read detection system additionally comprises an error detector for detecting that reading of data of a magnetic tape exceeds a read error trigger, and, as the result of said detection, selecting at least one said required control pattern signal in close proximity to said data detected as exceeding said read error trigger; and wherein said computer readable program code causes said programmable computer processor to respond to said error detector detecting said exceeding of said read error trigger, processing said selected sensed required control pattern signal with respect to said target reference pattern signal. 44. The computer program product of claim 43, wherein said read detection equalizer filter comprises adjustable presets; and wherein said computer readable program code causes said programmable computer processor to temporarily adjust said read detection equalizer filter from said presets. 45. The computer program product of claim 44, wherein said computer readable program code additionally causes s aid programmable computer processor to reset said read detection equalizer filter to said presets for a magnetic tape subsequently loaded in said magnetic tape drive. 46. The computer program product of claim 40, wherein said magnetic tape drive additionally comprises a loading detector for detecting loading of a magnetic tape in said magnetic tape drive; and wherein said computer readable program code causes said programmable computer processor to respond to said loading detector detecting said loading of a magnetic tape, to initiate said processing of said selected sensed required control pattern signal with respect to said target reference pattern signal. 47. The computer program product of claim 40, wherein said computer readable program code causes said programmable computer processor to respond to time based digital samples of said required control pattern signal; and directly adapt said read detection equalizer filter to said target reference pattern signal. 48. The computer program product of claim 47, wherein said computer readable program code additionally causes said programmable computer processor to rotate a minimum slope point of a signal vector of said sensed required control pattern signal to an end of said signal vector and set said minimum slope point to zero. 49. The computer program product of claim 40, wherein said computer readable program code causes said programmable computer processor to respond to digital samples of said required control pattern signal; and additionally average similar said digital samples within a window comprising a plurality of magnetic transitions. 50. Logic for adjusting an adjustable read detection equalizer filter of a read detection system for a magnetic tape drive, said adjustable read detection equalizer filter for equalizing output signals from at least one magnetic head, said logic:responding to at least a portion of a required control pattern signal sensed from a magnetic tape by said at least one magnetic read head, said required control pattern signal comprising a required portion of a normal recording format of said magnetic tape; andprocessing said sensed required control pattern signal with respect to a target reference pattern signal to adapt said read detection equalizer filter to said target reference pattern signal. 51. The logic of claim 50, additionally cancelling baseline distortion of said sensed required control pattern signal. 52. The logic of claim 51, in canceling said baseline distortion of said sensed required control pattern signal, conducts cosine compensation of said baseline distortion. 53. The logic of claim 50, wherein said required control pattern signal is repeated at a plurality of locations of a magnetic tape read by said magnetic tape drive, and said read detection system additionally comprises an error detector for detecting that reading of data of a magnetic tape exceeds a read error trigger, and, as the result of said detection, selecting at least one said required control pattern signal in close proximity to said data detected as exceeding said read error trigger; and wherein said logic responds to said error detector detecting said exceeding of said read error trigger, processing said selected sensed required control pattern signal with respect to said target reference pattern signal. 54. The logic of claim 53, wherein said read detection equalizer filter comprises adjustable presets; and wherein said logic temporarily adjusts said read detection equalizer filter from said presets. 55. The logic of claim 54, wherein said logic additionally resets said read detection equalizer filter to said presets for a magnetic tape subsequently loaded in said magnetic tape drive. 56. The logic of claim 50, wherein said magnetic tape drive additionally comprises a loading detector for detecting loading of a magnetic tape in said magnetic tape drive; and wherein said logic responds to said loading detector detecting said loading of a magnetic tape, to i nitiate said processing of said selected sensed required control pattern signal with respect to said target reference pattern signal. 57. The logic of claim 50, wherein said logic responds to time based digital samples of said required control pattern signal; and directly adapts said read detection equalizer filter to said target reference pattern signal. 58. The logic of claim 57, wherein said logic rotates a minimum slope point of a signal vector of said sensed required control pattern signal to an end of said signal vector and sets said minimum slope point to zero. 59. The logic of claim 50, wherein said logic responds to digital samples of said required control pattern signal; and additionally averages similar said digital samples within a window comprising a plurality of magnetic transitions.