Abstract: Systems and methods for detecting cycle slip are provided. In some embodiments, a waveform that represents data samples is received. The waveform may include a predetermined preamble and a predetermined postamble. A first value representing a phase of the predetermined preamble of the waveform may be computed. A second value representing a phase of the predetermined postamble of the waveform may be computed. A detection is made as to whether cycle slip occurred during sampling the received waveform based on a comparison of the first value with the second value.

Abstract: An apparatus, method, and system for providing a fine adjustment for transducing head positioning in a hard disk drive (HDD). The apparatus, method, and system include reading a positioning error field wherein the resulting signal is a substantially sinusoidal position error signal (PES), filtering the PES to remove low frequencies and attenuate high frequencies, sample the filtered PES at a multiple of the channel frequency, filter the higher frequency harmonics, down sample the PES, and provide a signal proportional to the amplitude of the down sampled PES. This signal is the reference signal to the head positioning servo.

Abstract: An apparatus, method, and system for providing a fine adjustment for transducing head positioning in a hard disk drive (HDD). The apparatus, method, and system include reading a positioning error field wherein the resulting signal is a substantially sinusoidal position error signal (PES), filtering the PES to remove low frequencies and attenuate high frequencies, sample the filtered PES at a multiple of the channel frequency, filter the higher frequency harmonics, down sample the PES, and provide a signal proportional to the amplitude of the down sampled PES. This signal is the reference signal to the head positioning servo.