Abstract: A method, circuit and drive for improving clock recovery in clock/data signals are provided. A timing reference is provided to a locking loop circuit, such as a PLL. The timing reference is updated based on an expectation of a frequency of a clock being recovered. A system clock tracked to each clock being recovered is outputted. A current frequency of each system clock is approximated, and the expectation updated based on the approximated current frequency of one or more of the system clocks. If the data stream includes data separated into a series of blocks, the update may be made after an end of a block and before a beginning of a succeeding block. The approximation may be made periodically and/or numerous times for each block.

Abstract: The system for detecting the edge of a moving data storage medium measures the ambient noise level of the magneto-resistive read head when the magneto-resistive read head is completely off the magnetic tape media. The system for detecting the edge of a moving data storage medium sets a signal threshold that is a predetermined increase over the magneto-resistive read head output signal generated by the ambient noise. The system for detecting the edge of a moving data storage medium then moves the magneto-resistive read head on to the magnetic tape media, where an increase in the magneto-resistive read head output signal is generated due to the friction of the moving magnetic tape coming into contact with the magneto-resistive read head, causing an increased noise level.

Abstract: The system for detecting the edge of a moving data storage medium measures the ambient noise level of the magneto-resistive read head when the magneto-resistive read head is completely off the magnetic tape media. The system for detecting the edge of a moving data storage medium sets a signal threshold that is a predetermined increase over the magneto-resistive read head output signal generated by the ambient noise. The system for detecting the edge of a moving data storage medium then moves the magneto-resistive read head on to the magnetic tape media, where an increase in the magneto-resistive read head output signal is generated due to the friction of the moving magnetic tape coming into contact with the magneto-resistive read head, causing an increased noise level.