Patent ID: 6075663
Filing Date: 2000-06-13
Classification: G06F,G11B

Abstract:
A serial interface read-back drive circuit for reading back data stored in state control registers within a read/write channel circuit of a magnetic disk drive, comprising:control means for controlling the operation of said magnetic disk drive and for generating a read-timing set value;serial write interface means for providing serial data, a serial data enable signal and a serial clock signal to enable various control states of said read/write channel circuit under the control of said control means;read-back enable signal generating means responsive to the read-timing set value, the serial clock signal and the serial data enable signal for generating a read-back enable signal defining a read-back enable interval; andread-back unit means responsive to the read-back enable signal for reading back the data of said state control registers during the read-back enable interval;wherein said read-back enable signal generating means comprises:a register for temporarily storing the read-timing set value of said control means;a counter for receiving the serial clock signal from the serial write interface means and for counting in accordance therewith to produce an output value;a comparator for generating a read timing start signal when the output value of said counter corresponds to said read-timing set value from said register; anda signal forming circuit for generating the read-back enable signal in accordance with the serial data enable signal from said serial write interface means and said read-timing start signal, and for ceasing generation of the read-back enable signal once the serial data enable signal is disabled.