Magnetic Disk Storage Apparatus With Phase Sync Circuit Having Controllable Response Characteristics

1. A magnetic disk storage apparatus comprising: a phase sync circuit for generating a read clock signal for controlling reading of data from a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase sync circuit to control the response characteristic of the phase sync circuit in accordance with the instruction; wherein the phase sync circuit includes a phase-locked loop circuit including: a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium; a charge pump connected to an output of the phase comparator, the charge pump having a gain which may be a controllable gain; a filter connected to an output of the charge pump, the filter having a filter characteristic which may be a controllable filter characteristic; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator; and wherein the instruction generated by the generating means includes at least one of information for controlling the gain of the charge pump and information for controlling the filter characteristic of the filter.

2. A magnetic disk storage apparatus comprising: a phase sync circuit for generating a read clock signal for controlling reading of data from a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read, the instruction being effective for preventing a false operation of the phase sync circuit caused by interference between data read from the magnetic disk-type storage medium, the interference occurring as a result of a shift in peaks of data stored at the access position; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase sync circuit to control the response characteristic of the phase sync circuit in accordance with the instruction; wherein the phase sync circuit includes a phase-locked loop circuit including: a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium; a charge pump connected to an output of the phase comparator, the charge pump having a gain which may be a controllable gain; a filter connected to an output of the charge pump, the filter having a filter characteristic which may be a controllable filter characteristic; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator; and wherein the instruction generated by the generating means includes at least one of information for controlling the gain of the charge pump and information for controlling the filter characteristic of the filter.

3. An information processing system comprising: a magnetic disk storage apparatus including a phase sync circuit for generating a read clock signal for controlling reading of data from a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic, means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read, and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase sync circuit to control the response characteristic of the phase sync circuit in accordance with the instruction, wherein the phase sync circuit includes a phase-locked loop circuit including a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium, a charge pump connected to an output of the phase comparator, the charge pump having a gain which may be a controllable gain, a filter connected to an output of the charge pump, the charge pump having a filter characteristic which may be a controllable filter characteristic, and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, and wherein the instruction generated by the generating means includes at least one of information for controlling the gain of the charge pump and information for controlling the filter characteristic of the filter; and information processing means connected to the magnetic disk storage apparatus for processing data read from the magnetic disk-type storage medium.

4. A magnetic disk storage apparatus comprising: delay means for receiving a first data signal reproduced from a magnetic disk-type storage medium and outputting a second data signal and a third data signal each corresponding to the first data signal, the delay means providing a controllable delay between the second data signal and the third data signal, thereby providing a controllable phase difference between the second data signal and the third data signal; a phase sync circuit for receiving the second data signal and outputting a read clock signal synchronized with the second data signal; a decoding circuit for receiving the third data signal and the read clock signal and decoding the third data signal based on the read clock signal; and means for controlling the delay of the delay means based on an access position on the magnetic disk-type storage medium at which the first data signal is being reproduced; wherein the phase sync circuit includes: a phase-locked loop circuit including a plurality of circuit elements, the circuit elements including at least one circuit element having a controllable response characteristic; means for generating an instruction for controlling the response characteristic of each of the at least one circuit element having a controllable response characteristic and outputting the instruction to a computer bus; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the at least one circuit element having a controllable response characteristic to control the response characteristic of each of the at least one circuit element having a controllable response characteristic in accordance with the instruction; wherein the phase-locked loop circuit includes: a phase comparator for receiving the second data signal and a clock signal and comparing the second data signal to the clock signal; a charge pump connected to an output of the phase comparator, the charge pump having a gain which may be a controllable gain; a filter connected to an output of the charge pump, the filter having a filter characteristic which may be a controllable filter characteristic; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the voltage-controlled oscillator, the clock signal being output from the phase sync circuit as the read clock signal synchronized with the second data signal; and wherein the instruction generated by the generating means includes at least one of information for controlling the gain of the charge pump and information for controlling the filter characteristic of the filter.

5. A magnetic disk storage apparatus comprising: an oscillator for generating a reference clock signal when data is to be written on a magnetic disk-type storage medium; a phase sync circuit for receiving the reference clock signal and outputting a write clock signal synchronized with the reference clock signal for controlling writing of the data on the magnetic disk-type storage medium based on an access position on the magnetic disk-type storage medium at which the data is to be written; an encoding circuit for receiving the write clock signal and the data to be written on the magnetic disk-type storage medium and encoding the data into a data signal based on the write clock signal; writing means for receiving the data signal and writing the data signal on the magnetic disk-type storage medium at the access position at which the data is to be written; out-of-phase detection means connected to the phase sync circuit for detecting an out-of-phase condition of the phase sync circuit wherein the write clock signal is out of phase with the reference clock signal; and means, connected to the writing means and the out-of-phase detection means, for preventing the writing means from writing the data signal on the magnetic disk-type storage medium when the out-of-phase detection means detects the out-of-phase condition of the phase sync circuit; wherein the phase sync circuit includes: a phase-locked loop circuit including a plurality of circuit elements, the circuit elements including at least one circuit element having a controllable response characteristic; p1 means for generating an instruction for controlling the response characteristic of each of the at least one circuit element having a controllable response characteristic and outputting the instruction to a computer bus; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the at least one circuit element having a controllable response characteristic to control the response characteristic of each of the at least one circuit element having a controllable response characteristic in accordance with the instruction; wherein the phase-locked loop circuit includes: a phase comparator for receiving the reference clock signal and a clock signal and comparing the reference clock signal to the clock signal; a charge pump connected to an output of the phase comparator, the charge pump having a gain which may be a controllable gain; a filter connected to an output of the charge pump, the filter having a filter characteristic which may be a controllable filter characteristic; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the clock signal being output from the phase sync circuit as the write clock signal synchronized with the reference clock signal; and wherein the instruction generated by the generating means includes at least one of information for controlling the gain of the charge pump and information for controlling the filter characteristic of the filter.

6. A magnetic disk storage apparatus comprising: a phase sync circuit for generating a read clock signal for controlling reading of data from a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; and means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to control the response characteristic of the phase-locked loop circuit in accordance with the instruction, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

7. A magnetic disk storage apparatus comprising: a phase sync circuit for generating a read clock signal for controlling reading of data from a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; and means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read, the instruction being effective for preventing a false operation of the phase sync circuit caused by interference between data read from the magnetic disk-type storage medium, the interference occurring as a result of a shift in peaks of data stored at the access position; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to control the response characteristic of the phase-locked loop circuit in accordance with the instruction, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the voltage-controlled oscillator having a gain; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

8. An information processing system comprising: a magnetic disk storage apparatus for reading data from a magnetic disk-type storage medium; and information processing means connected to the magnetic disk storage apparatus for processing data read from the magnetic disk-type storage medium; wherein the magnetic disk storage apparatus includes: a phase sync circuit for generating a read clock signal for controlling reading of data from the magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; and means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus, the instruction being generated based on an access position on the magnetic disk-type storage medium at which data is to be read; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to control the response characteristic of the phase-locked loop circuit in accordance with the instruction, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving a pulse signal and a clock signal and comparing the pulse signal to the clock signal, the pulse signal being a data signal reproduced from the magnetic disk-type storage medium; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the voltage-controlled oscillator having a gain; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

9. A magnetic disk storage apparatus comprising: delay means for receiving a first data signal reproduced from a magnetic disk-type storage medium and outputting a second data signal and a third data signal each corresponding to the first data signal, the delay means providing a controllable delay between the second data signal and the third data signal, thereby providing a controllable phase difference between the second data signal and the third data signal; a phase sync circuit for receiving the second data signal and outputting a read clock signal synchronized with the second data signal, the phase sync circuit having a controllable response characteristic; means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus; a decoding circuit for receiving the third data signal and the read clock signal and decoding the third data signal based on the read clock signal; and means for controlling the delay of the delay means based on an access position on the magnetic disk-type storage medium at which the first data signal is being reproduced; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to control the response characteristic of the phase-locked loop circuit in accordance with the instruction, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving the second data signal and a clock signal and comparing the second data signal to the clock signal; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the voltage-controlled oscillator having a gain, the gain of the voltage-controlled oscillator constituting a third parameter, the clock signal being output from the phase sync circuit as the read clock signal synchronized with the second data signal; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

10. A magnetic disk storage apparatus comprising: an oscillator for generating a reference clock signal when data is to be written on a magnetic disk-type storage medium; a phase sync circuit for receiving the reference clock signal and outputting a write clock signal synchronized with the reference clock signal for controlling writing of the data on the magnetic disk-type storage medium based on an access position on the magnetic disk-type storage medium at which the data is to be written, the phase sync circuit having a controllable response characteristic; means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a computer bus; an encoding circuit for receiving the write clock signal and the data to be written on the magnetic disk-type storage medium and encoding the data into a data signal based on the write clock signal; writing means for receiving the data signal and writing the data signal on the magnetic disk-type storage medium at the access position at which the data is to be written; out-of-phase detection means connected to the phase sync circuit for detecting an out-of-phase condition of the phase sync circuit wherein the write clock signal is out of phase with the reference clock signal; and means, connected to the writing means and the out-of-phase detection means, for preventing the writing means from writing the data signal on the magnetic disk-type storage medium when the out-of-phase detection means detects the out-of-phase condition of the phase sync circuit; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the computer bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to control the response characteristic of the phase-locked loop circuit in accordance with the instruction, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving the reference clock signal and a clock signal and comparing the reference clock signal to the clock signal; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator, the clock signal being output from the phase sync circuit as the write clock signal synchronized with the reference clock signal; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

11. A magnetic disk storage apparatus comprising: a phase sync circuit for generating a read clock signal for discriminating data from a pulse signal read out from an access position on a magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; and means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a bus, the instruction being an instruction for setting a response characteristic of a phase-locked loop circuit to a suitable response characteristic, the suitable response characteristic being a response characteristic suitable for generating the read clock signal such that the read clock signal is effective for discriminating data from the pulse signal read out from the access position on the magnetic disk-type storage medium; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to set the response characteristic of the phase-locked loop circuit to the suitable response characteristic, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving (1) the pulse signal read out from the access position on the magnetic disk-type storage medium and (2) a clock signal, and comparing the pulse signal to the clock signal; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.

12. An information processing system comprising: a magnetic disk storage apparatus for reading data from a magnetic disk-type storage medium; and information processing means connected to the magnetic disk storage apparatus for processing data read from the magnetic disk-type storage medium; wherein the magnetic disk storage apparatus includes: a phase sync circuit for generating a read clock signal for discriminating data from a pulse signal read out from an access position on the magnetic disk-type storage medium, the phase sync circuit having a controllable response characteristic; and means for generating an instruction for controlling the response characteristic of the phase sync circuit and outputting the instruction to a bus, the instruction being an instruction for setting a response characteristic of a phase-locked loop circuit to a suitable response characteristic, the suitable response characteristic being a response characteristic corresponding to a data transfer speed of the pulse signal read out from the access position on the magnetic disk-type storage medium; wherein the phase sync circuit includes: a phase-locked loop circuit having a controllable response characteristic; and means for receiving the instruction from the bus, storing the instruction, and outputting the instruction to the phase-locked loop circuit to set the response characteristic of the phase-locked loop circuit to the suitable response characteristic, thereby controlling the response characteristic of the phase sync circuit; wherein the phase-locked loop circuit includes: a phase comparator for receiving (1) the pulse signal read out from the access position on the magnetic disk-type storage medium and (2) a clock signal, and comparing the pulse signal to the clock signal; a charge pump connected to an output of the phase comparator and having a gain, the gain of the charge pump constituting a first parameter; a filter connected to an output of the charge pump and having a filter characteristic, the filter characteristic of the filter constituting a second parameter; and a voltage-controlled oscillator connected to an output of the filter for generating a clock signal and outputting the clock signal to the phase comparator; wherein at least one parameter selected from the group consisting of the first parameter constituted by the gain of the charge pump and the second parameter constituted by the filter characteristic of the filter is a controllable parameter; and wherein the instruction generated by the generating means includes information for controlling each of the at least one parameter.