Signal processing technique for preventing delay in read time from retry operations
View Patent ↗The present invention enables recovery of data reading, even when thermal asperities or defective media will make it impossible to increase the number of retries or to read the data, occur in the AGC/PLL part. In a device for writing and reading information, when an error occurs in the region of the recording media where the AGC/PLL signal is written, and if that information is written continuously to several sectors, then data reading is performed by using the AGC/PLL of the following sector, without performing a retry, or by performing a minimum number of retries.
1. A data read method, comprising the step of:
when reading out data written to sectors on a disk medium, data in a read-out target sector and a following sector next to said data is read out using an output amplitude control information and a read clock control information of a sector read out previously time-wise to said read-out target sector.
2. The data read method according to claim 1 , comprising the steps of:
opening a read gate; and
halting read-out control for a portion of said following sector;
wherein said output amplitude control information and said read clock control information for said previously read sector is held.
3. A method for an information write/read device having a function for writing or reading a plurality of sectors in a continuous fashion, comprising the steps of:
when reading continuously written data, a timer is started upon termination of control of said read operation for a sector unit; and
provided that a time period until said start of control of the read operation for a following sector unit is within a predetermined period of said timer, an output amplitude control information and a read clock control information of a preceding sector is held.
4. A method for an information write/read device having a function for writing or reading a plurality of sectors in a continuous fashion, comprising the step of:
when continuously written sector groups are read continuously, instead of using an output amplitude control information and a read clock control information pertaining to a head sector of respective sector group, data reading is performed using a control information immediately preceding said head sector and a control information of a following sector read continuously to said head sector.
5. A signal processing circuit, comprising:
a read control signal which does not close between sectors during a period of continuous reading of a plurality of sectors;
a signal which halts reading control corresponding to a head part of a following sector; and
a function for holding an output amplitude control information and a read clock control information in response to said signal which halts reading control.
6. A signal processing circuit, comprising:
a function for starting a timer upon termination of control of
a read operation of a sector unit; and
a function for holding an output amplitude control information and an read clock control information of a preceding sector, provided that a time period until a start of control of said read operation for a following sector unit is within a predetermined period of said timer.
7. A signal processing circuit in an information write/read device having a function for writing or reading a plurality of sectors in a continuous fashion, the signal processing circuit comprising:
first function for reading continuously written sector groups continuously; and
second function for reading data continuously when first function is activated, instead of using an output amplitude control information and a read clock control information pertaining to a head sector of respective sector group, using a control information immediately preceding said head sector and a control information of a following sector.
8. A signal processing circuit in an information write/read device having a function for writing or reading a plurality of sectors in a continuous fashion, the signal processing circuit comprising:
first function for reading continuously written sector groups continuously;
second function for reading data when first function is activated, instead of using an output amplitude control information and a read clock control information pertaining to a head sector of respective sector group;
third function for enabling arbitrarily an offset information between said control information immediately preceding said head sector and a control information of a follwing sector read continuously; and
fouth function for sending said offset information to a read channel.
9. An information write/read device using any one of the methods according to claim 1 to 3 , comprising:
a function for reading data spanning a plurality of sectors; and
a function for reading data by temporarily halting reading control of a following sector.
10. An information write/read device using any one of the methods according to claim 1 to 3 , comprising:
a function for writing data continuously spanning a plurality of sectors.
11. An information write/read device using any one of the methods according to claim 1 to 3 , comprising:
first function for writing data continuously to a plurality of sectors; and
second function for deleting at least a portion where a particular cyclical pattern has been written in a second or more sectors.
12. An information write/read device using any one of the methods according to claim 1 to 3 , comprising:
first function for writing or reading data spanning a plurality of sectors; and
second function for waiting for a head sector of whole said data or a head sector of a sector group consisting of several sectors, if a head has arrived at a sector other than said head sector, to arrive for writing or reading.