Data storage device reading servo sector while writing data sector
A data storage device is disclosed comprising a disk surface comprising a plurality of tracks, wherein each track comprises a plurality of data sectors and a plurality of servo sectors. The data storage device further comprises a head actuated over the disk surface, the head comprising at least one read element and at least one write element. Control circuitry is configured to use the head to write to a first data sector on the disk surface while simultaneously reading from a first servo sector on the disk surface.
1. A data storage device comprising:
a disk surface comprising a plurality of tracks, wherein each track comprises a plurality of data sectors and a plurality of servo sectors;
a head actuated over the disk surface, the head comprising at least one read element and at least one write element; and
control circuitry configured to:
use the head to write to a first data sector on the disk surface while simultaneously reading from a first servo sector on the disk surface; and
measure a reader/writer gap between the read element and the write element.
2. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to stop writing to the first data sector based on the measured reader/writer gap.
3. The data storage device as recited in claim 2 , wherein the control circuitry is further configured to stop writing to the first data sector based on the measured reader/writer gap and a format of the first servo sector.
4. The data storage device as recited in claim 3 , wherein the first servo sector comprises at least one gap field to compensate for a transient in a read signal emanating from the read element when the control circuitry stops writing to the first data sector.
5. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to start writing to the first data sector based on the measured reader/writer gap.
6. The data storage device as recited in claim 5 , wherein the control circuitry is further configured to start writing to the first data sector based on the measured reader/writer gap and a format of the first servo sector.
7. The data storage device as recited in claim 6 , wherein the first servo sector comprises at least one gap field to compensate for a transient in a read signal emanating from the read element when the control circuitry starts writing to the first data sector.
8. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to filter a read signal emanating from the read element when reading the first servo sector based on a frequency of data simultaneously written to the first data sector.
9. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to:
filter a read signal emanating from the read element when reading the first servo sector based on a frequency of data recorded in the first servo sector to generate a filtered read signal;
amplify the filtered read signal using a preamp to generate a preamplified read signal;
amplify the preamplified read signal using a variable gain amplifier to generate an amplified read signal;
generate signal samples based on the amplified read signal;
adjust a gain of the variable gain amplifier based on the signal samples; and
detect the data recorded in the first servo sector based on the signal samples.
10. The data storage device as recited in claim 1 , wherein the head comprises a first read element and a second read element and the control circuitry is further configured to:
configure the first read element to read the first servo sector to generate a first read signal comprising a data component based on the first servo sector and crosstalk interference due to simultaneously writing to the first data sector;
receive from the second read element a second signal comprising crosstalk interference due to simultaneously writing to the first data sector; and
combine the first read signal and the second signal to at least partially cancel the crosstalk interference from the first read signal.
11. The data storage device as recited in claim 1 , wherein:
the read element generates a read signal while reading the first servo sector; and
the read element is coupled to the control circuitry by a twisted pair transmission line that attenuates crosstalk interference in the read signal due to simultaneously writing to the first data sector.
12. A method of operating a data storage device, the method comprising:
using a head to write to a first data sector on a disk surface while simultaneously reading from a first servo sector on the disk surface; and
measuring a reader/writer gap between a read element and a write element of the head.
13. The method as recited in claim 12 , further comprising stopping writing to the first data sector based on the measured reader/writer gap.
14. The method as recited in claim 13 , further comprising stopping writing to the first data sector based on the measured reader/writer gap and a format of the first servo sector.
15. The method as recited in claim 14 , wherein the first servo sector comprises at least one gap field to compensate for a transient in a read signal emanating from a read element of the head when writing to the first data sector stops.
16. The method as recited in claim 12 , further comprising starting writing to the first data sector based on the measured reader/writer gap.
17. The method as recited in claim 16 , further comprising starting writing to the first data sector based on the measured reader/writer gap and a format of the first servo sector.
18. The method as recited in claim 17 , wherein the first servo sector comprises at least one gap field to compensate for a transient in a read signal emanating from a read element of the head when writing to the first data sector starts.
19. The method as recited in claim 12 , further comprising filtering a read signal emanating from a read element of the head when reading the first servo sector based on a frequency of data simultaneously written to the first data sector.
20. The method as recited in claim 12 , further comprising:
bandpass filtering a read signal emanating from a read element when reading the first servo sector based on a frequency of data recorded in the first servo sector to generate a filtered read signal;
amplifying the filtered read signal using a preamp to generate a preamplified read signal;
amplifying the preamplified read signal using a variable gain amplifier to generate an amplified read signal;
generating signal samples based on the amplified read signal;
adjusting a gain of the variable gain amplifier based on the signal samples; and
detecting the data recorded in the first servo sector based on the signal samples.
21. The method as recited in claim 12 , further comprising:
configuring a first read element to read the first servo sector to generate a first read signal comprising a data component based on the first servo sector and crosstalk interference due to simultaneously writing to the first data sector;
receiving from a second read element a second signal comprising crosstalk interference due to simultaneously writing to the first data sector; and
combining the first read signal and the second signal to at least partially cancel the crosstalk interference from the first read signal.
22. The method as recited in claim 12 , further comprising:
generating a read signal while reading the first servo sector; and
transmitting the read signal through a twisted pair transmission line that attenuates crosstalk interference in the read signal due to simultaneously writing to the first data sector.
23. A data storage device comprising:
a disk surface comprising a plurality of tracks, wherein each track comprises a plurality of data sectors and a plurality of servo sectors;
a head actuated over the disk surface, the head comprising at least one read element and at least one write element; and
control circuitry configured to:
use the head to write to a first data sector on the disk surface while simultaneously reading from a first servo sector on the disk surface;
filter a read signal emanating from the read element when reading the first servo sector based on a frequency of data recorded in the first servo sector to generate a filtered read signal;
amplify the filtered read signal using a preamp to generate a preamplified read signal;
amplify the preamplified read signal using a variable gain amplifier to generate an amplified read signal;
generate signal samples based on the amplified read signal;
adjust a gain of the variable gain amplifier based on the signal samples; and
detect the data recorded in the first servo sector based on the signal samples.
24. A data storage device comprising:
a disk surface comprising a plurality of tracks, wherein each track comprises a plurality of data sectors and a plurality of servo sectors;
a head actuated over the disk surface, the head comprising at least one a first read element, a second read element, and at least one write element; and
control circuitry configured to:
use the head to write to a first data sector on the disk surface while simultaneously reading from a first servo sector on the disk surface;
configure the first read element to read the first servo sector to generate a first read signal comprising a data component based on the first servo sector and crosstalk interference due to simultaneously writing to the first data sector;
receive from the second read element a second signal comprising crosstalk interference due to simultaneously writing to the first data sector; and
combine the first read signal and the second signal to at least partially cancel the crosstalk interference from the first read signal.
25. A method of operating a data storage device, the method comprising:
using a head to write to a first data sector on a disk surface while simultaneously reading from a first servo sector on the disk surface;
bandpass filtering a read signal emanating from a read element when reading the first servo sector based on a frequency of data recorded in the first servo sector to generate a filtered read signal;
amplifying the filtered read signal using a preamp to generate a preamplified read signal;
amplifying the preamplified read signal using a variable gain amplifier to generate an amplified read signal;
generating signal samples based on the amplified read signal;
adjusting a gain of the variable gain amplifier based on the signal samples; and
detecting the data recorded in the first servo sector based on the signal samples.
26. A method of operating a data storage device, the method comprising:
using a head to write to a first data sector on a disk surface while simultaneously reading from a first servo sector on the disk surface;
configuring a first read element to read the first servo sector to generate a first read signal comprising a data component based on the first servo sector and crosstalk interference due to simultaneously writing to the first data sector;
receiving from a second read element a second signal comprising crosstalk interference due to simultaneously writing to the first data sector; and
combining the first read signal and the second signal to at least partially cancel the crosstalk interference from the first read signal.