Precompensation based on nearby data
View Patent ↗A circuit may be configured to precompensate the storage of data on a storage device. The magnitude and polarity of the precompensated time adjustment can be determined by looking up data patterns of storage regions in a table. A boundary can include storage regions of the device used to determine the precompensation.
1. An apparatus comprising:
a circuit configured to:
adjust a timing of a transition of a first signal to store data to a selected data storage region of a selected track of a data storage medium based on data patterns of another track adjacent to the selected track;
the selected data storage region is a structure that stores one bit of data;
a first bit group including the selected data storage region and at least one bit from the another track; and
the circuit is further configured to adjust the timing based on a bit pattern value of the first bit group;
another bit group including at least one bit from the another track not included in the first bit group; and
the circuit is further configured to adjust the timing based on the bit pattern value of the first bit group and a bit pattern value of the another bit group;
the apparatus further comprising:
a table configured to store timing adjustment values based on a bit pattern of the first bit group and another bit pattern from the another bit group; and
the circuit is further configured to determine the timing from the table based on the bit pattern of the first bit group and a determined adjacent bit pattern; and
the circuit further configured to:
determine if the another bit pattern is stored in a memory;
when the another bit pattern is stored in a memory, adjust the timing; and
when the another bit pattern is not stored in the memory, read the another bit pattern from the data storage medium into the memory; and
when the another bit pattern is not in the memory,
determine if a timer has expired;
when the timer has not expired, read the another bit pattern from the data storage medium into the memory and adjust the timing by the timing adjustment value; and
when the timer has expired, store data to the selected data storage region without adjusting the timing.
2. The apparatus of claim 1 comprising the circuit further configured to:
reconfigure the first bit group by removing a first set of storage regions and including another set of storage region.
3. The apparatus of claim 2 comprising the circuit further configured to:
reconfigure the another bit group by removing a first set of storage regions and including another set of storage regions.
4. The apparatus of claim 3 comprising the circuit further configured to:
read the another bit pattern from the data storage medium via two or more reader elements.
5. A method comprising:
adjusting, via a precompensation timing circuit (PCTC), a timing of a transition of a first signal to store data to a target data storage track of a data storage medium based on a data pattern that includes at least part of the target data track and part of an adjacent data track adjacent to the target data track;
storing data to the data storage medium using a precompensated transition timing based on the PCTC;
adjusting the timing based on a bit pattern value of the data pattern and another bit pattern value;
if the another bit pattern value is stored in a memory, then adjusting the timing,
else if a timer has expired, then storing data to the target data storage track without adjusting the timing; and
reconfiguring the data pattern by removing selected data regions of the adjacent data track and including other data regions.
6. The method of claim 5 further comprising:
when the timer has not expired:
reading data corresponding to the another bit pattern value from the data storage medium into the memory;
determining a timing adjustment value based on the data corresponding to the another bit pattern value and data corresponding to the bit pattern value; and
adjusting the timing based on the timing adjustment value.