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7K200 SATA OEM Specification
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The spare tracks for reassignment are located at regular intervals from Cylinder 0. As a result of
reassignment, the physical location of logically sequenced sectors will be dispersed.
12.13.1
Auto Reassign Function
The sectors that show some errors may be reallocated automatically when specific conditions are met.
The spare tracks for reallocation are located at regular intervals from Cylinder 0. The conditions for
auto-reallocation are described below.
Non recovered write errors
When a write operation can not be completed after the Error Recovery Procedure(ERP) is fully
carried out, the sector(s) are reallocated to the spare location. An error is reported to the host system
only when the write cache is disabled and the auto reallocation fails.
If the number of available spare sectors reaches 16 sectors, the write cache function will be disabled
only when the write cache is disabled and the auto reallocation fails.
If the number of available spare sectors reaches 16 sectors, the write cache function will be disabled
automatically.
Non recovered read errors
When a read operation fails after defined ERP is fully carried out, a hard error is reported to the
host system. This location is registered internally as a candidate for the reallocation. When a
host system. This location is registered internally as a candidate for the reallocation. When a
registered location is specified as a target of a write operation, a sequence of media verification is
performed automatically. When the result of this verification meets the criteria, this sector is
reallocated.
reallocated.
Recovered read errors
When a read operation for a sector failed once then recovered at the specific ERP step, this sector of
data is reallocated automatically. A media verification sequence may be run prior to the relocation
data is reallocated automatically. A media verification sequence may be run prior to the relocation
according to the pre-defined conditions.
12.14 48-bit Address Feature Set
The 48-bit Address feature set allows devices with capacities up to 281,474,976,710,655 sectors. This
allows device capacity up to 144,115,188,075,855,360 bytes. In addition, the number of sectors that
allows device capacity up to 144,115,188,075,855,360 bytes. In addition, the number of sectors that
may be transferred by a single command are increased by increasing the allowable sector count to 16
bits.
Commands unique to the 48-bit Address feature set are:
Flush Cache Ext
Read DMA Ext
Read Multiple Ext
Read Native Max Address Ext
Read Sector(s) Ext
Read Verify Sector(s) Ext
Set Max Address Ext
Write DMA Ext
Write Multiple Ext
Write Sector(s) Ext
The 48-bit Address feature set operates in LBA addressing only. Devices also implement commands
using 28-bit addressing, and 28-bit and 48-bit commands may be intermixed.
Support of the 48-bit Address feature set is indicated in the Identify Device response bit 10 word 83.
In addition, the maximum user LBA address accessible by 48-bit addressable commands is contained
in Identify Device response words 100 through 103.
When the 48-bit Address feature set is implemented, the native maximum address is the value
returned by a Read Native Max Address Ext command. If the native maximum address is equal to or
less than 268,435,455, a Read Native Max Address shall return the native maximum address. If the
native maximum address is greater than 268,435,455, a Read Native Max Address shall return a
native maximum address is greater than 268,435,455, a Read Native Max Address shall return a
value of 268,435,455.