Справочник Пользователя для Hitachi 100GB 7200 RPM HTE721010G9SA00
Модели
HTE721010G9SA00
Travelstar E7K100 (Serial ATA) Hard Disk Drive Specification
64
10.14 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 may be transferred by a single
command are increased by increasing the allowable sector count to 16 bits.
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
• 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.
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.
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 value of 268,435,455.
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 value of 268,435,455.
10.15 Software Setting Preservation Feature Set
When a device is enumerated, software will configure the device using SET FEATURES and other commands.
These software settings are often preserved across software reset but not necessarily across hardware reset. In
Parallel ATA, only commanded hardware resets can occur, thus legacy software only reprograms settings that are
cleared for the particular type of reset it has issued. In Serial ATA, COMRESET is equivalent to hard reset and a
non-commanded COMRESET may occur if there is an asynchronous loss of signal. Since COMRESET is
equivalent to hardware reset, in the case of an asynchronous loss of signal some software settings may be lost
without legacy software knowledge. In order to avoid losing important software settings without legacy driver
knowledge, the software settings preservation ensures that the value of important software settings is maintained
across a COMRESET. Software settings preservation may be enabled or disabled using SET FEATURES with a
subcommand code of 06h. Software settings preservation is enabled by default.
These software settings are often preserved across software reset but not necessarily across hardware reset. In
Parallel ATA, only commanded hardware resets can occur, thus legacy software only reprograms settings that are
cleared for the particular type of reset it has issued. In Serial ATA, COMRESET is equivalent to hard reset and a
non-commanded COMRESET may occur if there is an asynchronous loss of signal. Since COMRESET is
equivalent to hardware reset, in the case of an asynchronous loss of signal some software settings may be lost
without legacy software knowledge. In order to avoid losing important software settings without legacy driver
knowledge, the software settings preservation ensures that the value of important software settings is maintained
across a COMRESET. Software settings preservation may be enabled or disabled using SET FEATURES with a
subcommand code of 06h. Software settings preservation is enabled by default.
10.15.1 Preserved software settings
If Software setting preservation is enabled, the following settings are preserved across COMRESET. Otherwise
settings are cleared across COMRESET.
settings are cleared across COMRESET.
Setting
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