7K320 SATA OEM Specification
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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
value of 268,435,455.
12.15
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.
12.15.1
Preserved software settings
If Software setting preservation is enabled, the following settings are preserved across COMRESET.
Otherwise settings are cleared across COMRESET.