Fujitsu MPE3043AE, Руководство по эксплуатации продукта

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C141-E093-01EN 5 - 50
Table 5.8 Features Register values (subcommands) and functions (2/2)
Features Resister Function
X’D6’ SMART Write Log Sector:
A device which receives this sub-command asserts the BSY bit and when it has
prepared to receive data from the host computer, it sets DRQ and clears the BSY
bit. Next, it receives 512 bytes of data from the host computer and writes the
specified log sector in the SN register. 01h should be specified in the SC register.
SN: Log sector
80h-9Fh: Host vendor log
* The host can write any desired data in the host vendor log.
X’D8’ SMART Enable Operations:
This subcommand enables the failure prediction feature. The setting is
maintained even when the device is turned off and then on.
When the device receives this subcommand, it asserts the BSY bit, enables the
failure prediction feature, then clears the BSY bit.
X’D9’ SMART Disable Operations:
This subcommand disables the failure prediction feature. The setting is
maintained even when the device is turned off and then on.
When the device receives this subcommand, it asserts the BSY bit, disables the
failure prediction feature, then clears the BSY bit.
X’DA’ SMART Return Status:
When the device receives this subcommand, it asserts the BSY bit and saves the
current device attribute values. Then the device compares the device attribute
values with insurance failure threshold values. If there is an attribute value
exceeding the threshold, F4h and 2Ch are loaded into the CL and CH registers. If
there are no attribute values exceeding the thresholds, 4Fh and C2h are loaded
into the CL and CH registers. After the settings for the CL and CH registers have
been determined, the device clears the BSY bit.
X’DB’ SMART Enable/Disable Auto Off-line:
This sets automatic off-line data collection in the enabled (when the SC register
specification
≠
00h) or disabled (when the SC register specification = 00) state.
This setting is preserved whether the drive’s power is switched on or off.
If four hours have passed since the power was switched on, or since the last time
that off-line data were collected, off-line data collection is performed without
relation to any command from the host computer.
The host must regularly issue the SMART Read Attribute Values subcommand (FR register =
D0h), SMART Save Attribute Values subcommand (FR register = D3h), or SMART Return
Status subcommand (FR register = DAh) to save the device attribute value data on a medium.
Alternative, the device must issue the SMART Enable-Disable Attribute AutoSave
subcommand (FR register = D2h) to use a feature which regularly save the device attribute
value data to a medium.
The host can predict failures in the device by periodically issuing the SMART Return Status
subcommand (FR register = DAh) to reference the CL and CH registers.