Fujitsu MHT2020AT Product Manual page 121

*3) Automatic Acoustic Management (AAM)
The host writes to the Sector Count register with the requested acoustic
management level and executes this command with subcommand code 42h, and
then Automatic Acoustic Management is enabled. The AAM level setting is
preserved by the drive across power on, hardware and software resets.
High-speed seek to which gives priority to the performance operates as for
"Performance mode", and low-speed seek by which the seek sound is suppressed
operates as for "Acoustic mode".
Setting the seek mode by this command is applied to the seek operation in all
command processing.
(15) SET MULTIPLE MODE (X'C6')
This command enables the device to perform the READ MULTIPLE and
WRITE MULTIPLE commands. The block count (number of sectors in a
block) for these commands are also specified by the SET MULTIPLE MODE
command.
The number of sectors per block is written into the Sector Count register. The
IDD supports 2, 4, 8, 16 and 32 (sectors) as the block counts.
Upon receipt of this command, the device sets the BSY bit of the Status register
and checks the contents of the Sector Count register. If the contents of the Sector
Count register is valid and is a supported block count, the value is stored for all
subsequent READ MULTIPLE and WRITE MULTIPLE commands. Execution
of these commands is then enabled. If the value of the Sector Count register is
not a supported block count, an ABORTED COMMAND error is posted and the
READ MULTIPLE and WRITE MULTIPLE commands are disabled.
If the contents of the Sector Count register is 0, when the SET MULTIPLE
MODE command is issued, the READ MULTIPLE and WRITE MULTIPLE
commands are disabled.
When the SET MULTIPLE MODE command operation is completed, the device
clears the BSY bit and generates an interrupt.
C141-E192-01EN
AAM Level
Performance mode (Fast Seek)
Acoustic mode (Slow Seek)
Abort
Non Operate
5.3 Host Commands
Sector Count Register
C0h-FEh
80h-BFh
01h-7Fh
00h, FFh
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