5.3 Host Commands
C141-E042-01EN 5-47
At command issuance (I/O registers setting contents)
1F7
H
(CM) 11111000
1F6
H
(DH)
××
´DVxx
1F5
H
(CH)
1F4
H
(CL)
1F3
H
(SN)
1F2
H
(SC)
1F1
H
(FR)
xx
xx
xx
xx
xx
At command completion (I/O registers contents to be read)
1F7
H
(ST) Status information
1F6
H
(DH)
×××
DV xx
1F5
H
(CH)
1F4
H
(CL)
1F3
H
(SN)
1F2
H
(SC)
1F1
H
(ER)
xx
xx
xx
xx
Error information
(21) IDLE (X’97’ or X’E3’)
Upon receipt of this command, the device sets the BSY bit of the Status register,
and enters the idle mode. Then, the device clears the BSY bit, and generates an
interrupt. The device generates an interrupt even if the device has not fully
entered the idle mode. If the spindle of the device is already rotating, the spin-up
sequence shall not be implemented.
By using this command, the automatic power-down function is enabled and the
timer immediately starts the countdown. When the timer reaches the specified
value, the device enters standby mode.
Enabling the automatic power-down function means that the device automatically
enters the standby mode after a certain period of time. When the device enters the
idle mode, the timer starts countdown. If any command is not issued while the
timer is counting down, the device automatically enters the standby mode. If any
command is issued while the timer is counting down, the timer is initialized and
the command is executed. The timer restarts countdown after completion of the
command execution.
The period of timer count is set depending on the value of the Sector Count
register as shown below.