Samsung WA31273A Technical Manual page 85

6-5-3-2 Standby mode
When a Standby command is received, or Auto-Power Down sequence is enabled and
Auto-Power Down Count is zero, then the drive enters the Standby mode.
In Stand-By mode, the drive interface is capable of accepting commands, but the media
is not immediately accessible.
6-5-3-3 Idle mode
When an Idle command is received, or Auto-Power Down sequence is enabled and
Auto-Power Down Count is zero, then the drive enters the Idle mode immediately.
After the drive entered the Idle Mode, it automatically transitions to the Standby Mode
upon expiration of a prescribed 1 minute spin-down counter.
In the Idle mode, the drive is capable of responding immediately to media access
requests. A drive in Idle mode may take longer to complete the execution of a command
than in Normal mode because it may have to activate ENDEC and R/W circuit.
6-5-3-4 Normal mode
In Normal mode, the drive is capable of responding immediately to media access
requests, and commands complete execution in the shortest possible time.
See specific power-related commands (6.4).
The power conditions in each mode is as shown in Table 6-11.
MODE
SLEEP
STANDBY
IDLE
NORMAL
* : See 6.4.18
1 : Active
0 : Inactive
x : don't care
WA31273A / WA32543A / WA33203A / WA32163A / WA31083A / WA32162A 6-41
Table 6-11. Power Conditions
SRST BSY
* x
x 0
x 0
x x
AT INTERFACE and ATA COMMANDS
DRDY Interface Active
x *
1 Yes
1 Yes
x Yes
Media
0
0
1
1