Seagate ST9144 Power management mode descriptions, ST9051A power management mode descriptions

12 ST9144 Family Installation Guide, Rev. B

Power management mode descriptions

The ST9144 family drives feature four-phase power management with Active, Idle, Standby and Sleep modes. Power management is required for low-power portable systems, and is enabled through a system-dependent set-up procedure. Consult your system documentation for power management information.

ST9051A power management mode descriptions

Active mode. The drive is in Active mode during the read/write and seek operations.

Idle mode. At power-on the drive defaults to Idle mode after 5 seconds of inactivity. The spindle is up to speed. The heads are parked and latched away from the data zones for maximum data integrity. The drive is Ready and accepts all commands.

Standby mode. The drive enters Standby mode when a Standby Immediate command is received from the host. The drive also enters Standby mode after a specifiable length of time has elapsed with the drive in Idle mode. The Standby timer is system- dependent, and is usually established by the user with a system utility such as Setup. In Standby mode, the SeaCache buffer remains enabled, the heads are parked and the spindle is at rest. The drive accepts all commands, and returns to Active mode when disc access is necessary.

Sleep mode. The drive enters Sleep mode when a Sleep Imme- diate command is received from the host. The heads are parked and the spindle is at rest. The drive leaves Sleep mode when a hard or soft reset is sent from the host. After a soft reset is received, the drive exits Sleep mode with all current emula- tion/translation parameters intact.