Power-Management Modes - Seagate ST1.2 - Series 8 GB Removable Hard Drive Product Manual

2.7.4

Power-management modes

The drive provides programmable power management to provide greater energy efficiency. The drive features
the following power-management modes:
Table 3: Power-management modes
Power modes
Active (operating)
Idle, low power
Standby/Sleep
• Active mode
The drive is in Active mode during the read/write and seek operations.
• Low power idle mode
Drive enters Low Power Idle mode from Active Idle mode when the Advanced Power Management Level is
set above 80h and the Idle timer is reached at 2 seconds. Disc is spinning and head is parked and drive accepts
all commands and returns to Active mode any time disc access is necessary.
• Performance idle mode
The buffer remains enabled, and the drive accepts all commands and returns to Active mode any time disc
access is necessary.
• Standby/Sleep mode
The drive enters Standby mode when the host sends a Standby Immediate command. If the host has set the
standby timer, the drive can also enter Standby mode automatically after the drive has been inactive for a
specifiable length of time. The standby timer delay is established using a Standby or Idle command. In Standby
mode, the drive buffer is disabled, the heads are parked and the spindle is at rest. The drive accepts all
commands and returns to Active mode any time disc access is necessary.
• Standby timers
Each time the drive performs an Active function (such as read, write or seek), the standby timer is reinitialized
and begins counting down from its specified delay times to zero. If the standby timer reaches zero before any
drive activity is required, the drive makes a transition to Standby mode. In both Idle and Standby mode, the
drive accepts all commands and returns to Active mode when disc access is necessary.
10
Heads Spindle
Tracking Rotating
Parked Rotating
Parked Stopped
Buffer
Enabled
Disabled
Disabled
ST1.2 Series Product Manual, Rev. B