Seagate ST1.3 ST1.3 Series Product Manual - Page 16

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, performance Idle, low power Standby/Sleep Heads Tracking Tracking Parked Parked Spindle Rotating Rotating Stopped Stopped Buffer Enabled Enabled Disabled Disabled • 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 Performance Idle mode when the Advanced Power Management Level is set between FDh and 80h, and the Idle timer is reached at 2 seconds (default setting is 2 seconds). Disc is not spinning and heads are 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 ST1.3 Series Product Manual, Rev. D