Samsung spinpoint v40 Idle 97h,E3h, Idle Immediate 95h,E1h, Initialize Device Parameters 91h

DISK DRIVE OPERATION

6.4.7Idle (97h,E3h)

This command causes the drive to set BSY, enter the Idle Mode, clear BSY, and generate an interrupt. The interrupt is generated even though the drive may not have fully transitioned to Idle Mode.

If the drive is already spinning, the spin-up sequence is not executed.

If the Sector Count register is non-zero, then the automatic Idle Mode sequence is enabled, and the timer begins counting down immediately. If the Sector Count register is zero, the automatic power down sequence is disabled.

After the drive enters Idle Mode, it automatically transitions to Standby Mode upon expiration of a prescribed 1 minute spin-down timer.

Table 6-7Automatic Standby Timer Periods

Sector Count Register Contents		Corresponding Time-out Period
0	(00h)	Timeout Disabled
1-240 (01h-FOh)		(value * 5) seconds
241-251 (F1h-FBh)		(value - 240) * 30 minutes
252	(FCh)	21 minutes
253	(FDh)	8 hours
254	(FEh)	Reserved
255	(FFh)	21 minutes 15 seconds

6.4.8Idle Immediate (95h,E1h)

This command causes the drive to set BSY, enter Idle Mode, clear BSY, and generate an interrupt. The interrupt is generated even though the drive may not have fully transitioned to Idle Mode.

6.4.9 Initialize Device Parameters (91h)

This command enables the host to set the number of sectors per track and the number of heads minus 1, per cylinder. Upon receipt of the command, the drive sets BSY, saves the parameters, clears BSY, and generates an interrupt.

The only two register values used by this command are the Sector Count register which specifies the number of sectors per track, and the Drive/Head register which specifies the number of heads minus 1. The DRV bit designates these values to Drive 0 or Drive 1, as appropriate.

62 SpinPoint V40 Product Manual