This section summarizes the specific power management requirements for the SCSI bus class. Power management requirements for other device classes are defined in Part 4 of this guide.
21. Bus and device meet PC 98 power requirements
Required
Additional power management requirements are specified based on industry standards for the bus used by the controller and for the device. For more information, see the related chapter for the specific bus class in Part 3 in this guide. See also Part 4 of this guide for the related device class requirements based on compliance with the specific device class power management reference specification.
22. Hardware supports the STOP/START UNIT command as defined in the SCSI-2 specification
Required
The hardware in SCSI peripherals must be able to fully recover from a software-initiated spin down without rebooting the system or cycling power. To properly support power management on SCSI drives and to ensure that the operating system responds to appropriate driver calls, be sure to correctly implement the STOP/START UNIT command as defined in the SCSI-2 specification.
23. STOP/START UNIT command can be used to decrease power consumption
Recommended
Wherever appropriate—for example, for storage disks—the STOP UNIT command can be used to decrease the power consumption of the base platform. In order for any form of power management to work on SCSI, the device should be capable of supporting many tens of thousands of START/STOP UNIT commands over the life of a device.