Inside Macintosh: Devices /

Chapter 6 - Power Manager / Power Manager Reference

Power Manager Dispatch Routines / Controlling the Hard Disk

GetHardDiskTimeout

You can use the GetHardDiskTimeout function to find out how long the computer will wait before turning off power to the internal hard disk.

unsigned char GetHardDiskTimeout();

DESCRIPTION

The GetHardDiskTimeout function returns the amount of time the computer will wait after the last use of a SCSI device before turning off power to the internal hard disk. The value of GetHardDiskTimeout is expressed as the number of 15-second intervals the computer will wait before turning off power to the internal hard disk.

ASSEMBLY-LANGUAGE INFORMATION

The trap is _PowerMgrDispatch ($A09E). The selector value for GetHardDiskTimeout is 4 ($04) in the low word of register D0. The hard disk timeout value is returned in the low word of register D0.