Advanced Configuration and Power Interface
Advanced Configuration and Power Interface
(hardware, standard)The key element of the standard is power management with twoimportant improvements. First, it puts the OS in control ofpower management. In the currently existing APM model mostof the power management tasks are run by the BIOS, withlimited intervention from the OS. In ACPI, the BIOS isresponsible for the dirty details of communicating withhardware equipment but the control is in the OS.
The other important feature is bringing power managementfeatures now available only in portable computers todesktop computers and servers. Extremely low consumptionstates, i.e., in which only memory, or not even memory ispowered, but from which ordinary interrupts (real time clock,keyboard, modem, etc.) can quickly wake the system, are todayavailable in portables only. The standard should make theseavailable for a wider range of systems.
For ACPI to work the operating system, the motherboardchipset, and for some functions even the CPU has to bedesigned for it. Microsoft is heavily driving a move towardACPI, both Windows NT 5.0 and Windows 98 will support it.It remains to be seen how much hardware manufacturers willembrace the technology and whether other operating systemvendors will support it.
ACPI Information Page.