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Configuration

The ACPI namespace contains a tree of devices attached to the system. ACPI-aware operating systems walk this tree to enumerate devices and gain access to the device's data and control methods. In the ACPI namespace, an ACPI device description consists of a device object node and its children. Common children of device nodes include:

_ADR:
a bus-specific address. For example, this could be a PCI device and function number.
_HID:
the EISA ID of an on-board device. This is used to identify the device.
_UID:
the unit number of an on-board device. This is used to distinguish between same kind of device.
_CRS:
the current resource settings. This method produces a byte stream that is similar to a PnP resource encoding.
_PRS:
the possible resource settings. This method also produces a byte stream similar to a PnP resource encoding.
_SRS:
set resource settings. This method takes a PnP-encoded byte stream and uses it to set the device's configuration.
Note that the operating system accesses device data and methods through the ACPI-CA software layer (described in Section 2.2).


next up previous
Next: ACPI Power Management Up: ACPI Specified Components Previous: ACPI Specified Components
Takanori Watanabe 2002-04-13