Advanced Configuration and Power Interface Specification

ACPI Source Language (ASL)Reference
Note: In the absence of an explicit Return () statement, the return value to the caller is undefined.
19.6.113 Revision (Constant Revision Integer)
Syntax
Revision => Integer
Description
The Revision operator returns an Integer containing the current revision of the AML interpreter.
Writes to this object are not allowed.
19.6.114 Scope (Open Named Scope)
Syntax
Scope (Location) {ObjectList}
Arguments
Opens and assigns a base namespace scope to a collection of objects. All object names defined
within the scope are created relative to Location. Note that Location does not have to be below the
surrounding scope, but can refer to any location within the namespace. The Scope term itself does
not create objects, but only locates objects within the namespace; the actual objects are created by
other ASL terms.
Description
The object referred to by Location must already exist in the namespace and be one of the following
object types that has a namespace scope associated with it:
• A predefined scope such as: \ (root), \_SB, \GPE, \_PR, \_TZ, etc.
• Device
• Processor
• Thermal Zone
• Power Resource
The Scope term alters the current namespace location to the existing Location. This causes the
defined objects within ObjectList to be created relative to this new location in the namespace.
Note: When creating secondary SSDTs, it is often required to use the Scope operator to change the
namespace location in order create objects within some part of the namespace that has been defined
by the main DSDT. Use the External operator to declare the scope location so that the ASL
compiler will not issue an error for an undefined Location.
Examples
The following example ASL code uses the Scope operator and creates several objects:
Version 6.0 883