Advanced Configuration and Power Interface Specification

ACPI Source Language (ASL)Reference
19.3.4 ASL Macros
The ASL compiler supports some built in macros to assist in various ASL coding operations. The
following table lists some of the supported directives and an explanation of their function.
Table 19-354 Example ASL Built-in Macros
ASL Statement
EISAID (TextID)
Fprintf (Target,
FormatString,
FormatArgs)
Printf (FormatString,
FormatArgs)
ResourceTemplate ()
ToPLD
(PLDKeywordList)
ToUUID (AsciiString)
Unicode (StringData)
Description
Converts the 7-character text argument into its corresponding 4-byte numeric
EISA ID encoding. This can be used when declaring IDs for devices that are
EISA IDs.
Converts a format string to a series of string Concatenate operations and stores
the result to a Named Object.
Converts a format string to a series of string Concatenate operations and stores
the result to the Debug Object.
Used to supply Plug and Play resource descriptor information in human readable
form, which is then translated into the appropriate binary Plug and Play resource
descriptor encodings. For more information about resource descriptor
encodings, see Section 6.4, “Resource Data Types for ACPI.”
Converts a PLD Keyword List into a _PLD buffer.
Converts an ASCII string to a 128-bit buffer.
Converts an ASCII string to a Unicode string contained in a buffer.
19.3.5 ASL Data Types
ASL provides a wide variety of data types and operators that manipulate data. It also provides
mechanisms for both explicit and implicit conversion between the data types when used with ASL
operators.
The table below describes each of the available data types.
Table 19-355 Summary of ASL Data Types
ASL Data Type
[Uninitialized]
Buffer
Buffer Field
DDB Handle
Debug Object
Device
Description
No assigned type or value. This is the type of all control method LocalX variables
and unused ArgX variables at the beginning of method execution, as well as all
uninitialized Package elements. Uninitialized objects must be initialized (via Store
or CopyObject) before they may be used as source operands in ASL expressions.
An array of bytes. Uninitialized elements are zero by default.
Portion of a buffer created using CreateBitField, CreateByteField,
CreateWordField, CreateQWordField, CreateField, or returned by the Index
operator.
Definition block handle returned by the Load operator
Debug output object. Formats an object and prints it to the system debug port. Has
no effect if debugging is not active.
Device or bus object
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