Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
// ASL Example
DefinitionBlock (
"forbook.aml",
// Output Filename
"DSDT",
// Signature
0x02, // DSDT Compliance Revision
"OEM",
// OEMID
"forbook",
// TABLE ID
0x1000
// OEM Revision
)
{ // start of definition block
OperationRegion(\GIO, SystemIO, 0x125, 0x1)
Field(\GIO, ByteAcc, NoLock, Preserve) {
CT01, 1,
}
Scope(\_SB)
// start of scope
Device(PCI0) {
// start of device
PowerResource(FET0, 0, 0) { // start of pwr
Method (_ON) {
Store (Ones, CT01) // assert power
Sleep (30)
// wait 30ms
}
Method (_OFF) {
Store (Zero, CT01) // assert reset#
}
Method (_STA) {
Return (CT01)
}
} // end of power
} // end of device
} // end of scope
} // end of definition block
5.5.1 ASL Statements
ASL is principally a declarative language. ASL statements declare objects. Each object has three
parts, two of which can be null:
Object := ObjectType FixedList VariableList
FixedList refers to a list of known length that supplies data that all instances of a given ObjectType
must have. It is written as (a, b, c,), where the number of arguments depends on the specific
ObjectType, and some elements can be nested objects, that is (a, b, (q, r, s, t), d). Arguments to a
FixedList can have default values, in which case they can be skipped. Some ObjectTypes can have a
null FixedList.
VariableList refers to a list, not of predetermined length, of child objects that help define the parent.
It is written as {x, y, z, aa, bb, cc}, where any argument can be a nested object. ObjectType
determines what terms are legal elements of the VariableList. Some ObjectTypes can have a null
variable list.
For a detailed specification of the ASL language, see Section 19, “ACPI Source Language (ASL)
Reference.” For a detailed specification of the ACPI Control Method Machine Language (AML),
upon which the output of the ASL translator is based, see Section 20, “ACPI Machine Language
(AML) Specification.”
218 April, 2015 Version 6.0