Advanced Configuration and Power Interface Specification

Advanced Configuration and Power Interface Specification
19.3.2 ASL Literal Constants
This section describes how to encode integer and string constants using ASL.
19.3.2.1 Integers
DigitChar := ‘0’-‘9’
LeadDigitChar := ‘1’-‘9’
OctalDigitChar := ‘0’-‘7’
HexDigitChar := DigitChar | ‘A’-‘F’ | ‘a’-‘f’
Integer
DecimalConst
OctalConst
HexConst
ByteConst
WordConst
DWordConst
QWordConst
:= DecimalConst | OctalConst | HexConst
:= LeadDigitChar |
:= ‘0’ |
:= | |
:= Integer => 0x00-0xFF
:= Integer => 0x0000-0xFFFF
:= Integer => 0x00000000-0xFFFFFFFF
:= Integer => 0x0000000000000000-0xFFFFFFFFFFFFFFFF
Numeric constants can be specified in decimal, octal, or hexadecimal. Octal constants are preceded
by a leading zero (0), and hexadecimal constants are preceded by a leading zero and either a lower or
upper case ‘x’. In some cases, the grammar specifies that the number must evaluate to an integer
within a limited range, such as 0x00–0xFF, and so on.
19.3.2.2 Strings
String := ‘”’ Utf8CharList ‘”’
Utf8CharList := Nothing | |
Utf8Char := 0x01-0x21 |
0x23-0x5B |
0x5D-0x7F |
0xC2-0xDF 0x80-0xBF |
0xE0 0xA0-0xBF 0x80-0xBF |
0xE1-0xEC 0x80-0xBF 0x80-0xBF |
0xED 0x80-0x9F 0x80-0xBF |
0xEE-0xEF 0x80-0xBF 0x80-0xBF |
0xF0 0x90-0xBF 0x80-0xBF 0x80-0xBF |
0xF1-0xF3 0x80-0xBF 0x80-0xBF 0x80-0xBF |
0xF4 0x80-0x8F 0x80-0xBF 0x80-0xBF
EscapeSeq := SimpleEscapeSeq | OctalEscapeSeq | HexEscapeSeq
SimpleEscapeSeq := \' | \" | \a | \b | \f | \n | \r | \t | \v | \\
OctalEscapeSeq := \ OctalDigitChar |
\ OctalDigitChar OctalDigitChar |
\ OctalDigitChar OctalDigitChar OctalDigitChar
HexEscapeSeq := \x HexDigitChar |
\x HexDigitChar HexDigitChar
NullChar
:= 0x00
String literals consist of zero or more ASCII characters surrounded by double quotation marks ("). A
string literal represents a sequence of characters that, taken together, form a null-terminated string.
After all adjacent strings in the constant have been concatenated, a null character is appended.
Strings in the source file may be encoded using the UTF-8 encoding scheme as defined in the
Unicode 4.0 specification. UTF-8 is a byte-oriented encoding scheme, where some characters take a
single byte and others take multiple bytes. The ASCII character values 0x01-0x7F take up exactly
one byte.
786 April, 2015 Version 6.0