82801BA Datasheet, PDF (400/498 Pages) Intel Corporation – Intel 82801BA I/O Controller Hub 2 (ICH2) and Intel 82801BAM I/O Controller Hub 2 Mobile

AC’97 Audio Controller Registers (D31:F5)
13.1.12
SVID—Subsystem Vendor ID Register (Audio—D31:F5)
Address Offset:
Default Value:
Lockable:
2Dh–2Ch
0000h
No
Attribute:
Size:
Power Well:
Read/Write-Once
16 bits
Core
The SVID register, in combination with the Subsystem ID register, enable the operating
environment to distinguish one audio subsystem from the other(s). This register is implemented as
write-once register. Once a value is written to it, the value can be read back. Any subsequent writes
will have no effect.
Bit
Description
15:0 Subsystem Vendor ID Value—R/Write-Once.
13.1.13
SID—Subsystem ID Register (Audio—D31:F5)
Address Offset:
Default Value:
Lockable:
2Fh–2Eh
0000h
No
Attribute:
Size:
Power Well:
Read/Write-Once
16 bits
Core
The SID register, in combination with the Subsystem Vendor ID register make it possible for the
operating environment to distinguish one audio subsystem from the other(s). This register is
implemented as write-once register. Once a value is written to it, the value can be read back. Any
subsequent writes will have no effect.
Bit
15:0 Subsystem ID Value—R/Write-Once.
Description
13.1.14
INTR_LN—Interrupt Line Register (Audio—D31:F5)
Address Offset: 3Ch
Default Value: 00h
Lockable:
No
Attribute:
Size:
Power Well:
R/W
8 bits
Core
This register indicates which PCI interrupt line is used for the AC’97 module interrupt.
Bit
Description
7:0
Interrupt Line—R/W. This data is not used by the ICH2. It is used to communicate to software the
interrupt line that the interrupt pin is connected to.
13-6
82801BA ICH2 and 82801BAM ICH2-M Datasheet